Rozprawy doktorskie: „Morphotectonics”

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Riley, C. D. B. "The morphotectonics of the Spanish Sierra Nevada". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294782.

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Gilchrist, Alan Robert. "Morphotectonics of passive continental margins : application to south-western Africa". Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316915.

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Scott, James Morfey, i n/a. "Tectonic evolution of the Eastern Fiordland Gondwana margin". University of Otago. Department of Geology, 2008. http://adt.otago.ac.nz./public/adt-NZDU20081003.094325.

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Eastern Fiordland is an eroded Carboniferous to Cretaceous arc assemblage juxtaposed against the Western Fiordland Gondwana continental margin along the Grebe Shear Zone. In the Manapouri region, Eastern Fiordland is composed of scattered metasedimentary and plutonic rocks of Carboniferous, Jurassic and Jurassic-Early Cretaceous age. Quantitative P-T estimates on rare paragneiss assemblages, coupled with LA-ICP-MS analyses of metamorphic overgrowths on detrital zircon grains, demonstrate metamorphism at low to middle amphibolite facies (<6 kbar, c. 600�C) at 145.0 � 2.8 Ma (all quoted errors at 2[sigma]). The Manapouri-Lake Te Anau area of Eastern Fiordland also exposes scattered fragments of the Mesozoic volcano-sedimentary Loch Burn Formation. Relict sedimentary features within this long-lived Early Jurassic to Early Cretaceous unit indicate deposition in a mostly terrestrial or shallow water environment that was fed by debris flows from proximal granitic and volcanic topographic high points. Deposition of the Loch Burn Formation in the Murchison Mountains is bracketed between a 342.3 � 1.5 Ma basal granite and an intrusive 157.6 � 1.4 Ma quartz diorite. Metamorphism throughout the unit achieved greenschist and amphibolite facies temperatures (P unconstrained) in the Early Cretaceous (post c. 148 Ma and prior to c. 121 Ma). Although metasedimentary rocks provide insights into the tectonic evolution of Eastern Fiordland, a range of compositionally heterogeneous plutonic rocks dominates the geology. At Lake Manapouri, these comprise four principal associations: (1) the composite Pomona Island Granite (Carboniferous-Permian and Jurassic), (2) the Beehive Diorite (148.6 � 2.3 Ma), (3) the heterogeneous Hunter Intrusives (Carboniferous, Jurassic and Early Cretaceous) of the Darran/Median Suite and (4) HiSY granitoid dikes of the Separation Point Suite (123.5 � l.2Ma). The latter suite also occurs in immediately adjacent parts of Western Fiordland, forming the Refrigerator Orthogneiss (120.7 �1.1 Ma), the Puteketeke Granite (120.9 � 0.8 Ma) and the West Arm Leucogranite (116.3 � 1.2 Ma). Geobarometry indicates the Jurassic portions of the Darran/Median Suite were emplaced between 4 - 6 kbar and Western Fiordland Early Cretaceous Separation Point Suite between 5 - 7 kbar. Zircon initial �⁷⁷Hf/�⁷⁶Hf isotopic ratios suggest that Separation Point Suite magma could be derived from the same Paleozoic - Late Neoproterozoic mantle source as the Jurassic portion of the Hunter Intrusives member of the Darran/Median Suite. However, Early Cretaceous plutons west of the Early Cretaceous active margin (and study area) have significantly more evolved source regions, reflecting the influence of continental Gondwana on lithosphere composition. Initial �⁷⁷Hf/�⁷⁶Hf ratios from the Loch Burn Formation Carboniferous basal granite zircon are slightly less primitive than either Darran/Median or Separation Point Suite but nowhere near as evolved as similar-aged zircon in the Eastern Fiordland Mt Crescent Paragneiss unit in the Hunter Mountains. The Cambrian/Early Ordovician Russet Paragneiss, which lies just west of the Grebe Mylonite Zone in Western Fiordland and has been intruded by a range of Early Paleozoic to Mesozoic plutons, was metamorphosed at 7.5 � 1.2 kbar, 633 � 25�C at 348.6 � 12 Ma and exhibits no evidence for Jurassic re-equilibration. Zircon U-Pb isotopes from a pelitic schist enclave within the Western Fiordland Mt Murrell Amphibolite are interpreted to show that these and associated intrusive rocks were also metamorphosed at kyanite-grade in the Carboniferous. This event, �M1�, generated a pervasive lineation and distinctive pargasite-anorthite-kyanite/corundum-bearing assemblages in layered aluminous components to the Mt Murrell Amphibolite, garnet-amphibole-biotite-kyanite-gedrite-plagioclase-quartz in metasomatised tonalite at the Mt Murrell Amphibolite margins, and low CaO-garnet in pelitic schist enclaves within the amphibolite. P-T estimates suggest M1 took place at 6.6 � 0.8 kbar, 618 � 25�C. Both the timing and P-T conditions of M1 overlap with metamorphism of the Russet Paragneiss. However, the layered amphibolites and pelitic schist enclaves partially re-equilibrated in the Early Cretaceous (c. 115 Ma) at higher pressure (8.8 � 0.9 kbar). This event, �M2�, generated static assemblages of margarite, epidote, chlorite, oligoclase-andesine and second-generation kyanite in the layered amphibolites and relict olivine gabbronorite, and high-CaO garnet rims, biotite, plagioclase, quartz, kyanite and staurolite in the pelitic schist enclaves. Trace element chemistries of c. 340 Ma zircon grains in the schist have unusual smoothed Ce/Ce* anomalies and high Th/U ratios. These properties may be result of fluid flow and metasomatism from the enveloping amphibolite during imposition of the penetrative M1 lineation. Early Cretaceous (c. 115 Ma) zircon overgrowths and chemistries (low heavy rare earth elements, low Th/U ratios, large Eu/Eu* anomalies) are compatible with formation in the presence of local M2 garnet and plagioclase. M2 was coeval with amphibolite to garnet-granulite facies metamorphism of the regionally extensive Western Fiordland Orthogneiss and Arthur River Complex, thus demonstrating that high-pressure metamorphism was not restricted to the Western Fiordland Early Cretaceous components and their marginal metasedimentary rocks. The Grebe Mylonite Zone forms a lithologic, metamorphic, isotopic and structural boundary between Eastern and Western Fiordland. This 200 to 300 metre-wide and > 50 km long north-striking mylonitic zone is the prominent manifestation of deformation associated with the wider (c. 30 km) Grebe Shear Zone, which extends into Eastern and Western Fiordland. Qualitative and quantitative P-T estimates indicate the currently exposed level of the Grebe Mylonite Zone was active at amphibolite facies conditions (c. 600�C and c. 6 kbar). Coupled U-Pb and Ar-Ar data indicate the mylonite zone was active at, or between, c. 128 and 116 Ma. Temperature-time profiles constructed along a transect perpendicular to the shear zone, used in conjunction with fabric data and the orientation of nearby Tertiary unconformities, suggest that the currently sub-vertical shear zone was rotated during the Cenozoic from an initially steeply east-dipping geometry with a reverse sense of shear. This style of deformation is consistent with an inclined continuously partitioned transpressional structure. Synkinematic emplacement and deformation of the Refrigerator Orthogneiss implies that Grebe Shear Zone provided a crustal anisotropy that facilitated the movement and emplacement of some Separation Point Suite magmas through the crust. Data collected here are interpreted to show that the Grebe Shear Zone is a terrane-bounding suture. Differences in metasedimentary rock composition, age, provenance and metamorphism across the zone suggest that the crustal framework to Eastern Fiordland did not forth in its current tectonic position. Instead, the Mesozoic portion of Eastern Fiordland is inferred to have developed allochthonously with respect to Western Fiordland, with components internally dismembered and rearranged during Jurassic metamorphism and juxtaposition in the Early Cretaceous. However, the Jurassic portion of the arc may have developed near the Gondwana margin because the Jurassic Borland Paragneiss contains detritus that can be partly matched to sources in the Western and Eastern Provinces of New Zealand, as well as early parts of the Darran/Median Suite and Loch Burn Formation. Recognition that the Eastern Fiordland arc was faulted against and then over Western Fiordland in the Early Cretaceous provides a possible driving mechanism for coeval transpressive shortening, rapid burial and high-pressure metamorphism (e.g., as seen in the Mt Murrell Amphibolite) of the lower Western Fiordland crust.

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Mathew, Manoj joseph. "Geomorphology and Morphotectonic Analysis of north Borneo". Thesis, Lorient, 2016. http://www.theses.fr/2016LORIS408/document.

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L’analyse géomorphologique d'une zone d’étude permet d’identifier et de comprendre le rôle des facteurs de contrôle tectonique et climatique sur l’évolution passée, récente et future de la surface topographique. Ce travail de recherche porte sur l’analyse géomorphologique des paysages du secteur de l’état de Sarawak, localisé au nord de l’île de Bornéo en contexte tropical. À travers l'analyse morphotectonique des deux plus grands bassins versants : le bassin versant du Rajang et du Baram, il a été possible de dresser une première évaluation du cadre morpho-tectonique de la région et des conséquences topographiques. Les bassins versants étudiés et situés au centre et au Nord de Sarawak drainent une superficie totale d'environ 75 000 km². L'île de Bornéo présente une couverture végétale dense spécifique aux régions tropicales, et demeurant souvent difficile d’accès. Cette île témoigne de terrains montagneux et accidentés, découpés par de vallées profondes aux flancs abruptes, entraînant des taux de dénudation notables depuis le Miocène. La première contribution est d’identifier les principales failles mineures et majeures ayant par réactivation participées au rajeunissement de la surface topographie à l’échelle régionale. À l’échelle des deux bassins versants, les facteurs géomorphologiques suivants comme l’intégrale hypsométrique, les facteurs d’asymétrie, les anomalies de pente identifiées le long des rivières ont été cartographiées à l’aide des techniques d'autocorrélation spatiale. Les principaux mouvements verticaux identifiés sont accommodés le long des accidents structuraux majeurs et des chevauchements spécifiques de la zone Nord de Bornéo. Parmi les autres résultats, il est également observé des surfaces planes reliques, à haute altitude, n’ayant pas encore réajustées leur surface d’équilibre depuis les 5 derniers Ma malgré de phases rapides de soulèvement connues. Enfin, à l’échelle de la zone d’étude, où les contrastes lithologiques sont absents, la présence de nombreuses ruptures de pente ou knickpoints sont observés le long des principaux profils longitudinaux des rivières. Les ruptures de pente fortes sont dans la majorité corrélables aux principaux accidents structuraux. Des observations de terrain viennent renforcer nos hypothèses par la présence de terrasses fluviatiles soulevées. Ce travail d’analyse d’indices géomorphologiques complétés par des observations de terrain permet alors de proposer un modèle synthétique des principaux facteurs de contrôle responsables du rajeunissement de la surface topographique de l’état de Sarawak jusqu’alors sous-estimé et méconnu
Geomorphic assessment of a region is considered to be crucial in understanding the present day landscapeand forces that have acted and is currently acting on the ever evolving topography. This thesis explores the geomorphology of the tropical landscape of Sarawak, north Borneo through morphotectonic analysis of two of the largest drainage basins of the entire Borneo Island: the Rajang and Baram basin; making this work the first systematic tectono-geomorphic evaluation of the region. The island of Borneo is enveloped by thick rainforests, hostile rugged mountainous terrain with deep and steep valleys, and is characterized by high denudation rates since Miocene. The studied drainage basins flow across entire central and north Sarawak and drain a total combined area of ca. 75, 000 km². The first contribution to the field is by conducting a study on the presence of active tectonic forces that modify the topography through rejuvenation of major and minor faults. The analysis using basin-scale hypsometry, asymmetry factor, normalized channel steepness index and spatial autocorrelation techniques showed that the landscape has been rejuvenated and experiences tectonic deformation to present-day in the form of active folding of the fold-thrust orogenic belts of the Interior Highlands which form the backbone of Borneo. From the results, we highlighted the presence of relict surfaces of landscapes which were isolated at high elevations unable to balance a rapid uplift phase experienced after 5 Ma. We extended the study in order to identify the current stage of landscape development by conducting stream profile analysis which displayed an array of knick-zones and knick points devoid of lithological and climatic controls. Deep V-shaped valleys formed in the zones that demonstrated active folding of the highlands also revealed relief anomalies highlighted through topographic analysis. We showed that enhanced orographic precipitation following the rapid creation of relief has supported adjustment of the topography to a state of transience. In the next part of this work, we conducted swath profile analysis, minimum bulk erosion and channel steepness anomaly maps in order to identify the role of rapid incision in exacerbating erosion rates as a response to tectonic and climatic forcing. We show that there exists a coupling between incision rates, precipitation and channel steepness which shows a relation of direct proportionality. Extensive geomorphic and sedimentological field campaigns were carried out in order to substantiate our results and conclusions. The field work revealed the presence of uplifted fluvial terraces, waterfalls and cataracts corresponding to knick-points identified by us. Finally, we combine our results from the geomorphic analysis and stratigraphic field work in order to construct a conceptual model showing the geomorphic evolution of Sarawak, north Borneo

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Ghosal, Dibakar. "Shallow subsurface morphotectonics of the offshore Northern Sumatra Subduction system using high resolution marine Geophysical datasets". Paris, Institut de physique du globe, 2013. http://www.theses.fr/2013GLOB0007.

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Bream, Brendan R. "Tectonic implications of para- and orthogneiss geochronology and geochemistry from the southern Appalachian crystalline core". VIEW WEB VERSION, 2003. http://etd.utk.edu/2003/BreamBrendan.pdf.

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Thesis (Ph. D.)--University of Tennessee, Knoxville, 2003.
Title from title page screen (viewed Nov. 11, 2003). Thesis advisor: Robert D. Hatcher. Document formatted into pages (xiii, 296 p. : col. ill., col. maps). Vita. Includes bibliographical references.

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Müller, Stefan G. "The tectonic evolution and volcanism of the Lower Wyloo Group, Ashburton Province, with timing implications for giant iron-ore deposits of the Hamersley Province, Western Australia /". Connect to this title, 2005. http://theses.library.uwa.edu.au/adt-WU2006.0043.

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Paquet, Fabien. "Evolution morphostructurale des bassins de marge active en subduction : l'exemple du bassin avant arc de Hawke Bay en Nouvelle-Zélande = Morphostructural evolution of active subduction margin basins : the example of the Hawke Bay forearc basin, New Zealand /". Rennes : CNRS, Université de Rennes, 2008. http://library.canterbury.ac.nz/etd/adt-NZCU20080225.224857.

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Thesis (Ph. D.) -- l'Université de Rennes, 2007.
"Thése de Doctorat de l'Université de Rennes 1 réalisée en co-tutelle avec l'Université de Canterbury (Christchurch, Nouvelle-Zélande)." "Soutenue le 9 novembre 2007." Includes bibliographical references. Also available via WWW.

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Garlick, Sarah R. "Granulite- to amphibolite-facies metamorphism and penetrative deformation in a disrupted ophiolite, Kangaroo Mountain area, Klamath Mountains, California a deep view into the basement of an accreted, oceanic island arc /". Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1317326781&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Janoni, Clayton Ricardo [UNESP]. "Compartimentação morfotectônica da Alta Mogiana Paulista (Nordeste do Estado de São Paulo)". Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/92865.

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Made available in DSpace on 2014-06-11T19:26:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-08Bitstream added on 2014-06-13T19:47:07Z : No. of bitstreams: 1 janoni_cr_me_rcla.pdf: 8114045 bytes, checksum: da84b4905898a99750a0388f28b8ee26 (MD5)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
A atividade neotectônica no globo terrestre é responsável por importantes processos geológicos recentes controlando a evolução de paisagens, associada à reativação episódica de zonas de fraqueza crustal, responsáveis diretas por estes processos, marcando os principais sítios de deformação. Os estudos morfotectônicos inseridos na temática neotectônica subsidiam importantes investigações aplicadas à Geomorfologia e contribuem para o entendimento da evolução do relevo e da implantação de bacias de drenagem controladas pelas formas e estruturas. A Alta Mogiana Paulista (Altinópolis/Batatais/Serrana) corresponde à região nordeste do estado de São Paulo, é alvo de estudos geológicos e geomorfológicos direcionados para o contexto da evolução paisagem local. No contexto geológico a região esta inserida em domínios da Bacia do Paraná, com litologias dominantes do Mesozóico e do Cenozóico. A área apresenta uma estrutura simples, na forma de um grande monoclinal com mergulho para NW, afetado por falhas normais e transcorrentes, responsáveis pelo arranjo da drenagem e das formas de relevo. O padrão de fraturamento das rochas da Alta Mogiana Paulista apresentam um predomínio de lineamentos com direção N-S e E-W e, com menor importância, nas direções NE e NW. As principais unidades geomorfológicas mapeadas foram: colinas amplas e médias, escarpas, serras alongadas e morros testemunhos inseridos na província das Cuestas Basálticas. No quadro morfotectônico, os principais fatores que ilustram esta compartimentação estão impressos no rearranjo da drenagem na forma de capturas e anomalias na porção central da área de estudo, com direções NE para os alinhamentos destas feições. As coberturas sedimentares superficiais recobrem toda área de estudo, com maiores concentrações...
The neotectonic activity in the globe is responsible for important recent geologic processes controlling the landscapes evolution associated to episodic reactivation of zones of crustal weakness. Those structures make strong control for the processes, marking the major sites of strain concentration. The morphotectonic studies inserted in the thematic of Neotectonics subsidize important inquiries applied to the Geomorphology and contribute to the understanding of the relief evolution and the implantation of the drainage basins controlled by geological bodies and structures. The Alta Mogiana Paulista region (Altinópolis/Batatais/Serrana) in the northeastern of São Paulo State was the target of geologic and geomorphologic studies directed to the local landscape evolution context. In the geologic context the region is inserted into the Paraná Basin domains exhibiting lithologies from Mesozoic and Cenozoic times. The studied area shows a simple structure of a great monocline dipping towards NW affected by normal and transcurrent faults responsible by the framework of the drainage and relief forms. In the Alta Mogiana Paulista rock fractures pattern predominate lineaments directed N-S and E-W and the NE and NW are less important. The principal geomorphologic mapped units were ample and middle hills, scarps, elongated ranges and residual hills inserted into the Basaltic Cuestas Province. In the geomorphologic picture the principal factors that illustrate this compartmentation are printed in the rearrangement of the drainage elements forming river captures and anomalies in the central portion of the studied area aligned along the NE direction. The surface sedimentary covers are recognized along all the area most concentrated in the high planes and covering the hills level into the depressed areas. The geologic and geomorphologic evolution... (Complete abstract, click electronic access below)

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Pavano, Francesco. "Riconoscimento, caratterizzazione cinematica e valutazione dei tassi di deformazione di strutture tettoniche tardo quaternarie lungo il confine meridionale dell Arco Calabro". Doctoral thesis, Università di Catania, 2014. http://hdl.handle.net/10761/1567.

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Nello studio dell evoluzione tettonica recente dell arco Calabro-Peloritano si è fatto fin qui riferimento ad una enorme mole di dati geologici, non estendibili oltre circa 600 ka, cui si sono aggiunti i dati dei terrazzi marini che hanno coperto l intervallo temporale mancante, lasciando ampie aree distanti dalla costa prive di informazioni. Negli ultimi decenni, i dati geodetici hanno fornito informazioni utilissime per la ricostruzione della cinematica attiva, riferendosi comunque ad una finestra temporale troppo ristretta, che non garantisce affatto la trasferibilità del dato sul lungo periodo. Lo studio è consistito in una analisi del paesaggio della Sicilia nord-orientale, condotta in due parti. La prima ha previsto l analisi del rilievo, al fine di ottenere le informazioni regionali utili all identificazione del quadro deformativo recente, da confrontare con i dati geologici disponibili. La seconda parte è invece consistita in una analisi morfometrica quantitativa del reticolo idrografico, effettuata con lo scopo di evidenziare la significatività dei diversi indici generalmente utilizzati in letteratura per studi sulla tettonica recente e attiva e selezionare i campi di applicazione ottimale per ognuno di essi. L analisi del rilievo ha delineato la presenza di un blocco crostale denominato Blocco Mobile Peloritano (BMP), indipendente dai movimenti delle aree adiacenti. I margini del blocco corrispondono a strutture già conosciute in letteratura, lungo le quali si realizzano chiare discontinuità di comportamento dell evoluzione a lungo periodo del paesaggio. Le discontinuità morfologiche e tettoniche individuate coincidono con nette variazioni delle anomalie gravimetriche, che attesterebbero il loro radicamento profondo. Lungo il limite occidentale del BMP è stato possibile misurare una velocità relativa, rispetto al resto della Sicilia, di circa 1 mm/a, secondo un vettore orientato NE ed inclinato di circa 16° verso SW. In settori discreti del blocco mobile, faglie normali, orientate perpendicolarmente alla direzione di movimento del blocco, si sono generate per locali fenomeni di tettonica di collasso, mostrando parametri geometrici che denunciano un loro rilevante potenziale sismogenico, in linea con le stime di intensità degli eventi sismici di epoca storica. L individuazione del BMP ha sancito l instaurarsi di una nuova dinamica responsabile della frammentazione della terminazione meridionale dell arco. Il quadro tettonico ricostruito è stato utilizzato come riferimento indispensabile per l interpretazione dei risultati delle analisi morfometriche, discusse nella seconda parte. Per il riconoscimento dei limiti del BMP e l individuazione dei due domini al suo interno sono risultate significative le anomalie gerarchiche e la densità di drenaggio, perfettamente sovrapponibili ai risultati ottenuti nella prima parte. La metodologia adottata ha permesso di verificare l efficacia dell utilizzo come elemento di calcolo solo degli indici relativi ai bacini di un determinato ordine, preliminarmente scelto come ordine gerarchico significativo, che snellisce di molto le procedure senza intaccare la affidabilità dei dati ottenuti. Le analisi hanno evidenziato che la significatività sia del fattore di asimmetria come tiltmetro naturale che degli SL index, nonostante essi siano tra gli indici più diffusi in analisi delle deformazioni attive, risulta molto ridimensionata e che l uso di questi indici andrebbe ristretta ai casi in cui la deformazione tettonica sia stata documentata anche da dati indipendenti di altra natura. Nel corso della ricerca è stata, infine, applicata una metodologia di indagine dei profili longitudinali dei corsi d acqua da abbinare allo studio dei terrazzi marini, allo scopo di ampliare l estensione delle fasce analizzate.

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Schwaiger, Hans Frederick. "An implementation of smoothed particle hydrodynamics for large deformation, history dependent geomaterials with applications to tectonic deformation /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/6807.

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Fajardo, Atiria. "Neotectonic evolution of the Serrania Del Interior range and Monagas fold and thrust belt, Eastern Venezuela : Morphotectonics, Seismic Profiles Analyses and Paleomagnetism". Thesis, Pau, 2015. http://www.theses.fr/2015PAUU3031/document.

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La convergence oblique entre les plaques Caraïbes et Amérique du Sud à partir de l'Oligocène a conduit à la formation de la cordillère « Serranía del Interior » (SDI) et de son avant pays au sud (bassin de Maturín) et la ceinture plissée de Monagas. D’abord transpressif (direction NW-SE), le déplacement entre les deux plaques devient à compter de ~12 Ma principalement une translation O-E qui s’accommode principalement sur la faille d’El Pilar. Cependant, des indices de compression active ont été identifiés à la terminaison de la faille d'Urica dans la chaine plissée de Monagas. Pour discuter des mécanismes de cette déformation compressive actuelle, nous avons mis en œuvre une interprétation sismique (2D et 3D), une étude géomorphologique et une étude paléomagnétique. Depuis le front sud de la SDI dans la chaîne plissée de Monagas, l'interprétation sismique et l’analyse géomorphologique se sont concentrées sur les chevauchements de San Félix, Tarragona, Punta de Mata, Jusepín et Amarilis. Deux discordances miocènes (Mid-Miocene Unconformity (MMU) de ~10 Ma et Late Miocene Unconformity (LMU) de ~5,3 Ma) ont été cartographiées sur la sismique. En s’appuyant sur la LMU, il a été calculé à l’aplomb de ces accidents un taux de soulèvement plio-pléistocène de ~0,4 mm/a. Invisibles sur la sismique, des déformations ont aussi été observées en surface sur ces accidents (des terrasses fluviatiles basculées, plissées et faillées et des anomalies de drainage). Datées par des méthodes cosmonucléides (10Be et 26Al), l’âge des terrasses alluviales déformées sont compris entre ~90 ka sur le chevauchement de Tarragona et ~15 ka dans la zone de Punta de Mata. Un taux minimal de soulèvement pléistocène terminal à l’aplomb des chevauchements a été calculé entre 0,1 et 0,6 mm/a. Cette gamme de vitesse recouvre celle renvoyée par la LMU et montre que la déformation n'a pas varié significativement pendant les derniers 5,3 Ma. Ces observations montrent que les chevauchements de Tarragona, Pirital El Furrial et d’autres plus jeunes développés dans la formation Carapita restent actifs. Cette déformation superficielle s’estompe rapidement vers l’est près de la ville Maturín. Nous interprétons cette déformation comme liée au jeu récent de la faille d'Urica qui se termine au sud en queue de cheval. La faille d’Urica accommoderait donc une partie du déplacement entre plaques Caraïbe et Amérique du Sud. Une étude paléomagnétique a été réalisée dans les blocs de Caripe et Bergatín au sein de la SDI où 27 localités ont été échantillonnées dans les sédiments du Crétacé au Paléocène. Une observation clé de cette étude a été la mise en évidence d'une composante paléomagnétique stable déviée vers le Nord Est avec des polarités normale et inverse. Les analyses statistiques de ces composantes indiquent une acquisition postérieure au plissement de la SDI (< ~12 Ma). La déclinaison moyenne dans les blocs de Caripe et de Bergatín indique une rotation horaire de R=37º±4 º autour d’un axe vertical. Le taux de rotation post-Miocene moyen avoisine ~3.7º/Ma et reste probablement actif. Nous proposons de rattacher cette rotation horaire à un système de failles type "Riedel" (Urica et San Francisco) en relation avec la faille d’El Pilar
In Northeastern Venezuela, the tectonic provinces of the Serranía Del Interior thrust belt (high hills), the Monagas Thrust belt (foothills) and the Maturín foreland basin formed as a result of the oblique convergence between the Caribbean and South American plates since the Oligocene. GPS data show that post 12 My wrenching component between the plates is accommodated predominantly by the E-W strike-slip El Pilar Fault. However, evidence of active compression has been identified in the southern limit of the NW-SE dextral Urica Fault, specifically, in the Monagas Fold and Thrust Belt. In order to constrain the neotectonics of this area, this thesis presents a combined approach, which includes geomorphological study, seismic and paleomagnetism. In the Monagas Fold and Thrust Belt, the geomorphological study and the seismic interpretation were focused on five zones. From the foothills to the deformation front, these zones are: San Felix, Tarragona, Punta de Mata, Jusepín and Amarilis. These areas show surface deformations such as topographic uplifts, tilted terraces, folded terraces, faulted terraces, and drainage anomalies. The dating of the river terraces through 10Be and 26Al methods indicates that these terraces formed in the Late Pleistocene. The oldest terrace located in the Tarragona zone has a maximum exposure age of ~90 ky and the youngest located in the Punta de Mata zone of ~15 ky. From this dating, a minimum vertical deformation rate between ~0.6-0.1 mm/y was calculated for this area. Using the seismic interpretation of a 3D block, the surfaces of two unconformities (MMU and LMU) have been mapped. The age obtained for the LMU (~5.3 My), yield a Plio-Pleistocene uplift rate between ~0.3-0.4 mm/y, which is close to the vertical deformation rate calculated from the terraces dated. These similar rates seem to indicate that the deformation rate in the MFTB has not changed significantly for the last 5.3 My. The deformed surfaces observed in the field and in DEM images coincide vertically with the deep structures interpreted in the seismic lines. I propose that the deformation on the surface is linked to the Tarragona, Pirital, Furrial thrusts and the Amarilis Backthrust activity and to the youngest thrusts developed in the Carapita Formation. However, this surface deformation dies out near the city of Maturín, therefore, the neotectonic deformation is inferred to be caused by local tectonics. I propose that this local compressive deformation could have been generated by a horsetail termination in the southern limit of the Urica Fault which reactivated the oldest thrusts (Tarragona and Pirital thrusts) and deformed the post-Middle Miocene units until reaching the surface. In the zones where the El Pilar Fault mainly accommodates the wrenching component, block rotation is likely. For that reason, a paleomagnetic study was conducted in the Caripe and Bergatín blocks of the Serranía Del Interior where 27 sites were sampled in Cretaceous to Paleocene sediments. Statistics analyses of the components yield a negative bedding-tilt test, indicating that this component was acquired post ~12 My after the folding process in the Serranía del interior. The average declination indicates a clockwise block rotation of R = 37º ± 4º and a post-Middle Miocene rotation rate of ~3.7º/My in both the Caripe and Bergatín blocks. This rotation rate is probably still active. I propose to relate the regional clockwise rotation to the development of a synthetic Riedel shear system formed by the El Pilar Fault (master regional fault) and by the Urica and San Francisco synthetic Riedel shears

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Janoni, Clayton Ricardo. "Compartimentação morfotectônica da Alta Mogiana Paulista (Nordeste do Estado de São Paulo) /". Rio Claro : [s.n.], 2007. http://hdl.handle.net/11449/92865.

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Orientador: Norberto Morales
Banca: Jairo Roberto Jimenez Rueda
Banca: Mirna Aparecida Neves
Resumo: A atividade neotectônica no globo terrestre é responsável por importantes processos geológicos recentes controlando a evolução de paisagens, associada à reativação episódica de zonas de fraqueza crustal, responsáveis diretas por estes processos, marcando os principais sítios de deformação. Os estudos morfotectônicos inseridos na temática neotectônica subsidiam importantes investigações aplicadas à Geomorfologia e contribuem para o entendimento da evolução do relevo e da implantação de bacias de drenagem controladas pelas formas e estruturas. A Alta Mogiana Paulista (Altinópolis/Batatais/Serrana) corresponde à região nordeste do estado de São Paulo, é alvo de estudos geológicos e geomorfológicos direcionados para o contexto da evolução paisagem local. No contexto geológico a região esta inserida em domínios da Bacia do Paraná, com litologias dominantes do Mesozóico e do Cenozóico. A área apresenta uma estrutura simples, na forma de um grande monoclinal com mergulho para NW, afetado por falhas normais e transcorrentes, responsáveis pelo arranjo da drenagem e das formas de relevo. O padrão de fraturamento das rochas da Alta Mogiana Paulista apresentam um predomínio de lineamentos com direção N-S e E-W e, com menor importância, nas direções NE e NW. As principais unidades geomorfológicas mapeadas foram: colinas amplas e médias, escarpas, serras alongadas e morros testemunhos inseridos na província das Cuestas Basálticas. No quadro morfotectônico, os principais fatores que ilustram esta compartimentação estão impressos no rearranjo da drenagem na forma de capturas e anomalias na porção central da área de estudo, com direções NE para os alinhamentos destas feições. As coberturas sedimentares superficiais recobrem toda área de estudo, com maiores concentrações... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The neotectonic activity in the globe is responsible for important recent geologic processes controlling the landscapes evolution associated to episodic reactivation of zones of crustal weakness. Those structures make strong control for the processes, marking the major sites of strain concentration. The morphotectonic studies inserted in the thematic of Neotectonics subsidize important inquiries applied to the Geomorphology and contribute to the understanding of the relief evolution and the implantation of the drainage basins controlled by geological bodies and structures. The Alta Mogiana Paulista region (Altinópolis/Batatais/Serrana) in the northeastern of São Paulo State was the target of geologic and geomorphologic studies directed to the local landscape evolution context. In the geologic context the region is inserted into the Paraná Basin domains exhibiting lithologies from Mesozoic and Cenozoic times. The studied area shows a simple structure of a great monocline dipping towards NW affected by normal and transcurrent faults responsible by the framework of the drainage and relief forms. In the Alta Mogiana Paulista rock fractures pattern predominate lineaments directed N-S and E-W and the NE and NW are less important. The principal geomorphologic mapped units were ample and middle hills, scarps, elongated ranges and residual hills inserted into the Basaltic Cuestas Province. In the geomorphologic picture the principal factors that illustrate this compartmentation are printed in the rearrangement of the drainage elements forming river captures and anomalies in the central portion of the studied area aligned along the NE direction. The surface sedimentary covers are recognized along all the area most concentrated in the high planes and covering the hills level into the depressed areas. The geologic and geomorphologic evolution... (Complete abstract, click electronic access below)
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Schellart, Wouter Pieter. "Subduction rollback, arc formation and back-arc extension". Monash University, School of Geosciences, 2003. http://arrow.monash.edu.au/hdl/1959.1/9485.

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May, Bryce Derrick. "Comparative geomorphology of two active tectonic structures, near Oxford, North Canterbury". Thesis, University of Canterbury. Geological Sciences, 2004. http://hdl.handle.net/10092/1521.

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The North Canterbury tectonic setting involves the southward propagating margin of easterly strike-slip activity intersecting earlier thrust activity propagating east from the Alpine Fault. The resulting tectonics contain a variety of structures caused by the way these patterns overlap, creating complexities on the regional and individual feature scale. An unpublished map by Jongens et al. (1999) shows the Ashley-Loburn Fault System crossing the plains from the east connected with the Springfield Thrust Fault in the western margins, possibly the southern limit of the east-west trending strikeslip activity. Of note are two hill structures inferred to be affected by this fault system. View Hill to the west, is on the south side of this fault junction, and Starvation Hill further east, was shown lying on the north side of a left stepover restraining bend. During thrust uplift and simple tilting of the View Hill structure, at least two uplift events post date last Pleistocene aggradation accounting for variations in scarp morphology. Broad constraints on fault dip and the age of the displacement surface suggest that slip-rates are in the order of 0.5 mm/year. East from View Hill, the strike-slip fault was originally thought to curve northeast, around the southeast of Starvation Hill. But there is neither evidence of a scarp, nor other clear evidence of surface faulting at Starvation Hill, which poses the question of the extent to which folding may reflect both fault geometry and fault activity. Starvation Hill is a triangular shape, with a series of distinctive smooth, semi-planar surfaces, lapping across both sides of the hill at a range of elevations and gradients. These surfaces are thought to be remnants of old river channels, and are indicative of tilting and upwarping of the hill structure. 3D computer modelling of these surfaces, combined with studies of the cover sequence on the hill, resulted in inferences being drawn as to the location of hinge lines of a dual-hinged anticline and an overview of the tectonic history of the hill. This illustrates the potential to apply topographical and geomorphic studies to the evolution of geometrically complex structures Starvation Hill is interpreted to be the result of two fault-generated folds, one fault trending north, the other, more recent fault, trending east. These two faults are thought to be sequentially developed segments of the original fault zone inferred by Jongens et al. (1999) but with reinterpreted location and mechanism detail. The presence of two faults has resulted in overprinted differential uplift of the structure, which has been significantly degraded, especially in the southwest corner of the hill. The majority of the formation of the northerly trending structure of Starvation Hill is inferred to be pre-Otiran, with uplift of the later east trending structure continuing into the late Pleistocene and Holocene.

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Cortes, João Paulo Soares de. "Controle estrutural e classificação do canal no baixo Tapajós : contribuições para a geomorfologia da Amazônia /". Rio Claro, 2020. http://hdl.handle.net/11449/192952.

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Orientador: George Luiz Luvizotto
Resumo: A formação das rias fluviais na Amazônia possui uma relação bem conhecida com o processo de avanço do nível do mar durante o Holoceno. Sugestões sobre a presença de controle estrutural e tectônico na gênese destas e de outros elementos do relevo amazônico tem sido levantadas por diversos autores, porém poucos elementos conclusivos foram apresentados até o momento. Este trabalho apresenta, no primeiro momento, uma série de evidências de diferentes fontes mostrando controle estrutural ao longo do ria do Tapajós e em áreas de terra firme adjacentes. A metodologia utilizada, é inovadora por integrar dados geomorfológicos, geológicos e geofísicos (sísmica, magnetometria e gravimetria) obtidos sem custo e disponíveis para grandes áreas, o que é uma grande vantagem em uma zona de difícil acesso como a Amazônia. Trata-se ainda de uma abordagem pouco usual dentro da geomorfologia na qual encontramos resultados muito promissores. Os resultados mostram a influência de elementos estruturais na configuração do relevo amazônico na região do baixo Tapajós. É proposto um modelo de horsts e grábens limitados por lineamentos com direção ENE-WSW com expressão regional. Em seguida apresentamos uma classificação para o canal do Tapajós baseado em variáveis morfométricas extraídas de perfil transversal. A classificação apresenta três trechos distintos para o canal do Tapajós no perímetro analisado, denominados Trecho do Canal Estreito, Baixo Trecho da Ria e Alto Trecho da Ria. Estes trechos possue... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The formation of the fluvial rias in the Amazon has a well-known relationship with the process of sea level transgression during the Holocene. Suggestions about the presence of structural and tectonic control in the genesis of these and other elements of the Amazonian relief have been raised by several authors, but few conclusive elements have been presented so far. This work presents, in the first moment, a series of evidences from different sources showing structural control along the Tapajós Ria and in adjacent land areas. The methodology used is innovative because it integrates geomorphological, geological and geophysical data (seismic, magnetometry and gravimetry) obtained at no cost and available for large areas, which is a great advantage in an area of difficult access such as the Amazon. It is also an unusual approach within geomorphology in which we find very promising results. The results show the influence of structural elements in the configuration of the Amazonian relief in the region of the lower Tapajós. A model of horsts and grabens limited by lineaments with regional expression is proposed. Next, we present a classification for the Tapajós channel based on morphometric variables extracted from transversal profiles. The classification presents three distinct sections for the Tapajós channel in the analyzed perimeter, here called Narrower Channel Reach, Lower Ria Reach and Higher Ria Reach. These reaches have statistical support and agreement with most of the s... (Complete abstract click electronic access below)
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Real, Sílvia. "Gráben Ribeirão das Lajes, RJ : evolução estrutural cenozoica e morfotectônica /". Rio Claro, 2019. http://hdl.handle.net/11449/190952.

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Orientador: George Luiz Luvizotto
Resumo: O Gráben Ribeirão das Lajes (GRL) foi mapeado no limite entre as escarpas da Serra do Mar e o Gráben da Guanabara, no estado do Rio de Janeiro, Brasil. O presente estudo buscou caracterizar a configuração e evolução tectônica cenozoica do GRL a partir de métodos que integram procedimentos em laboratório e trabalhos de campo, envolvendo Geologia Estrutural e Geomorfologia Tectônica. Esta bacia tipo gráben encontra-se encaixada na estrutura pretérita NE-SW do embasamento pré-cambriano, composto de gnaisse bandado milonítico da Unidade Arcádia-Areal, juntamente com ortognaisses e granitoides do Arco Magmático Rio Negro. Essas rochas estão intrudidas por diques de diabásio cretáceos de direção NE-SW. O registro sedimentar está associado, principalmente, aos depósitos aluvionares e coluvionares, que se estendem por 20 km de comprimento por 9 km de largura, expostos de maneira irregular e separados por altos intrabacinais. As características da rede de drenagem e do relevo da área, somados aos inúmeros e persistentes lineamentos, mostram, em conjunto com os dados levantados em campo, que os traços principais se associam às fraturas. O GRL é uma estrutura alongada e estreita delimitada por falhas NE-SW, em ambas as bordas, e compartimentada fundamentalmente por fraturas de direção NW-SE e E-W. O primeiro evento de formação do GRL se relaciona com as falhas normais NE-SW do embasamento, equivalente ao processo de geração das bacias do Sistema de Riftes Cenozoicos do Sudeste do Brasil... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Ribeirão das Lajes Graben (RLG) was mapped at the boundary between Serra do Mar escarpments and Guanabara Graben, in the state of Rio de Janeiro, Brazil. The present study aimed to characterize the Cenozoic tectonic evolution and shape of RLG from methods which incorporate procedures in laboratory and field work, involving structural geology and tectonics geomorphology. This basin was developed on thrust-sheared precambrian NE-SW substrate, consisting of banded milonytic gneisses from the Arcadia-Areal Unit, along with orthognaisses and granitoids from the Rio Negro Magmatic Arc. These rocks are intruded by cretaceous diabase dikes with NE-SW direction. The sedimentary record is mainly associated with alluvial and colluvial deposits, extending 20 km long and 9 km wide, irregularly exposed and separated by intrabacinal highs. The drainage network and relief characteristics, added to the numerous and persistent lineaments, even along with the data collected in the field, demonstrate that the main features are associated to fractures. This elongated and narrow graben is delimited by NE-SW faults at both edges, in addition to NW-SE and E-W fractures which compartmentalize it. The RLG was formed due to recognized NE-SW normal faults, event related to Cenozoic Rift System of Southeastern Brazil generation process. NE-SW structures are expressive in the fluvial system, morphotectonic pattern and preferential erosion and sedimentation zones. In a local scale, field-recognized high-an... (Complete abstract click electronic access below)
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Mkrtchyan, Mushegh. "Analyse cinématique et paléosismologique des terminaisons NW et SE de la faille Pampak-Sevan-Syunik (PSS), Arménie". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT152/document.

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L’Arménie se situe dans la zone de collision entre Arabie et Eurasie et est le siège d’une déformation intracontinental active comme l’atteste les nombreux tremblements de terre historiques qui s’y sont produits. Tous ces séismes, destructeurs, attestent d’une forte activité sismique régionale, et il est par conséquent important d'évaluer l’aléa sismique associé aux structures actives qui génère cette sismicité.Le travail présenté ici, expose les résultats de l’analyse de la tectonique active au niveau des terminaisons nord-ouest et sud-est de la faille de Pambak-Sevan-Syunik (PSSF), une des failles décrochant majeure qui traverse l'Arménie du NW au SE. La quantification des déformations en termes de géométrie, cinématique, vitesse de glissement et paléosismicité, en utilisant les méthodes de datation 3He cosmogénique, OSL/IRSL et radiocarbone, révèlent des comportements différents entre les deux régions.Au niveau de la terminaison nord-ouest, dans la région d’Amassia, la faille PSSF s’incurve vers l'ouest et se subdivise en deux branches de direction WNW-ESE, et de cinématique inverse, définissant une structure en pop-up. Nous estimons une vitesse de soulèvement de 0.5 ± 0.1 mm/an et une vitesse de raccourcissement NNE-SSW de 1.4 ± 0.6 mm/an. Ces résultats suggère que l’essentiel des ~2 mm/an de mouvement dextre estimés le long de la faille de PSSF sont absorbés au niveau du pop-up d’Amassia.Au niveau de la terminaison sud-est, dans la région du volcan Tsghuk, la faille PSSF semble disparaitre. Le peu d’activité tectonique est caractérisée par des failles normales sub-méridiennes associées à une légère composante décrochant dextre. Nous déterminons une vitesse de glissement vertical de ~0,2 mm/an, une vitesse d’extension ~EW de ~0,1 mm/an associée à une composante dextre de ~0,05 mm/an. Ces résultats suggèrent que le mouvement dextre observé le long de la faille de PSSF plus au nord, a été transféré sur d'autres failles plus à l'ouest dans le Karabakh (faille Hagari ou autres structures situés encore plus au NW)
The territory of Armenia was located in the collision zone between Arabia and Eurasia, and is the seat of active intercontinental deformations, which was attested by the many historical earthquakes that have occurred in this region. All these destructive earthquakes show a strong regional seismic activity, and therefore it is important to evaluate the seismic hazard associated with active structures that generates this seismicity.This study presents the results of the analysis of the active tectonics within the northwestern and southeastern extensions of the Pambak-Sevan-Syunik fault (PSSF), a major right-lateral strike-slip fault cutting through Armenia (NW - SE). Quantifying the deformations in terms of geometry, kinematics, slip rates and earthquake activity, using cosmogenic 3He, OSL/IRSL and radiocarbon dating techniques, reveal different behaviors between the two regions.Within the northwestern extension, in the region of Amassia, the PSSF bends to the west and splits into two main WNW-ESE trending reverse faults defining a compressional pop-up structure. We estimate an uplift rate and a shortening rate of 0.5 ± 0.1 mm/y and 1.4 ± 0.6 mm/y, respectively. This suggests that most of the ~2 mm/y right lateral movement of the PSSF seems to be absorbed within the Amasia pop-structure.Within the southeastern extension, in the region of Tsghuk volcano, the PSSF shows signs of dying out at the southernmost tip of the Syunik graben. A very slow NS trending normal faulting associated with a slight right-lateral movement characterizes the tectonic activity in the region of Tsghuk volcano. We estimate vertical slip rates, EW stretching rate, and right-lateral slip rate of ~0.2 mm/y, ~0.1 mm/y and ~0.05 mm/y, respectively. These results lead to the conclusion that the right lateral movement observed further north along the PSSF is mainly transferred within other active faults further west within the Karabagh (Hagari fault or other structures further northwestwards)

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Roldan, Luiz Fernando. "Tectônica rúptil meso-cenozóica na região do Domo de Lages, SC". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-31072007-155414/.

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Este trabalho tem como objetivo discutir a evolução tectônica meso-cenozóica do Domo de Lages, SC, envolvendo análise das estruturas rúpteis que afetam as rochas da região, análise morfométrica e da rede de drenagem e aspectos geomorfológicos relevantes. O Domo de Lages, localizado na borda leste da Bacia do Paraná, na porção sul do estado de Santa Catarina, é caracterizado pela ocorrência de uma grande variedade de rochas alcalinas de idade neo-cretácea. Estas rochas afloram na forma de sills e diques e são intrusivas no pacote sedimentar da Bacia do Paraná, causando-lhe um soerguimento da ordem de centenas a milhares de metros. As rochas alcalinas foram afetadas por estruturas rúpteis, particularmente falhas transcorrentes e normais, denotando a presença de uma tectônica ativa durante o cenozóico. Para o entendimento do quadro evolutivo do domo, além da análise estrutural, foram elaborados diversos mapas morfométricos (hipsométrico, declividades, orientação de vertentes, superfícies de base, rugosidade, gradiente hidráulico e densidade de lineamentos e drenagens) derivados diretamente do Modelo Digital de Elevação, que por sua vez foi obtido pelo tratamento de dados SRTM (Shuttle Radar Topographic Mission) da Agência Espacial Americana (NASA). O trabalho foi complementado com a análise da rede de drenagem e de lineamentos extraídos de imagens, juntamente com a elaboração de perfis topográficos. Os resultados mostram tratar-se de uma estrutura dômica alongada com eixo maior orientado na direção NW-SE, marcada pelo alinhamento de intrusões alcalinas e basculamento dos acamamentos das rochas sedimentares que apresentam mergulho radial para fora da estrutura. A análise do relevo revelou a existência de uma superfície de aplainamento, hoje preservada na cota de 1200 m, que teria sido afetada por falhas normais de direções NW-SE e NE-SW. O modelo tectônico evolutivo elaborado para a região contempla a seguinte seqüência de eventos: atuação de esforços compressivos NE-SW no final do cretáceo, gerando falhas normais NE-SW, que afetam as rochas básicas da Formação Serra Geral e condicionam a colocação de diques alcalinos e a estruturação do domo; geração de falhas transcorrentes destrais que afetam todas as rochas da região, incluindo as rochas alcalinas, com binário orientado na direção NNE-SSW; configuração de uma superfície de aplainamento preservada na cota de 1200m, que perdurou, provavelmente, até o mioceno; distensão NE-SW e geração de falhas normais NW-SE que abatem e basculam a superfície aplainada e reorganizam a rede de drenagens; instalação de um provável evento distensivo NW-SE, responsável pela formação de falhas normais NE-SW, marcadas principalmente nos mapas morfométricos.
This study was focused on the meso-cenozoic tectonic evolution of the Domo de Lages region (south Santa Catarina State, Southern Brazil), through the analysis of brittle structures affecting sedimentary and igneous rocks, morphometric parameters, drainage network and main geomorphological features. Located in the border of the Paraná sedimentary basin, the Domo de Lages is characterized by a great variety of Late Cretacic alkaline rocks, which crops out as sills and dikes cutting the Paleozoic sedimentary rocks, and are associated with an uplift of hundreds to thousands of meters. These alkaline rocks are affected by brittle structures, mainly transcurrent and normal faults, indicative of Cenozoic active tectonics. In addition to the structural analysis, several morphometric maps were developed, as an aid to enlighten the evolutionary history of the region. Maps of hypsometry, slope, aspect, isobase surfaces, surface roughness, hydraulic gradient, lineament density and drainage density were derived from SRTM (Shuttle Radar Topographic Mission) Digital Elevation Models provided by NASA, and were complemented by topographic profiles, analysis of drainage network and lineament orientation. Results show that the dome has a elongated shape with major axis oriented NW-SE, defined by alignment of intrusive bodies and tilting of sedimentary rocks bedding planes, dipping radially outwards the center of the structure. Topographic analysis revealed the existence of a planation surface, preserved at 1200m a.s.l., wich would have been affected by NW-SE and NE-SW normal faults. A tectonic evolutionary model for the region was elaborated, according the following sequence of events: in the end of Cretaceous, a compressive NE stress generates NE-SW normal faults, which affect the basic rocks of Serra Geral Formation and controls the emplacement of alkaline dikes and the uplift of the domic structure; formation of transcurrent dextral faults affecting all rocks of the area, including the alkalines, with NNE-SSW oriented binary; development of a planation surface preserved at 1200m a.s.l. which remained probably until the Miocene; NE-SW extension, creating NW-SE normal faults that lowered and tilted the levelled surface and affected the drainage network; a last extensive NW-SE event probably happened, responsible for NE-SW normal faults seen mainly in the morphometric maps.

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Souza, Alexandre dos Santos. "Caracterização geomorfológica, morfotectônica e morfométrica da Folha Itapororoca 1:25.000, Paraíba, Brasil". Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/9859.

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This study aimed to analyze the interrelation ships between geology, relief and hydrography of the area of Itapororoca sheet (SB.25-YAV-4-NO), at scale 1:25,000, with equidistance between the contour lines of 10m, in the state of Paraiba, demonstrating how there lief of the are a shows clear influence of structural control on the configuration of relief and drainage network. From this perspective, it is emphasized that the know ledge of geomorphological features is an in dispensable way for the elaboration of plans geared to various purposes, such as: engineering works, environmental issues, agricultural development, mineral exploration, among others. The integrated analysis of morphostructural peculiarities present in relief and river drainage systems, allowed to infer about the role of tectonic deformations that occur through structural efforts, revealing numerous morphostructural features in the sedimentary covers and the grounds of the Precambrian crystalline basement. The research was conspicuous by analyzing the qualitative and quantitative aspects of geomorphology and drainage network, with the aid of cartographic products and the application of morphometric indices. The development of cartographic material, essential for qualitative analysis, consisted in the confection of hypsometric, slope and geomorphology thematic maps, Digital Elevation Model (DEM) and topographic profiles. The quantitative evaluation and neotectonics consisted of application of morphometric parameters of Slope/Length (SL), Valley Floor Width/Valley Height (VF) Ratio and Asymmetrical Factor (AF).The thematic maps and MDE were generated by specific software, based on data extracted from Itapororoca sheet 1:25,000 by manual vectorization, which allowed unprecedented detail of the geomorphological and hydrographic pattern present in the area. The results exposed several anomalies in the study area, for example, altimetric discrepancies present in the area of geological unit Itapororoca Felsic Volcanic Rock (northwestern) and Trays (northeast portion), indicating that the region was affected by faulting and compressive efforts that defined several anomalies, such as: anomalous rectilinear drainage patterns, lattice and associated subtypes; abrupt channels inflections forming orthogonal angles; isolated and compressed meanders; and morphostructural faulting with guidance compatible with regional tectonic structures in northeastern Brazil. Substantiating the evidence, the values obtained with the application of morphometric parameters showed that neotectonic events affected the drainage network of the study area. Thus, it is concluded that the combined analysis of the studied elements made blunt results about neotectonics performance that configures morphotectonic environments and drainage anomalies in the area of Itapororoca sheet 1:25,000.
Esta pesquisa objetivou analisar as inter-relações existentes entre a geologia, o relevo e a hidrografia da área da folha Itapororoca (SB.25-Y-A-V-4-NO), na escala de 1:25.000, com equidistância entre as curvas de nível de 10m, no estado da Paraíba, demonstrando como o relevo da área apresenta nítida influência de controle estrutural na configuração do relevo e da rede de drenagem. Nessa perspectiva, ressalta-se que o conhecimento das feições geomorfológicas representa um meio indispensável para elaboração de planejamentos voltados aos mais diversos fins, como: obras de engenharia, questões ambientais, desenvolvimento agrícola, exploração mineral, entre outros. A análise integrada das particularidades morfoestruturais presentes no relevo e nos sistemas de drenagem fluvial, permitiu inferir acerca do papel das deformações tectônicas ocorridas mediante esforços estruturais, revelando inúmeras feições morfoestruturais nas coberturas sedimentares e nos terrenos do embasamento cristalino pré-cambriano.A pesquisa primou por analisar os aspectos qualitativos e quantitativos da geomorfologia e da rede de drenagem, com o auxílio de produtos cartográficos e da aplicação de índices morfométricos. A elaboração do material cartográfico, fundamental para análise qualitativa, consistiu na confecção das cartas temáticas hipsométrica, clinográfica e geomorfológica, do Modelo Digital de Elevação (MDE) e dos perfis topográficos. Já a avaliação quantitativa e a neotectônica consistiram em aplicaçãode parâmetros morfométricos de Relação Declividade/Extensão (RDE), Razão Fundo/Altura de Vale (RFAV) e Fator Assimétrico (FA). Geraram-se as cartas temáticas e o MDE mediante softwaresespecíficos, com base em dados extraídos da folha Itapororoca 1:25.000 por meio de vetorização manual, o que permitiu detalhamento inédito do padrão geomorfológico e hidrográfico presente na área. Os resultados obtidos expuseram diversas anomalias na área de estudo, como, por exemplo, as discrepâncias altimétricas presentes na área da unidade geológica da Rocha Vulcânica Félsica Itapororoca (porção noroeste) e nos Tabuleiros (porção nordeste), indicando que afetaram a região falhamentos e esforços compressivos que definiram diversas anomalias, como: padrões de drenagem anômalos retilíneos, em treliça e subtipos associados; inflexões abruptas de canais formando ângulos ortogonais; meandros isolados e comprimidos; e falhamentos morfoestruturais com orientação compatível com estruturas tectônicas regionais do nordeste brasileiro. Fundamentando essas evidências, os valores obtidos com a aplicação dos parâmetros morfométricos mostraram que eventos neotectônicos afetaram a rede de drenagem da área de estudo. Dessa forma, conclui-se que a análise combinada dos elementos estudados apresentouresultados contundentes acerca da atuação neotectônica que configura os ambientes morfotectônicos e as anomalias da drenagem na área da folha Itapororoca 1:25.000.

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Maréchal, Anaïs. "Tectonique active de la zone de collision Yakutat - Nord Amérique : apport du GPS et de la géomorphologie à l'étude de la partition de la déformation". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS282.

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Au SO Yukon – SE Alaska, la frontière entre les plaques Pacifique et Nord-Amérique est marquée par une syntaxe à la transition entre la subduction des Aléoutiennes à l'O et le décrochement de Fairweather – Queen Charlotte au SE. Le mouvement relatif est oblique et la région est marquée par la collision du bloc Yakutat. De la chaine des Chugach – Saint Elias en frontière de plaque (jusqu'à 6 000 m d'altitude) aux grands décrochements intraplaque, les marqueurs de la déformation actuelle apportent des informations sur sa partition dans ce système. Au cours de cette thèse, je m'intéresse dans un premier temps à mesurer la déformation de surface à l'aide d'un réseau GPS dense, déployé jusqu'à 500 km à l'intérieur de la plaque Nord-Amérique. Après un travail minutieux de traitement des données et de correction des effets transitoires (rebond post-glaciaire et post-sismique), un champ de vitesses résiduelles robuste et inédit est produit au niveau de la syntaxe, dont je dérive des taux de déformation. Ces données me permettent de quantifier les vitesses de glissement les failles décrochantes de Fairweather et Denali au Sud, et également de caractériser une déformation bi-modale : En frontière de plaques, la déformation est localisée sur les grandes structures (prisme d'accrétion à l'O, Fairweather à l'E) ; Au niveau de la syntaxe, les taux de déformation sont les plus importants et les données GPS mettent en évidence une déformation intraplaque diffuse, similaire à un champ attendu à l'aplomb d'un indenteur. Le bloc Yakutat semble donc contrôler fortement la déformation de la plaque Nord-Amérique.Ce champ de déformation induit des variations latérales fortes sur les grandes failles intraplaque : le système Denali-Totschunda-Duke River. Dans une seconde partie, je réalise une étude géomorphologique régionale pour caractériser le rôle et la vitesse de ces failles. À partir de Modèles Numériques de Terrain très haute résolution (~ 1 m), une cartographie de détail est réalisée. Puis une mission de terrain me permet de mesurer des décalages sur des marqueurs fluviatiles et glaciaires et collecter des échantillons pour les dater. Je mets en évidence une déformation cumulée dextre sur le segment Nord de la faille de Denali, alors que toute la partie Sud déforme verticalement la surface. Cette étude me permet de quantifier de nouvelles vitesses de failles sur le système Denali-Totschunda-Duke River, et de montrer le rôle prépondérant des failles de Totschunda (~ 14 mm/a) et Duke River (~ 6 mm/a) contrairement à la faille de Denali (~ 1 mm/a) au Nord de la syntaxe.Le nouveau modèle cinématique proposé pour la région de collision Yakutat permet d'apporter un nouvel exemple à la compréhension des systèmes d'indenteur. La concomitance d'une déformation de blocs (à l'Ouest) et diffuse (à l'Est), ainsi que l'absence de déformation sur la faille lithosphérique de Denali Sud met en évidence le contrôle majeur des conditions aux limites et de l'héritage structural dans la déformation des orogènes
In SW Yukon – SE Alaska, the boundary between the Pacific and North America plates is characterized by a syntaxis at the transition between the Aleutian subduction to the W and the Fairweather – Queen Charlotte strike-slip faults to the SE. The relative motion is oblique to the main fault structures, and the area is marked by the Yakutat block collision. From the Chugach – Saint Elias mountains in the plate boundary zone (up to 6 000 m high) to the intraplate strike-slip faults, markers of the present-day deformation give information on its partition in the system.During my PhD, I first measure surface deformation using a dense GPS network, deployed up to 500 km inland the North America plate. After precise processing and corrections of transient effects in the area (postseismic and glacial isostatic rebound), a new residual velocity field is produced for the syntaxis area, from which I derive strain rates. Those data allow me to quantify the fault slip rates for Fairweather and southern Denali strike-slip faults, and to characterize a bi-modal deformation pattern: Along the plate boundary, the deformation is localized on large-scale structures (accretionary prism to the W, Fairweather to the E); In the syntaxis area, strain rates are the highest and the GPS data shows a diffuse intraplate deformation, similar to an indentor pattern. The Yakutat block seems to strongly drive the North America plate deformation.This indentor pattern induces strong lateral variations on the large intraplate faults: the Denali – Totschunda – Duke River system. In a second part, I realize a regional geomorphological study to characterize the role and slip rate of those faults. From very high-resolution Digital Elevation Models (~ 1 m), a detailed cartography is done. On the basis of fieldwork observations, I measure offsets of fluvial and glacial markers, which are sampled for dating. A dextral cumulative deformation is highlighted on the northern Denali Fault, where as all southern Denali is marked by vertical deformation. This study allows me to quantify new slip rates for the system Denali – Totschunda – Duke River, and to show the leading role of the Totschunda (~ 14 mm/a) and Duke River (~ 6 mm/a) faults, contrary to the Denali Fault (~ 1 mm/a) North of the syntaxis.The new tectonic model for the Yakutat collision provides an important case study for the understanding of indentor systems. The concomitance of a rigid-block deformation (to the West) and diffuse deformation (to the East), as well as the near-zero slip rate on the lithospheric-scale southern Denali Fault highlight the major control of boundary conditions and the structural heritage on the orogen deformation

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Ding, Min Ph D. Massachusetts Institute of Technology. "Lithospheric dynamics of Earth's subduction zones and Martian tectonic provinces". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97340.

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Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references.
This thesis investigates lithospheric dynamics of Earth's subduction zones and Martian tectonic provinces on multiple time scales ranging from short-term earthquake deformation to long-term tectonic loading. In Chapter 2, I use geodetic observations to constrain the postseismic viscoelastic deformation following the 1960 M9.5 Valdivia, Chile earthquake and quantify its stress loading on the rupture zone of the 2010 M8.8 Maule, Chile earthquake. Results of analysis reveal that the post-1960 viscoelastic process might have contributed to the triggering of the 2010 earthquake. Chapter 3 presents numerical experiments to investigate elastoplastic deformation and faulting in the overriding plates of subduction zones caused by the movement of subducted seamounts. Numerical simulations show that a group of normal faults would first appear on the seaward side of a subducted seamount, followed by a group of thrust faults on the landward side of the seamount. In Chapter 4, I use the most recent Martian gravity and topography data to constrain spatial variations in lithospheric flexural deformation for various tectonic regions on Mars. The effective lithospheric thickness is estimated to be relatively small for the plain regions in the southern highland, but relatively large for the impact basins in the northern lowland as well as for volcanic montes in the Tharis province. The regional variations in the estimated effective lithospheric thickness might reflect both spatial and temporal changes in the thermal state of Mars.
by Min Ding.
Ph. D.

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Le, Roux-Mallouf Romain. "Déformation Holocène de l’Himalaya du Bhoutan : apport de la géomorphologie et de la paléosismologie". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT142/document.

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La chaîne Himalayenne est l'un des exemples les plus spectaculaires de déformation active à la surface de notre planète. Au cours des derniers siècles, de nombreux séismes majeurs (Mw > 7.5) ont affecté cette zone et le lourd bilan humain du séisme de Gorkha en 2015 a une nouvelle fois rappelé l’importance de parvenir à mieux estimer l’aléa sismique de cette région. Bien que les structures lithologiques et tectoniques semblent montrer au premier ordre une cylindricité le long des 2500 km de l'arc Himalayen, de nombreuses études, menées principalement au Népal, ont permis de mettre en évidence des variations latérales structurales, thermochronologiques, morphologiques, gravimétriques, sismologiques ou géodésiques. Le rôle de ces variations latérales sur la segmentation sismique reste cependant mal contraint. La taille maximale et la probabilité d’occurrence de ces méga-séismes sont donc toujours matière à débat.Ainsi, le comportement sismique de l’Himalaya du Bhoutan reste énigmatique. Pour certains les faibles taux de sismicité observés actuellement font de ce royaume une zone asismique de 350 km de long. Pour d’autres, à l’instar de l’Himalaya du Népal, la faible sismicité observée est associé à une forte accumulation de contrainte susceptible de générer des séismes majeurs. L'objectif de ce travail de thèse est d’améliorer notre connaissance de cette région en quantifiant la déformation à différentes échelles spatiales et temporelles via des études morphotectoniques et paléosismologiques.La première partie de cette thèse vise à quantifier les mouvements verticaux à l’ouest Bhutan et le long du Main Frontal Thrust, structure la plus frontale située au sud Bhoutan. Trois campagnes de terrain ont été réalisées permettant l'échantillonnage (1) de terrasses alluviales le long du front afin de quantifier et d'étudier les variations du soulèvement Holocène, (2) de bassins versants pour l'étude de la dénudation court-terme (< 20 ka) dérivée des cosmonucléides ($^{10}$Be) et (3) de terrasses alluviales dans le Moyen-Pays pour quantifier l’incision Holocène. Les vitesses verticales obtenues au front sont comparables à celle proposées le long du reste de l’arc himalayen, suggérant une cinématique relativement simple. Par contre, nos résultats indiquent une variation de la géométrie du chevauchement himalayen (Main Himalayan Thrust) entre l’est Népal et l’ouest Bhoutan.La seconde partie porte sur plusieurs études paléosismologiques le long du front ouest et centre Bhoutanais. Six sites différents ont été étudiés au cours de trois campagnes de terrain. La datation et la modélisation de charbons détritiques a permis de mettre en évidence l'occurrence d’au moins cinq séismes majeurs durant les derniers 2700 ans, faisant du Bhoutan une zone sismiquement aussi active que le Népal. A une échelle régionale, cette étude apporte donc de nouvelles contraintes et contribue au débat sur la possibilité d’occurrence d'un séisme de magnitude 9 le long de l'arc Himalayen
The Himalayan arc is one of the most active intra-continental mountain belts in the world. Over the last centuries, several major earthquakes (Mw > 7.5) have struck this arc. The dramatic effects of the Gorkha earthquake sequence in 2015 pointed once again the crucial need to improve seismic hazard assessment of this area.Geological explorations of the Himalayas since the late 19th century have emphasized a 2500-km-long roughly cylindrical structure, with striking continuity of main units and thrust faults. However recent geophysical and geological investigations have revealed lateral variations. The relationship between these variations and earthquakes segmentation along the arc remains poorly constraint. The maximum size and the occurrence probability of such earthquakes are still a matter of debate.For instance, the seismic behavior of Bhutan remains enigmatic. The present-day low seismicity rate observed in this area can reflect two opposite fault behaviors: an aseismic creeping zone or a zone of stress accumulation for future great earthquakes as the others parts of Himalayas. The main objective of this thesis is to bring new constraints on the deformation of the Bhutan Himalayas, at different space- and time-scales, through morphotectonic and paleoseismological approaches.The first part of this thesis focuses on the vertical deformation assessment along a N-S transect in western Bhutan and along the Main Frontal Thrust, which is the southern-most thrust in southern Bhutan. In the past three years, we have carried out three fieldwork campaigns to sample (1) frontal terraces to assess Holocene uplift rates, (2) watershed basins to quantify short term denudation rates (< 20 ky) derived from cosmonuclides $^{10}$Be and (3) hinterland alluvial terraces to quantify the Holocene incision rate. Frontal Holocene uplift rates obtained in Bhutan are consistent with those obtained in the others parts of Himalayas. Furthermore, our results reveal a variation in the geometry of the Main Himalayan Thrust between eastern Nepal and western Bhutan.The second part focuses on several paleoseismic studies along the west and central bhutanese Himalayan front. Different sites were investigated during three fieldwork campaigns. Detritic charcoals sampling and modeling suggest the occurrence of at least five surface-rupturing earthquakes during the last ~2700 years. These results demonstrate that the present-day low seismicity rate observed in Bhutan is not representative of the seismic activity at longer time scale. At regional scale, they also take part of a broader discussion on the probability of occurrence of a magnitude 9 earthquake along the Himalayan arc

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Rosenbaum, Gideon. "Tectonic reconstruction of the Alpine orogen in the western Mediterranean region". Monash University, School of Geosciences, 2003. http://arrow.monash.edu.au/hdl/1959.1/9481.

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Paquet, Fabien. "Morphostructural evolution of active margin basins : the example of the Hawke Bay forearc basin, New Zealand : a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Geology at the University of Canterbury /". Thesis, University of Canterbury. Geological Sciences, 2007. http://hdl.handle.net/10092/1474.

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Topography growth and sediment fluxes in active subduction margin settings are poorly understood. Geological record is often scarce or hardly accessible as a result of intensive deformation. The Hawke Bay forearc basin of the Hikurangi margin in New Zealand is well suited for studying morphstructural evolution. It is well preserved, partly emerged and affected by active tectonic deformation during Pleistocene stage for which we have well dated series and well-known climate and eustasy. The multidisciplinary approach, integrating offshore and onshore seismic interpretations, well and core data, geological mapping and sedimentological sections, results in the establishment of a detailed stratigraphic scheme for the last 1.1 Ma forearc basin fill. The stratigraphy shows a complex stack of 11 eustasy-driven depositional sequences of 20, 40 and 100 ka periodicity. These sequences are preserved in sub-basins that are bounded by active thrust structures. Each sequence is characterized by important changes of the paleoenvironment that evolves between the two extremes of the glacial maximum and the interglacial optimum. Thus, the Hawke Bay forearc domain shows segmentation in sub-basins separated by tectonic ridges during sea level lows that become submerged during sea level highs. Over 100 ka timescale, deformation along active structures together with isostasy are responsible of a progressive migration of sequence depocenters towards the arc within the sub-basins. Calculation of sediment volumes preserved for each of the 11 sequences allows the estimation of the sediment fluxes that transit throughout the forearc domain during the last 1.1 Ma. Fluxes vary from c. 3 to c. 6 Mt.a⁻¹. These long-term variations with 100 ka to 1 Ma timescale ranges are attributed to changes in the forearc domain tectonic configuration (strain rates and active structure distribution). They reflect the ability of sub-basin to retain sediments. Short-term variations of fluxes (<100 ka) observed within the last 150 ka are correlated to drastic Pleistocene climate changes that modified erosion rates in the drainage area. This implies a high sensitiveness and reactivity of the upstream area to environmental changes in terms of erosion and sediment transport. Such behaviour of the drainage basin is also illustrated by the important increase of sediment fluxes since the European settlement during the 18th century and the following deforestation.

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Hiruma, Silvio Takashi. "Significado morfotectônico dos planaltos isolados da Bocaina". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/44/44134/tde-18122007-141938/.

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O Planalto da Bocaina situa-se no flanco leste do Rift Continental do Sudeste do Brasil (RCSB), em uma das porções mais elevadas da Serra do Mar, com altitudes superiores a 2000 m, compondo, juntamente com o Planalto de Campos do Jordão, os altos blocos de planaltos cristalinos do sudeste do Brasil. A Bocaina apresenta uma sucessão de planaltos de relevo mais suavizado (planaltos isolados), separados por vales profundos, que perdem altura de NW para SE. A origem do desnivelamento desses planaltos tem sido associada ora à reativação de antigas zonas de cisalhamento por falhas com componente normal, ora à dissecação erosiva diferencial controlada por knickpoints, ou, ainda, à preservação de superfícies de erosão de idades diferentes. A presente pesquisa teve por finalidade analisar as diferentes hipóteses de modo a estabelecer a idade, estilo e magnitude dos eventos tectônicos e denudacionais, responsáveis pela atual distribuição dos planaltos isolados da Bocaina. A metodologia integra estudos geomorfológicos e estruturais, segundo uma abordagem morfotectônica, com apoio da análise de traços de fissão em apatita e determinações pelo método do radiocarbono. Esta análise constitui importante ferramenta para determinar histórias térmicas e idades de resfriamento, em escalas de tempo de 106 a 108 anos, e permite estimar taxas de denudação de blocos de embasamento. Modelos digitais de terreno e cartas morfométricas subsidiaram a análise morfotectônica. Os planaltos isolados são caracterizados por baixos valores de gradientes hidráulicos, declividade e amplitude do relevo. O condicionante tectônico no desnivelamento dos níveis topográficos e individualização desses planaltos é evidenciado pela estreita correlação entre estruturas rúpteis (falhas e fraturas), feições morfotectônicas (facetas triangulares, knickpoints, escarpas, capturas fluviais), distribuição dos principais alvéolos e padrão de drenagem. Diques registram fases distensivas desde a ruptura dos continentes no Eocretáceo até o Paleógeno. Regimes de esforços observados na Bocaina são compatíveis com o modelo tectônico proposto para o RCSB durante o Cenozóico. Os eventos tectono-magmáticos no sudeste do Brasil tiveram um importante papel nos processos denudacionais registrados pela análise de traços de fissão em apatitas no Planalto da Bocaina. As idades corrigidas de traços de fissão em apatitas para 15 amostras variam entre 326±30 e 54±5 Ma, incluindo um significativo conjunto de idades mais velhas do que 200 Ma - as mais antigas obtidas na região da Serra do Mar até o momento. As idades apresentam uma tendência de decréscimo de noroeste para sudeste, do interior do continente em direção à costa, padrão também reconhecido em outras margens continentais passivas. Esse padrão é perpendicular à direção estrutural principal do embasamento pré-cambriano, sugerindo um importante condicionante estrutural. Idades contrastantes em um mesmo planalto isolado, ou similares em altitudes diferentes, sugerem uma evolução tectonotermal regional complexa, possivelmente associada à evolução do RCSB. Um modelo simples de recuo de escarpa não explicaria a distribuição espacial das idades de traços de fissão em apatitas no Planalto da Bocaina; falhas devem ter sido responsáveis pela acentuação dos desníveis topográficos entre os planaltos isolados. As histórias térmicas registram importantes eventos de resfriamento relacionados à ruptura continental, ao magmatismo alcalino neocretáceo e à geração e deformação do RCSB. As idades mais antigas de traços de fissão da Serra do Mar foram obtidas nas porções mais elevadas da Bocaina, que guardam estreita semelhança com a paisagem dos altos campos no Planalto de Campos do Jordão, evidenciando que tais áreas provavelmente constituíram, por um longo período de tempo, importante área fonte de sedimentos para as bacias do Paraná, Bauru e Santos.
The Bocaina Plateau is situated on the eastern flank of the Continental Rift of Southeastern Brasil (CRSB), in the highest portions of the Serra do Mar, reaching more than 2000 meters in altitude. This and the Campos do Jordão Plateau comprise the high blocks of crystalline massifs of Southeastern Brasil. The Bocaina presents a succession of NW-SE topographically decreasing low-relief plateaus (isolated plateaus), separated by deep valleys. The origin of the differences in altitude among these plateaus has been associated with (1) tectonic reactivation of ancient shear zones by normal faulting, (2) differential erosional dissection controlled by knickpoints, and (3) preservation of erosional surfaces of different ages. This study examines these hypotheses in order to establish the age, style and magnitude of the tectonic and denudational events that resulted in the current distribution of the isolated plateaus of Bocaina. Structural and geomorphological analyses have been carried out using a morphotectonic approach, aided by apatite fission track analysis and radiocarbon dating. Apatite fission track analysis is an important tool to obtain thermal histories and cooling ages, on scales of 106 to 108 years, and is commonly used to estimate denudation rates in basement blocks. Morphotectonic analysis was supported by digital terrain models and morphometric maps. The isolated plateaus are characterized by low hydraulic gradient, slope and relief. Tectonic conditioning in the accentuation of differences in altitude and individualization of the plateaus is evinced by clear correlation between brittle structures (faults and fractures), morphotectonic features (triangular facets, knickpoints, scarps, fluvial captures), distribution of main alluvial plains and drainage pattern. Dikes indicate distensional phases since continental break-up in the Early Cretaceous till the Paleogene. Stress regimes observed in Bocaina are compatible with the tectonic model for the CRSB during the Cenozoic. Tectonic and magmatic events in Southeastern Brazil played an important role in denudational processes as recorded by apatite fission track analysis in the Bocaina plateau. Corrected fission track ages for 15 samples range from 326±30 to 54±5 Ma, including a significant set greater than 200 Ma, the oldest such ages yet registered in the Serra do Mar. Ages decrease NW-SE from the continent coastwards, a trend also recognized in other passive continental margins. This pattern is perpendicular to the main structural grain of the Precambrian basement, suggesting important structural control. Contrasting ages within a single plateau and similar ages at different altitudes indicate complex regional tectono-thermal evolution, possibly related to the evolution of the CRSB. Fission track age distribution in the Bocaina plateau cannot be explained by the simple scarp-retreat model; faults must have accentuated differences in altitude among the isolated plateaus. Thermal histories show important cooling events related to continental break-up, Early Cretaceous alkaline magmatism and origin of the CRSB. The oldest fission track ages obtained in the Serra do Mar region (> 200 Ma) were found in the highest portions of the Bocaina plateau, where the landscape system is very similar to that of the Campos do Jordão plateau. These areas have probably been an important, persistent source of sediments for the Paraná, Bauru and Santos basins, for a very long time.

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Muller, Stefan G. "The tectonic evolution and volcanism of the Lower Wyloo Group, Ashburton Province, with timing implications for giant iron-ore deposits of the Hamersley Province, Western Australia". University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0043.

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[Truncated abstract] Banded iron formations of the ~27702405 Ma Hamersley Province of Western Australia were locally upgraded to high-grade hematite ore during the Early Palaeoproterozoic by a combination of hypogene and supergene processes after the initial rise of atmospheric oxygen. Ore genesis was associated with the stratigraphic break between Lower and Upper Wyloo Groups of the Ashburton Province, and has been variously linked to the Ophthalmian orogeny, late-orogenic extensional collapse, and anorogenic continental extension. Small spot PbPb dating of in situ baddeleyite by SHRIMP (sensitive highresolution ion-microprobe) has resolved the ages of two key suites of mafic intrusions constraining for the first time the tectonic evolution of the Ashburton Province and the age and setting of iron-ore formation. Mafic sills dated at 2208 ± 10 Ma were folded during the Ophthalmian orogeny and then cut by the unconformity at the base of the Lower Wyloo Group. A mafic dyke swarm that intrudes the Lower Wyloo Group and has close genetic relationship to iron ore is 2008 ± 16 Ma, slightly younger than a new syneruptive 2031 ± 6 Ma zircon age for the Lower Wyloo Group. These new ages constrain the Ophthalmian orogeny to the period <2210 to >2030 Ma, before Lower Wyloo Group extension, sedimentation, and flood-basalt volcanism. The ~2010 Ma dykes present a new maximum age for iron-ore genesis and deposition of the Upper Wyloo Group, thereby linking ore genesis to a ~21002000 Ma period of continental extension similarly recorded by Palaeoproterozoic terrains worldwide well after the initial oxidation of the atmosphere at ~2320 Ma. The Lower Wyloo Group contains, in ascending order, the fluvial to shallow-marine Beasley River Quartzite, the predominantly subaqueously emplaced Cheela Springs flood basalt and the Wooly Dolomite, a shelf-ramp carbonate succession. Field observations point to high subsidence of the sequence, rather than the mainly subaerial to shallow marine depositional environment-interpretation described by earlier workers. Abundant hydro-volcanic breccias, including hyaloclastite, peperite and fluidal-clast breccia all indicate quench-fragmentation processes caused by interaction of lava with water, and support the mainly subaqueous emplacement of the flood basalt which is also indicated by interlayered BIF-like chert/mudstones and below-wave-base turbiditic mass-flows.

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El-Sobky, Hesham Farouk. "Remote sensing studies and morphotectonic investigations in an arid rift setting, Baja California, Mexico". [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1518.

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Casavant, Robert Ronald. "Morphotectonic investigation of the Arctic Alaska terrane: Implications to basement architecture, basin evolution, neotectonics and natural resource management". Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279894.

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This study created a new tectonic model for the Arctic Alaska terrane (AAT) by connecting attributes interpreted from surface and subsurface maps. Lineaments that cross the Brooks Range and North Slope proclaim the presence of basement fault blocks trending to the northeast that locally are aligned with streams, coast and lake shorelines, submarine canyons, and periglacial features. These landforms and anomalies reflect upward propagation of long-lived transcurrent and rift fault fabrics. Facies mapping and analysis of heat-flow effects on permafrost, and data from aeromagnetic, gravity and reflection seismic surveys, support the correlation of basement faulting with geomorphic patterns. The conjugate pattern of fault blocks, seen across Paleozoic- and Mesozoic-age passive margin sequences, resembles a piano keyboard and was inherited from older rift margin and transcurrent-transfer faults. Seismic data and North Slope oil-reservoir characteristics reveal complex fault-block boundaries, and common fault reactivation and structural inversion. The rigid North American craton in the Yukon Territory directs deformation westward leading to continued crustal indention, migration of basement blocks, and thrusting of cover rocks north of the Arctic oroclinal bend. Differential south-vergent underthrusting and uplift of the basement blocks of the North Slope plate has episodically segmented and partitioned strain across the overlying weaker north-vergent cover rocks of the North Alaskan plate. These tectonic controls have influenced the structural and geomorphic evolution of the North Slope-Brooks Range foothills region, including the formation of oil and gas reservoirs and mineral deposits.

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Vignon, Violaine. "Activité hors séquence des chevauchements dans la syntaxe nord-ouest himalayenne : apports de la modélisation analogique et quantification quaternaire par analyse morphotectonique". Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00771671.

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L'Himalaya est un prisme orogénique cylindrique, répondant dans son ensemble aux caractéristiques du prisme de Coulomb. Ainsi, la localisation de la déformation s'effectue principalement au front du prisme et les chevauchements transportés ne sont affectés que par de faibles réactivations hors séquence. Cependant, la terminaison ouest de la chaîne himalayenne, appelée syntaxe nord-ouest himalayenne, apparaît comme une singularité. Cette région correspond à une zone d'interaction entre différentes directions de déformation, avec, d'est en ouest, la chaîne du Pir Panjal au sud du bassin du Cachemire orientée NW-SE, la syntaxe d'Hazara-Kashmir et la chaîne des Salt Range orientée E-W, et la chaîne des Sulaiman Range orientée NE-SW. La séquence normale de déformation dans la syntaxe nord-ouest himalayenne n'est pas respectée : une activité hors séquence importante, caractérisée par une déformation accommodée sur des structures internes au front de la chaîne, a été mesurée dans la chaîne des Salt Range par l'étude structurale de la région. De plus, la chaîne du Pir Panjal présente une activité tectonique hors séquence à l'échelle du cycle sismique : le séisme du Kashmir de magnitude Mw = 7.6 du 8 octobre 2005 s'est produit sur la faille de Balakot-Bagh (extrémité nord-ouest du Medlicott Wadia Thrust, MWT) située à plus de 100 km du front de la chaîne. Ces observations posent deux interrogations : (i) la déformation hors séquence observée dans la syntaxe nord-ouest himalayenne à l'échelle du cycle sismique et à l'échelle long terme existe-t-elle à l'échelle intermédiaire ? (ii) la configuration géométrique de la syntaxe nord-ouest himalayenne favorise-t-elle la déformation hors séquence observée ? Pour répondre à ces questions nous avons entrepris une étude de terrain morphotectonique afin de caractériser la déformation dans la chaîne du Pir Panjal. Pour cela, nous avons cartographié le long de la rivière Chenab 7 niveaux de terrasses d'abrasion au toit du MWT, et trois événements d'aggradation régionaux que nous avons datés grâce à trois méthodes (53 échantillons 10Be, 6 OSL et 4 14C). Ces remplissages se terminent aux environs de 35 ka, 15 ka et 3.5 ka à la fin d'épisodes de moussons intenses. La topographie de ces terrasses a été mesurée grâce au GPS cinématique et une station totale, et leur déformation montre qu'il existe actuellement deux structures actives dans cette région : la structure frontale qui conduit au développement d'un anticlinal, et un grand chevauchement situé 20 km en position interne : le Riasi Thrust (portion du MWT). La majorité du raccourcissement, qui atteint 16 mm/an dans la région, est accommodée par le Riasi Thrust avec un déplacement sur la faille compris entre 10 et 14 mm/an. Le reste étant principalement accommodé sur la structure frontale. L'étude du chevauchement situé encore en position interne, le Main Boundary Thrust, a montré que cette structure n'est plus active depuis 15 ka. En parallèle, nous avons réalisé une série de 24 expériences analogiques en utilisant une boîte à sable dont la géométrie des bordures reproduit la partie externe de la syntaxe nord-ouest himalayenne et en faisant varier la rhéologie basale et les épaisseurs de matériaux. Ces expériences ont montré un important raccourcissement perpendiculaire à la direction de convergence, et une influence de cette géométrie des conditions aux limites sur la séquence de déformation : le pourcentage de déformation hors séquence est plus important dans ce cas que dans celui d'un prisme cylindrique. Notre étude montre donc que la déformation hors séquence dans la syntaxe nord-ouest himalayenne existe aussi sur une échelle de temps intermédiaire entre le cycle sismique et le long terme. Nous l'expliquons en partie comme une caractéristique de la déformation d'une forme en syntaxe. D'autres mécanismes tels que l'érosion due à de fortes précipitations locales et un héritage structural pourraient également être envisagés.

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Löbens, Stefan Verfasser], Siegfried [Akademischer Betreuer] [Siegesmund i Edward R. [Akademischer Betreuer] Sobel. "Structural and morphotectonic evolution of the Sierras Pampeanas (Argentina) constrained by a multithermochronometer approach / Stefan Löbens. Gutachter: Siegfried Siegesmund ; Edward R. Sobel. Betreuer: Siegfried Siegesmund". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/104430667X/34.

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SILVA, Adriana Cassiano da. "Reconstrução quaternária da dinâmica geomorfológica a partir das análises dos depósitos do baixo curso do rio Capibaribe/PE". Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18747.

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A reconstrução quaternária da evolução do baixo curso do rio Capibaribe está baseada em abordagens geomorfológicas, morfométricas e morfotectônicas, associados ao uso das geotecnologias, bem como na aplicação da abordagem relativa à tectônica sedimentar no município de Paudalho-PE. O objetivo dessa pesquisa é caracterizar a dinâmica fluvial a partir da investigação dos corpos sedimentares, que configuram elementos marcadores da paisagem, para entender os processos deposicionais da área e esclarecer a relação entre tectônica e o cenário estabelecido na drenagem, uma vez que, essa modalidade de pesquisa traz novas respostas para a compreensão da evolução recente da região. Para tanto, as amostras de sedimentos deformados foram coletadas em seis perfis e subdivididas em 30 “janelas” em depósitos de conglomerados e de linhas de pedras, sendo, após isso, submetidas às análises granulométricas, morfoscópicas e de difratometria de raios-X. Assim, a compilação dos mapeamentos de detalhe e analises sedimentológicas propiciaram uma modelagem mais precisa da área investigada. Os resultados permitiram evidenciar os seguintes fatos: o curso fluvial foi submetido a distintos graus de controle estrutural em escala regional, com a presença da captura do rio em uma direção de falha e brusca inflexão para o sul, trechos anômalos da drenagem e mudança em sua hierarquia; a análise morfotectônica permitiu constatar que as feições de knick-points, inselbergues, vales e cristas estão possivelmente sob o comando estrutural tectônico; os depósitos de conglomerados e de linhas de pedras apresentaram origem sedimentar alóctone, sendo o primeiro, com características fluviais, onde os grãos apresentam imaturidade textural, são pobremente selecionados, com padrão polido e translúcido, contendo seixos rolados e no segundo o aspecto principal é a evidência de clima mais seco. Esses depósitos sugerem interferência de controle estrutural e oscilação paleoclimática no seu arranjo deposicional e na distribuição espacial. Logo, as coberturas sedimentares e as feições morfotectônicas foram originadas em eventos distintos de basculamentos comandando a rede de drenagem e seu nível de base, assim como, a deposição dos depósitos, o que faz deduzir que o forte controle na estrutura física do relevo sugere reconfiguração tectônica.
Quaternary reconstruction of the evolution of the lower course of the Capibaribe river is based on geomorphological, morphometric and morphotectonic approaches associated with the use of geotechnology, and the implementation of the approach to sedimentary tectonics in Paudalho-PE municipality. The objective of this research is to characterize the fluvial dynamics from the investigation of sedimentary bodies that shape the landscape marker elements to understand the depositional processes of the area and clarify the relationship between tectonics and the scenery established in the drainage, since this modality research brings new answers for understanding the recent evolution in the region. Therefore, samples of deformed sediments were collected in six profiles and subdivided into 30 "windows" in deposits of conglomerates and stone lines, and after that, subjected to morphoscopic, granulometric and X-ray diffractometry analysis. Thus, the compilation of detailed mappings and sedimentological analysis provided a more accurate modeling of the investigated area. The results have highlighted the following facts: the fluvial course has been subjected to different degrees of structural control on a regional scale, with the presence of the river capture in one failure direction and sharp inflection to South, anomalous drainage passages and change in their hierarchy; morphotectonic analysis has allowed that the features of knick-points, inselbergs, valleys and ridges are possibly under the tectonic structural command; deposits of conglomerates and stones lines showed allochthonous sedimentary origin, the first with fluvial features, where the grains have not textural maturity, being poorly selected, with polished and translucent standard, containing pebbles and the second main aspect is the evidence of drier climate.These deposits suggest interference of structural control and paleoclimatic fluctuation in their depositional arrangement and spatial distribution. Thus, the sedimentary cover and the morphotectonic features have been originated in different events of tiltings commanding the drainage system and its base level, as well as the deposition of deposits, which makes deduce that the strong control of the physical relief structure suggests reconfiguration tectonics.

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Pinheiro, Marcos Roberto. "Estudo morfotectônico da região da serra de São Pedro e do baixo Piracicaba/SP". Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-11052015-170604/.

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As cuestas são definidas como uma forma de relevo dissimétrico, composta por uma vertente em declive íngreme de um lado e uma rampa em declive suave no reverso, decorrente da erosão diferencial das rochas. A região da Serra de São Pedro/SP, área de ocorrência de basaltos juro-cretáceos (topo da escarpa) e arenitos eólicos (escarpa e glacis) do Triássico ao Cretáceo Médio, consiste em uma das zonas mais típicas das cuestas na Bacia do Paraná, porém a configuração geometrizada do relevo da área, do sistema fluvial e até do baixo rio Piracicaba sugerem um controle tectônico das formas. Nesse sentido, o objetivo deste trabalho foi verificar o possível controle tectônico no relevo da Serra de São Pedro e do Baixo Piracicaba, focalizando a ação da Neotectônica, tendo como hipótese a existência de um forte controle das estruturas modernas sobre as formas. Os resultados mostraram que a atividade neotectônica na área é caracterizada principalmente pela atividade de falhas transcorrentes e normais subverticais WNW-ESE, W-E, NW-SE e NE-SW, ambas de pequeno rejeito e de impacto reduzido na morfologia do relevo. A influência das estruturas nas formas é mais intensa no sistema fluvial, comandando a dissecação do relevo de toda a área a partir de linhas estruturais que correspondem aos planos de juntas, grandes fraturamentos e falhas, ainda que a tectônica recente seja responsável pelo controle da direção apenas dos canais de 1º e 2º ordens. A Neotectônica condiciona ainda a formação de facetas triangulares na frente da escarpa da Serra de São Pedro, provoca perturbações de depósitos fluviais quaternários, anomalias no perfil longitudinal dos rios e inflexões dos interflúvios e canais de drenagem, além de pequenos basculamentos de blocos que causam a formação e degradação de terraços fluviais nos afluentes da margem direita do baixo Piracicaba. Essas informações são coerentes com os dados das estruturas medidas e materiais descritos em campo, bem como com as informações do contorno estrutural e dados geofísicos da área. Apesar do claro registro de neotectônica na região da Serra de São Pedro e do Baixo Piracicaba, os resultados demonstraram que a magnitude dessa atividade é reduzida e o seu impacto no relevo é pequeno, sendo que a configuração geomorfológica atual é mais influenciada por fatores litológicos, pela disposição das camadas sedimentares das rochas, pelos (paleo)climas e pela orientação/distribuição de estruturas tectônicas anteriores ao Neógeno, refutando assim a hipótese inicial do trabalho.
Cuestas are asymmetric landforms characterized by a steep slope along the plateau front and a gentle slope on its reverse, and they are interpreted as a relief formed by differential erosion of rocks. The São Pedro Ridge (Serra de São Pedro)/SP region, area with occurrence of juro-cretacic basalts (top of the ridge) and Triassic medium Cretaceous aeolian sandstone (scarp and glacis), is one of the most typical examples of the cuestas in the Paraná Basin. Although São Pedro Ridge is considered a cuesta, the geomorphological settings and the fluvial system (including the Lower Piracicaba River) of the area suggest a tectonic control on the landforms. Thus, the aim of this research was to verify a possible tectonic control on the São Pedro Ridge and Lower Piracicaba River landforms, emphasizing the Neotectonic influence. The hypothesis is that modern tectonics has a strong influence in the actual landforms. The results showed that the neotectonic activity in the study area is characterized mainly by sub-vertical strike-slip and normal faults WNW-ESE, WE, NW-SE and NE-SW, both with very small offsets and inconspicuous impact in the relief. The influence of the tectonic activity in the landforms is more intense in the fluvial system, controlling the relief dissection from joint planes, large fractures and faults, though modern tectonics is responsible for the control of the direction only of first and second order drainage channels. Neotectonics also controls the formation of triangular facets at the escarpment front of the São Pedro Ridge, faulting in quaternary fluvial deposits, anomalies in the longitudinal profiles of streams and changes in the direction of ridge lines and watercourses (river bends), as well as small block tilting which influences the formation and degradation of fluvial terraces of the Piracicaba right margin tributaries. These interpretations are coherent with the data set concerning the structures measured and materials characterized in the field, as well as with the information about the structural contour and geophysical data of the area. Despite the clear record of neotectonics in the São Pedro Ridge and Lower Piracicaba River region, the results demonstrated that the magnitude of the modern tectonic activity is small, and that the actual geomorphological configuration is more influenced by lithological factors, paleoclimates and the arrangement of sedimentary rock layers and pre-Neogene tectonic structures, thus refuting the initial hypothesis of this study.

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Santana, Rolando Gonz?lez. "Modelagem da salinidade do estu?rio do Serinha?m, Bahia - Brasil". Universidade Estadual de Feira de Santana, 2016. http://localhost:8080/tede/handle/tede/553.

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The Serinha?m estuary is located in the south of Bahia state, about 110km from Salvador, within the limits of the Ituber? municipality, between parallels 13 ? 30 'and 14 ? 00' South latitude and meridians 38 ? 50 ' and 39 ? 40 'West longitude, ending up in the Camamu Bay. It is located on the coastal part of the Environmental Protection Area (APA acronym in portuguese) of Pratigi inside the Ecopolo III. Exist in this area a low level of development of human activities, compared with other estuaries from Brazil and over the world. At the same time, it was found a lack of environmental studies, such as salinity and tidal estuary. In this work we studied the behavior of salinity in the estuary of Serinha?m, starting from the understanding of salt exchange process between the river and the sea. The study was approached from a systemic point of view, considering the different components of physical and geographical environment, hydrology, climate, morphology, oceanography, etc., in the regional and local context in which it is inserted. It was divided into three stages; first a literature review and survey of initial data, following later by collection of salinity and tidal data during five campaigns occurred in April, July and December 2014, August and September 2015. The salinity?s samples were collected at 137 stations along the estuary, with an optical refractometer and a multiparameter device Hanna. The tide stations were placed on the docks of Ituber? and Barra Serinha?m ports, using first two rules of tide and in the second measurement, three prototypes of autonomous automatic ultrasonic digital tide gauges, constructed and electronically calibrated in the lab. Finally, we done the office works, where the results of data collected were processed and represented in a GIS environment. It was concluded that there is a difference in salinity? seasonal behavior of the estuary, and that the presence of extreme events such as "El Ni?o" and "La Ni?a" can influence the behavior of salinity. Four elements rules the salinity of the estuary, the morphotectonic that controls the relief of the bottom; the tributaries; the tide and rainfall. The tides were classified as microtidal in December 2014 and August 2015; and as mesotidal in September 2015, due to the influence of syzygy tides during the spring equinox. The estuary was classified according to the salinity as positive; according to the flow rate, as thoroughly mixed and by the movement patterns as well blended or vertically homogeneous. These results are expected to contribute to future updates of the management plans of APA-Pratigi.
O estu?rio de Serinha?m est? situado no baixo sul do estado da Bahia, aproximadamente a 110Km de Salvador, dentro dos limites do munic?pio de Ituber?, entre os paralelos 13?30' e 14?00' de latitude Sul e meridianos 38?50' e 39?40' de longitude Oeste, desembocando na Ba?a de Camamu. Encontra-se na parte costeira da ?rea de Prote??o Ambiental (APA) do Pratigi, dentro do Ec?polo III. Nesta zona existe um baixo n?vel de desenvolvimento das atividades antr?picas em compara??o com outros estu?rios, do Brasil e do mundo. Ao mesmo tempo foi constatada a escassez de estudos ambientais, como salinidade e mar? do estu?rio. Neste trabalho estudou-se o comportamento da salinidade no estu?riodo Serinha?m, a partir da compreens?o do processo de interc?mbio salino entre o rio e o mar. O estudo foi abordado do ponto de vista sist?mico, considerando os diferentes componentes do meio f?sico-geogr?fico, hidrografia, clima, morfologia, oceanografia, etc., no contexto regional e local onde est? inserido. Foi dividido em tr?s etapas, primeiramente a revis?o bibliogr?fica e levantamento de dados iniciais, posteriormente foi realizada coleta de dados de salinidade e mar?, em cinco campanhas nos meses de abril, julho e dezembro de 2014, agosto e setembro de 2015. As amostras de salinidade foram coletadas em 137 esta??es ao longo do estu?rio, com um Refract?metro ?tico e um aparelho multipar?metroHanna. As esta??es de mar? foram colocadas nos Cais dos Portos de Ituber? e da Barra do Serinha?m, utilizando primeiramente dois r?guas de mar? e na segunda medi??o, 3 prot?tipos de mare?grafos digitais ultrass?nicos autom?ticos aut?nomos, constru?dos e calibrados eletronicamente no laborat?rio. Por ?ltimo os trabalhos de gabinete, onde foram processados os resultados das coletas de dados e espaceados num ambiente SIG. Foi poss?vel concluir que existe uma diferen?a no comportamento sazonal da salinidade do estu?rio, a presen?a de eventos extremos como ?El Ni?o? e ?La Ni?a? podem condicionar o comportamento da salinidade. Quatro elementos controlam a salinidade do estu?rio, a morfotect?nica que controla o relevo de fundo; os rios afluentes; a mar? e as precipita??es. As mar?s foram classificadas como micromar?s em dezembro de 2014 e agosto de 2015, e setembro de 2015 como mesomar?, pela influ?ncia das mar?s de siz?gia equinociais de primavera. O estu?rio foi classificado segundo a salinidade como positivo; segundo a taxa de fluxo, como totalmente misturado e pelos padr?es de circula??o comobem misturado ou verticalmente homog?neo. Com esses resultados, espera-se contribuir para as futuras atualiza??es dos planos de manejo da APA-Pratigi.

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Moura, Thaiane Campos. "Morfotectônica na bacia do Rio Preto (MG/RJ): influências da neotecônica na dinâmica e evolução da paisagem". Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/5364.

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A presente dissertação se propôs à investigar as implicações da morfotectônica na organização da paisagem na bacia hidrográfica do Rio Preto (RJ/MG), cuja localização corrobora para a análise de feições morfotectônicas entre duas unidades geomorfológicas do sudeste brasileiro, o Alinhamento de Cristas do Paraíba do Sul e o Planalto do Itatiaia. Diante dos objetivos traçados foram selecionadas técnicas morfométricas de aplicação sobre o relevo e a drenagem, representações cartográficas e incursões a campo, que conjuntamente à Fisiologia da Paisagem, em seus três níveis de abordagem, ampararam o entendimento sobre a o quadro morfoestrutural e morfotectônico presente no recorte espacial selecionado. As feições registradas em campo e os resultados coletados em laboratório apontam conjuntamente para a atividade neotectônica concomitante à dinâmica superficial da paisagem comum em regiões tropicais, que muitas vezes mascara feições de uma tectônica passiva sobre a paisagem. Resultados concretos alcançados revelam a neotectônica atualmente no Sudeste brasileiro, corroborando para feições paisagísticas morfotectônicas.
This dissertation proposes to investigate the implications of dynamic neotectonic in the organization of the landscape in Rio Preto basin (RJ/MG), whose location supports for analyzing morphotectonic features between two geomorphological units of southeastern Brazil, the Alinhamento de Cristas do Paraíba do Sul and the Planalto do Itatiaia. Before the objectives were selected for morphometric techniques application on the topography and drainage, cartographic representations and raids the countryside, which jointly to the physiology of the landscape, in its three levels of approach, bolstered the understanding about the dynamics showed this in the space selected clipping. The features recorded in the field and the results collected in laboratory point together to neotectonic activity concomitant to the superficial common landscape dynamics in tropical regions, which often masks a passive tectonic features on the landscape, but in many of the results it was possible to show that the study area is located in a dynamic tectonic framework.

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Zakerinejad, Reza [Verfasser], i Volker [Akademischer Betreuer] Hochschild. "Integrated Assessment of Gully Erosion Processes, Using Multispectral Remote Sensing, Stochastic Modelling, and GIS-based Morphotectonic Analysis; A Case Study in the Southwest of Iran / Reza Zakerinejad ; Betreuer: Volker Hochschild". Tübingen : Universitätsbibliothek Tübingen, 2016. http://d-nb.info/1163665126/34.

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PATRICELLI, GIULIA. "CARATTERIZZAZIONE SISMOTETTONICA DELL'AREA DI GIUNZIONE TRA IL SUDALPINO E LE DINARIDI (NE ITALIA)". Doctoral thesis, Università degli Studi di Trieste, 2021. http://hdl.handle.net/11368/2997279.

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L’attività tettonica recente del Friuli orientale è stata indagata tramite un approccio multidisciplinare. L’ara di studio, che comprende la Pianura Friulana orientale e il bordo Prealpino Giulio, rappresenta la zona di giunzione tra i fronti SSE vergenti della Catena Sudalpina e le strutture trascorrenti destre NW-SE del Friuli orientale e Slovenia occidentale. Attualmente, sia i dati GPS che sismologici mostrano che la deformazione che si accumula ad una velocità di 2-3 mm/a viene rilasciata dall’interazione tra faglie inverse e trascorrenti. Riguardo la sismicità, la distribuzione dei terremoti mostra che gran parte degli eventi è localizzata lungo l’arco alpino e prealpino e che almeno due terremoti forti (M>6) hanno colpito l’area di studio: il terremoto del 1511 (Mw 6.3) e la sequenza del 1976-1977 (Mw<6.4). Di recente, l’attivazione della Faglia di Raune ha causato due sequenze sismiche, nel 1998 (Mw 5.6) e nel 2004 (Mw 5.2). Con lo scopo di approfondire il ruolo delle faglie attive del Friuli orientale nella sismicità regionale, questo lavoro è focalizzato all’attività recente delle strutture tettoniche. Seguendo un approccio multidisciplinare, la geometria 3D di 4 sistemi di faglia è stata ricostruita tramite l’interpretazione di linee sismiche ENI combinata con l’analisi della distribuzione ipocentrale dei terremoti. Successivamente, è stata effettuata l’analisi morfotettonica nella porzione settentrionale dell’area di studio con lo scopo di individuare le anomalie superficiali relative all’attività tettonica. I dati morfotettonici raccolti hanno permesso di definire una zona di deformazione ad orientazione NW-SE, che evidenzia l’attività recente del Thrust di Colle Villano-N (CV-N) e del Sistema di Faglie transpressivo Colle Villano – Borgo Faris Cividale (CV-BFC). Sulla base dei risultati morfotettonici, sono state realizzate due trincee paleosismologiche: la trincea di Fraelacco attraverso il Thrust CV-N e la trincea di Campeglio sullo splay CV. Il sito di Campeglio ha messo in evidenza strutture di paleoliquefazione, suggerendo che l’area ha subito scuotimento. Diversamente, nella trincea di Fraelacco la dislocazione del Subsintema di Canodusso (21 – 23 ka) ha permesso di individuare due eventi deformativi negli ultimi 21 ka, con il più recente che si è probabilmente verificato in tempi storici.
The recent tectonic activity of eastern Friuli was investigated through a multidisciplinary approach. The study area, which comprises eastern Friuli Plain and the Julian prealpine border, represents the junction zone between the SSE verging front of the Southalpine Chain and the NW-SE trending strike slip structures of the eastern Friuli-western Slovenia domain. At present, both seismological and GPS data show that the 2-3 mm/yr accumulating deformation is released through the interaction among reverse, transpressive and strike-slip faults. Regarding seismicity, the distribution of earthquakes shows that most of the events are mostly located along the prealpine and alpine arcuate belt and at least two Mw > 6.0 events are documented: the 1511 Mw 6.3 earthquake and the 1976-77 sequence (Mw ≤ 6.4). In more recent times, the activation of the Raune strike-slip fault in western Slovenia caused the occurrence of two seismic sequences, in 1998 (Mw 5.6) and 2004 (Mw 5.2). With the aim to further explore the involvement of the active faults of eastern Friuli during the strongest seismic events occurred in the area, this work is focused on the recent activity of the tectonic structures. Following a multidisciplinary approach, the deep 3D-geometry of 4 main fault-systems were reconstructed by combining ENI seismic lines interpretation and hypocentral distribution analysis. Successively, a morphotectonic survey was conducted along the Julian prealpine border with the aim to detect the surficial anomalies related to tectonic activity. The collected morphotectonic hints allowed to define a NW-SE elongated zone of surficial deformation, highlighting the recent activity of the Colle Villano-N Thrust (CV-N) and the Colle Villano-Borgo Faris-Cividale trasnpressive Fault-System (CV-BFC). Based on the morphostructural results, two paleoseismological trenches were dug: the Fraelacco trench across the CV-N Thrust and the Campeglio trench across the CV Thrust. At Campeglio site, the excavated trench revealed the presence of paleoliquefaction features, thus suggesting that the area experienced seismic shaking. Differently, at Fraelacco site, the displacement of the Canodusso Subsynthem (21- 23 ka cal BP) allowed to identify two deformative episodes in the last 21 ka, with the latest likely occurred in historical times.

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Dyriw, Nicholas J. "Tectono-magmatic setting of Seafloor massive Sulfide systems: Investigating Solwara 1 Cu-Au deposit". Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/207956/2/Nicholas_Dyriw_Thesis.pdf.

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This thesis investigates the tectonic and magmatic setting of a Copper-rich seafloor massive sulfide deposit. Integrated multi-scale data analysis produced a regional to deposit-scale framework to constrain how, why and where these types of mineral deposits form. Outcomes from this research advance our understanding of 1) regional tectonic evolution of the East Manus Basin, and 2) volcanic and magmatic processes conducive to seafloor massive sulfide deposit formation.

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Pousse, Léa. "Aléa sismique le long des grands décrochements vénézuéliens". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAU049/document.

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Le Venezuela est traversé par une zone de limite de plaque. Ce système tectonique accommode les mouvements relatifs de trois plaques majeures: la plaque Sud-Américaine, la plaque Caraïbe et la plaque de Nazca. Ce système est constitué de failles décrochantes actives qui ont généré au Venezuela de nombreux séismes de magnitude supérieure à 6-7. Parmi ces failles, cette thèse se focalise sur la faille de Boconó et la faille d’El Pilar.Le but de cette thèse est d'étudier l'activité de ces failles sur plusieurs échelles de temps en utilisant une approche multidisciplinaire qui combine analyses morphotectonique, paléosismologique et géodésique. Cette approche a permis de préciser le régime de déformation de ces failles indispensable à l'estimation de l'aléa sismique.Antérieurement à cette thèse, dans la région de Yaracuy, l’activité tectonique du segment nord de la faille de Boconó était mal contrainte faute de données géodésiques ou géochronologiques suffisantes. Or cette partie de la faille a provoqué en 1812 un séisme de Mwi 7.4 qui a détruit les villes de la région.Grâce à la datation par Béryllium-10 de la surface d’exposition de cônes alluviaux décalés par la cinématique dextre de la faille, cette thèse montre que la vitesse quaternaire de la faille est comprise entre 5.0 et 11.2 mm/an.En comparant cette vitesse estimée sur ~ 200 ka et le taux de glissement estimé en champ lointain par des mesures géodésiques (~ 12 mm/an), il peut être proposé que la faille de Boconó accommode une grande partie de l'extrusion du Bloc Nord Andin. La réalisation de carte de vitesses moyennes de déformation à partir d'images SAR a montré l'absence de glissement asismique le long de la faille de Boconó entre 2007 et 2011. En extrapolant ce comportement aux derniers 200 ans, il en résulte que, depuis le dernier séisme en 1812 il y a une accumulation de déficit de glissement de quelques mètres selon la vitesse de glissement considérée. Cette faille représente donc un aléa sismique important pour la région. Une tranchée réalisée pour préciser cet aléa a montré que trois évènements sismiques de Mw > 6-6.5 ont lieu depuis 1300 ap. J.-C., le dernier de ces événements étant probablement le séisme historique de 1812.Au Nord Est du Venezuela, la faille d’El Pilar accommode l’intégralité du mouvement relatif entre la plaque Sud-Américaine et la plaque Caraïbe (~ 20 mm/an). Après le séisme de Ms 6.8 en 1997, le segment émergé de cette faille a subit un important « afterslip ». Des mesures géodésique réalisées en 2003, 2005 et 2013 ont montré que ce segment glisse encore asismiquement (~12 – 13 mm/an). Cette thèse présente une carte des vitesses de déformation entre 2007 et 2011 calculée par interférométrie radar. Celle-ci a permis de montrer que cette faille glisse asismiquement de façon non uniforme dans l’espace et le temps. L’analyse en série temporelle des déplacements a révélé que le glissement asismique de certains tronçons de la faille subit une accélération en Juin 2009 avec des vitesses de glissement asismiques supérieures au déplacement relatif entre les plaques. Cette observation permet d’interpréter que le glissement asismique a un comportement transitoire, en effet, des périodes de blocage et des périodes de larges glissements se succèdent. Cette succession doit probablement se poursuivre tout le long de la période intersismique comme le suggèrent le faible nombre de séismes historiques et préhistoriques au regard de la vitesse de coulissage le long de la faille. Enfin ce glissement asismique présentant des variations spatiales et temporelles est probablement contrôlé par la présence de serpentinites et d’une activité hydrothermale le long de la zone de faille, contexte connu pour favoriser des comportements rhéologiques de ce type
Venezuela is crosscut by a plate boundary zone, this tectonic setting accommodates the relative displacements of three plates: the South America, the Caribbean and the Nazca Plate. This tectonic system is constituted of active strike-slip faults which have provoked several events of Mw > 6-7. Among these faults, this thesis focuses on the Boconó Fault and on the El Pilar Fault.The aim of this dissertation is to study fault activities on several time scales using a multidisciplinary approach. This approach, which combines morphotectonic, paleoseismologic and geodetic analyses, leads to clarify the deformation pattern. This knowledge is essential to the seismic hazard assessment.Previously to this thesis, in the Yaracuy valley, the tectonic activity of the Boconó fault was poorly constrained due to the lack of geodetic and geochronological data; although a part of this fault triggered in 1812 an earthquake of Mwi 7.4. Through 10-Beryllium surface exposition dating of two alluvial fans shifted by the fault, this thesis shows that the Quaternary slip rate of the fault ranges from 5.0 to 11.2 mm/yr. By comparing this rate estimated on ~ 200 ka with the slip rate estimated in far field with geodesy (~ 12 mm/yr), it can be proposed that the Boconó fault accommodates a major part of the North Andean Block extrusion. Velocity map of ground displacements calculated using SAR images shows the lack of aseismic slip along the Boconó Fault during the 2007-2011 period. The extrapolation of this locked activity since the 1812 event, implies that there is a slip deficit of several meters. Therefore, the Boconó Fault have to be taken into account in the regional seismic hazard assessment. A paleoseismological trench across the studied segment is also presented in this thesis in order to constrain this assessment. Three events of Mw > 6 - 6.5 have been recorded in this trench since 1300 CE, the last of these events is probably the 1812 historical earthquake.In the north-western region of Venezuela, the El Pilar Fault accommodates the whole relative displacement between South-America and Caribbean Plates (~ 20 mm/yr). After the last event in 1997 (Ms 6.8) the on-shore segment of this fault undergoes an important afterslip. Geodetic campaign measurements performed in 2003, 2005 and 2013 showed that this segment was still creeping (~ 12 - 13 mm/yr). This thesis presents an InSAR analysis performed with 18 SAR images spanning the 2007-2011 period. The velocity map shows that the aseismic slip is not uniform along the El Pilar Fault. Time-series analysis reveals locally a creep acceleration. This transient is characterised by a rate exceeding the rate of surrounding plate motion. Therefore, the El Pilar fault seems to be partially locked during several years and then undergoes transient creep during several months. This succession should last during the whole interseismic period as suggested by the low seismic activity and paleoseismological trenches. This creep showing spatio-temporal variations is probably controlled by the existence of serpentinites lenses and the hydrothermal activity, which are known to promote this kind of rheological behaviour

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Kurtz, Robin. "Évolution spatio-temporelle des déformations sismiques tardi-Pleistocènes et Holocènes dans le massif du Gobi-Altaï, Mongolie : approches morphotectonique et paléosismologique". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT141/document.

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La Mongolie occidentale a connu une sismicité intracontinentale exceptionnelle au cours de la première moitié du XXe siècle, avec 4 évènements sismiques d'une magnitude supérieure à 7.9, localisés sur des grandes structures décrochantes en régime transpressif senestre. Cette sismicité historique a été qualifiée d’essaim sismique, et des études paléosismologiques indiquent que ce phénomène a déjà pu se produire par le passé (3 à 4 ka). Mais si la partie est de la chaine du Gobi-Altaï a rompu lors du séisme du même nom en 1957 (Mw8) le long de la faille de Bogd orientale (WBF), plusieurs traces de failles affectant des formations Holocènes et présentant des longueurs > 100 km ont été documentées dans la partie ouest du massif, sans pour autant faire l’objet d’études quantitatives.Cette thèse apporte un état des lieux de l’activité sismique dans le Gobi-Altaï, au travers d’une cartographie détaillée des escarpements de failles actives au cours du pléistocène supérieur, associée à une analyse de la segmentation au regard de critères géométriques et cinématiques. Parallèlement, des investigations morphotectoniques et paléosismologiques, couplées à des méthodes de datations au 10Be in situ, OSL et 14C, ont permis de quantifier les vitesses de glissement depuis le Pléistocène supérieur, et les âges des paléo-ruptures au cours de l’Holocène sur les deux principaux décrochements analysés : les failles de la Vallée des Lacs (VOLF), et de Bogd occidentale (WBF) ; des données préliminaires permettent également de contraindre l’âge de la dernière rupture et la vitesse de glissement sur les failles de Tsogt (TF) et de Tsagaan Gol (TGF), situées respectivement dans le prolongement occidental de la WBF et de la VOLF. De plus, des mesures systématiques des décalages cosismiques horizontaux enregistrés par la morphologie, notamment le long de la rupture de surface du séisme de 1957, couplés à l’utilisation et le développement d’une approche statistique de détermination des glissements cosismiques moyens au regard de la segmentation, a permis de déterminer la fonction de distribution du glissement le long de l’EBF sur 3 cycles sismiques, suggérant d’une part une distribution du glissement assez homogène le long de la rupture, et d’autre part que le glissement du séisme généré en 1957 est d’une amplitude comparable de celle des précédents séismes, pour au moins 50 % de la rupture principale. Cette approche de détermination statistique des glissements moyens sur plusieurs cycles sismiques est prometteuse mais présente néanmoins certaines incohérences, et des voies de développement et de validations sont proposées.Les paramètres morphotectoniques et les âges des paléoséismes documentés dans cette thèse présentent une grande cohérence avec les données précédemment acquises sur l’EBF, avec des vitesses de faille lentes (0,7 ± 0,2 mm.a-1 sur la WBF et 0,5 ± 0,1 mm.a-1 sur la VOLF), des périodes de retour longues (4,0 ± 1,2 ka pour la WBF), et des décalages cosismiques relativement importants (2 – 4 m). Nos mesures de vitesses de faille indiquent par ailleurs une distribution de la déformation depuis la EBF vers les WBF et VOLF, séparant la déformation en deux faisceaux de failles, l’un se branchant au nord depuis la VOLF sur la TGF. Les déterminations des âges de paléoséismes indiquent une possibilité de cluster entre les différentes failles étudiées, avec trois ruptures potentiellement synchrones au cours de l’Holocène, dont une, rompant l’intégralité des décrochements analysés (WBF, EBF et VOLF), s’avère être temporellement corrélée au précédent cluster potentiellement identifié à 3 – 4 ka. Les paramètres présentés dans cette thèse permettent finalement de calculer des paléomagnitudes associées aux deniers évènements sur les WBF et VOLF, comprises entre Mw7,6 et Mw8 selon les paramètres et les lois considérés. Ces données fondamentales pourront servir de canevas de base pour les actuelles études d’aléas sismique en Mongolie
Western Mongolia experienced an exceptional intracontinental seismic activity during the first part of the XXth century, with four seismic events with Mw > 7.9, located on large strike-slip faults with a transpressive left-lateral motion. This historical seismicity has been qualified as a cluster, and paleoseismological studies indicate that this phenomenon might have occurred 3 to 4 ka ago. Although the eastern part of the Gobi-Altai mountain range broke during the eponymous earthquake in 1957 (Mw8) along the Eastern Bogd Fault (EBF), several fault traces affecting Holocene formations and presenting continuous fault length > 100 km have been documented on the western part of the range, while not been the purpose of quantitative studies.This thesis first gives an inventory of the seismic activity within the Gobi-Altai, through detailed mapping of the fault scarps which show activity during the late-Pleistocene, also with an analyze of the fault segmentation regarding to geometric and kinematic criteria. Secondly, some morphotectonical and paleoseismological surveys have been carried on, along with dating techniques as 10Be in situ, OSL and radiocarbon, which allow quantifying the faults slip-rates since late-Pleistocene, and paleo-ruptures ages during the Holocene period on the two main strike slip faults analyzed : the Valley of Lakes Fault (VOLF), and the Western Bogd Fault (WBF); preliminary data also allow quantifying the slip rates and the age of the most recent event along the Tsogt Fault (TF) and the Tsagaan Gol fault (TGF), respectively located in the westward continuation of the WBF and the VOLF. Moreover, systematic lateral offset measurements have been carried on along the faults traces, and especially along the 1957 surface rupture, where a statistical approach based on probability density has been applied in order to assess the average lateral offsets successively recorded by the landforms, and reveals that the slip distribution along the EBF on 3 seismic cycles. This suggests first that the slip distributions rather even along the rupture, and secondly that the slip related to the 1957 earthquake is of the same amount than previous major ruptures on that fault, for half of the main 1957 surface rupture. This approach of average coseismic slip assessment on several seismic cycles is promising, but still presents some inconsistencies, and we propose developments and validation perspectives.Morphotectonic parameters and ages of paleo-earthquakes reported in this thesis present a strong consistency with former studies along the EBF, with slow slip-rates (0,7 ± 0,2 mm.yr-1 on the WBF and 0,5 ± 0,1 mm.yr-1 on the VOLF), and significant left lateral coseismic offsets (2 – 4 m). Our measurements of slip rates indicate furthermore a distribution of the on-fault deformation from the EBF to the WBF and the VOLF, splitting the deformation in two branches, the north one reaching the TGF and the southern one visibly branches on the TF. Assessments of the paleoearthquakes ages show three possible clusters between the studied faults during the Holocene time, and one of them may break the three faults (WBF, EBF and VOLF), and seems as well to correspond to the cluster possibly identified 3-4 kyr ago. The fault parameters presented in this thesis allow computing the paleomagnitudes related to last seismic events along the WBF and the VOLF, ranging from Mw7.6 and Mw8, depending of parameters and empirical relations considered. Finally those fundamental data may serve as basic pattern for current seismic hazard assessments in Mongolia

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Lima, Meire Mateus de [UNESP]. "Estudo do meio físico e caracterização da capacidade de suporte natural da região de Pirassununga/SP". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/139477.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Os crescentes usos e ocupação do meio e utilização dos recursos naturais têm mostrado a necessidade do desenvolvimento de estudos integrados dirigidos a uma adequação das atividades do homem com a capacidade de suporte natural do meio físico. Desta forma, este projeto objetiva, para a região de Pirassununga, localizada no centro-nordeste paulista, aplicar um procedimento metodológico que auxilie a compartimentação do meio físico, mediante o uso de geotecnologias e aspectos geodinâmicos, visando o planejamento do uso e ocupação da terra, com fins de definir a suscetibilidade natural à erosão e a capacidade de suporte natural do meio. Tais informações poderão ser utilizadas pelos produtores rurais e órgãos públicos no intuito de orientar a tomada de decisões quanto às medidas de controle para os problemas ambientais encontrados, para a recuperação de áreas impactadas, bem como orientações para o uso e ocupação sustentável da terra, reduzindo os impactos negativos. Com base nos resultados das análises de drenagem, do relevo, morfoestrutural, morfotectônica e da evolução paleoambiental (isobases confluentes) nota-se que a região apresenta uma grande densidade de drenagem, variação altimétrica e de classes de declividade, assim como um intenso fraturamento, o que gera paisagens de abatimento e soerguimento de blocos (horsts e grabens), altos e baixos estruturais deformados e altos e baixos topográficos intercalados, exigindo, deste modo, indicações de manejo específicos para cada área. A análise da evolução da paisagem, por meio das isobases confluentes, contribui ainda para melhor definir o fraturamento regional e o domínio de processos colúvio-aluvionares, formadores das associações de solos. A integração dos diversos temas desenvolvidos neste trabalho possibilitou a geração das cartas temáticas de suscetibilidade natural à erosão, indicação de áreas para preservação ambiental e áreas para destinação dos resíduos antrópicos, sólidos e líquidos, buscando a classificação mais adequada da capacidade de suporte natural da área. A partir dos resultados constatou-se que na região de Pirassununga predominam as suscetibilidades naturais à erosão baixas e moderadas, assim como uma alta capacidade de suporte natural, acompanhando as planícies de inundação atual/subatual e os planaltos muito baixos a médios. Merecendo atenção especial a porção leste da área, por apresentar capacidade de suporte predominantemente moderada e a porção oeste, por apresentar capacidades de suporte de moderadas a muito baixas, podendo ser utilizadas de forma restrita, requerendo, todavia, estudos mais específicos para melhor dirigir tal ocupação. Considerando ainda que, com a aplicação de técnicas inadequadas de uso, manejo do solo e disposição de resíduos, a suscetibilidade natural à erosão pode aumentar significativamente e, a capacidade de suporte natural do meio ambiente ficar comprometida. Desta forma, recomenda-se que os manejos, considerando as peculiaridades de cada local individualmente, sejam definidos em função das recomendações de profissionais capacitados em cada atividade, diminuindo assim os problemas para o uso e ocupação do meio físico da região.
The increasing use and occupation of the environment and utilization of the natural resources has presented the need for the development of integrated studies driven towards an adaptation of the activities performed by people with natural support for the physical environment. This way, this project has the objective, for a region of Pirassununga, located in the center northeast of São Paulo, to apply a methodological procedure that aids the partitioning of the physical environment, with the use of geotechnologies and geodynamic aspects, seeking the planning of the soil occupation use, to define the natural susceptibility to the erosions and the capacity of natural environment support. Such information can be utilized by farmers and public agencies in the intent orientate the decision making of the control measures for the environmental problems found, for the recovery of impacted areas, as well as in orientating for sustainable soil occupation use, reducing the negative impacts. With basis on the analysis results of drainage, relief, morphostructural, morphotectonic and the paleoenvironmental (confluent isobases), it is noticed that the region presents a great density of drainage , altimetry variation and gradient classes, as well as intense fracturing, which generates a landscape of abatement and uplift of blocks (horst and grabens), high and low structural deformation and high and low interleaved topographic, demanding, in this way, specific handling indications for each area. The landscape evolution analysis, by confluent isobases, contributes to better define the regional fracturing and the command of colluvium-alluvial processes, makers of the soil association. The integration of the various developed themes in this work enabled the creation of themed letters for natural susceptibility to erosions, indication of environmental preservation areas and areas for anthropic residue destination, solid and liquid, seeking the more adequate classification of the natural support of the capacity for the area. With the results, it was found that in the region of Pirassununga prevails the natural susceptibility to low and moderate erosions, as well as high capacity for natural support, following the current and not so current flood plains and the very low to medium plateaus. Deserving special attention to the east portion of the area for presenting support capacity mainly moderate and the west portion for presenting a moderate to very low support capacity, being able to be utilized in a restrict manner, requiring, however, more specific studies to better drive such occupation. Considering that, with the application of inadequate techniques of use, soil handling and residue disposal, the natural susceptibility to erosions can increase significantly and the natural support capacity of the environment can become compromised. This way, it is recommended that handling, considering the peculiarities of each individual location, be defined due to recommendation of capacitated professionals in each activity, thus decreasing the problems for the use and occupation of the physical environment of the region.

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Bense, Frithjof A. Verfasser], Siegfried [Akademischer Betreuer] [Siegesmund, Georg [Akademischer Betreuer] Grathoff i Alfons [Akademischer Betreuer] Berger. "Multi-Method Chronometric Constraints on the Thermal, Structural and Morphotectonic Evolution of the Eastern and Western Sierras Pampeanas with Special Emphasis on K-Ar Dating of Fault Gouges / Frithjof A. Bense. Gutachter: Siegfried Siegesmund ; Georg Grathoff ; Alfons Berger. Betreuer: Siegfried Siegesmund". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044739428/34.

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Nascimento, Mayara Aline Santos Ribeiro do [UNESP]. "Evolução geomorfológica e tectônica da porção norte da Bacia do Amazonas: região do Rio Apuaú (AM)". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/147102.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A paisagem na Amazônia tem mostrado um quadro geomorfológico evolutivo associado a condicionamentos tectônicos no controle da rede de drenagem, com importantes mudanças nos cursos dos rios associadas a sistemas de falhas no âmbito da Neotectônica. Esta pesquisa compreende o estudo da bacia hidrográfica do rio Apuaú, afluente da margem esquerda do rio Negro na sua porção média, a norte de Manaus, no Estado do Amazonas. Foi subsidiada por estudos estruturais e geomorfológicos apoiados em dados de campo, de sensores remotos e de datação dos depósitos aluvionares. Foram reconhecidos blocos desnivelados do relevo, com rupturas de declive (knickpoints) associadas e controladas por falhas. A rede de drenagem apresenta padrões anômalos dos cursos d’água, capturas, meandros e canais encurvados, alinhamento de canais retilíneos, marcando zonas de juntasou zonas de falhas. Os blocos controlam também a distribuição de terraços, paleoterraços e canais abandonados, e suas datações por LOE apontam para depósitos mais antigos na faixa de 53.000 a 62.200 anos, intermediários na faixa de 20.330 a 23.100 anos, e depósitos atuais. O quadro geológico-estrutural aponta para compartimentos morfotectônicos, controlados por falhas normais e falhas transcorrentes destrais associadas. As falhas normais condicionam blocos rotacionados, a rede de drenagem e a distribuição dos depósitos aluvionares, enquanto as falhas transcorrentes parecem balizar e controlar os blocos na porção norte e leste da bacia hidrográfica. Reconhecidas em campo, as falhas normais formam dois grandes conjuntos, orientados NE-SW a EW e NW-SE, enquanto as falhas transcorrentes destrais predominam com orientação próxima a EW e transcorrentes sinistrais NE-SW. O tratamento das populações de falhas para obtenção de eixos de paleotensões indica um evento distensivo NNW-SSE a NW-SE, interpretado como mais antigo, um evento distensivo NE-SW a EW, ao qual pode ser atribuído o ajuste dos blocos rotacionados, controlados por falhas NW-SE, e um arranjo compressivo NNW-SSE a NW-SE, responsável pelas falhas transcorrentes, ambos mais jovens. A associação entre as falhas transcorrentes destrais EW balizando os blocos abatidos e rotacionados controlados por falhas normais NW-SE promove o rearranjo da rede de drenagem e o ajuste da distribuição das coberturas superficiais, indicando atuação do regime neotectônico, decorrente da interação da Placa Sulamericana com a Placa do Caribe.
The landscape in the Amazon has shown a geomorphological evolution associated to tectonic constraints in controlling the drainage network, with important changes in the stream courses associated with fault systems within the scope of the neotectonic regime. This research comprises the study of the catchment of the Apuaú river, a tributary of the left bank of the Negro river in its middle portion, North of Manaus, in the state of Amazonas. Structural and geomorphological studies supported by field data, remote sensing and dating of alluvial deposits were carried out. Uneven relief blocks were recognized with associated slope ruptures (knickpoints) and controlled by faults. The drainage network has anomalous patterns of water courses, captures, meanders and curved channels, rectilinear alignment of channels, indicating fracture or fault zones. The blocks also control the distribution of terraces, paleoterraces and abandoned channels, and their LOE datings point to older deposits in the range 53,000 to 62,200 years, intermediate ones in the interval of 20,330 to 23,100 years and current deposits. The geological and structural framework points to morphotectonic compartments controlled by normal faults and associated dextral strike-slip faults. Normal fault constrain rotated blocks, drainage network and the distribution of alluvial deposits, while the strike-slip faults seem to delimit and control the blocks in the northern and eastern parts of the hydrographic basin. Recognized in the field, normal faults adjust into two large sets, oriented NE-SW to EW and NW-SE, while strike-slip faults predominate striking close to EW dextral and NE-SW sinistral ones. Fault population analysis to obtain paleostress axis indicates a NNW-SSE to NW-SE extensional event, interpreted as the oldest, followed by one NE-SW to EW distensive event, which can be attributed to the adjustment of rotated blocks, controlled by NW-SE faults, and a compressive arrangement NNW-SSE to NW-SE, responsible for the slip faults.The association between the EW dextral transcurrent faults controlling uneven and rotated blocks affected by NW-SE normal faults promotes the rearrangement of the drainage system and adjusting the distribution of surface covers, indicating actions of the neotectonic regime, due to the interaction of the South American Plate with the Caribbean Plate.

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Nascimento, Mayara Aline Santos Ribeiro do. "Evolução geomorfológica e tectônica da porção norte da Bacia do Amazonas : região do Rio Apuaú (AM) /". Rio Claro, 2016. http://hdl.handle.net/11449/147102.

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Orientador: Norberto Morales
Resumo: A paisagem na Amazônia tem mostrado um quadro geomorfológico evolutivo associado a condicionamentos tectônicos no controle da rede de drenagem, com importantes mudanças nos cursos dos rios associadas a sistemas de falhas no âmbito da Neotectônica. Esta pesquisa compreende o estudo da bacia hidrográfica do rio Apuaú, afluente da margem esquerda do rio Negro na sua porção média, a norte de Manaus, no Estado do Amazonas. Foi subsidiada por estudos estruturais e geomorfológicos apoiados em dados de campo, de sensores remotos e de datação dos depósitos aluvionares. Foram reconhecidos blocos desnivelados do relevo, com rupturas de declive (knickpoints) associadas e controladas por falhas. A rede de drenagem apresenta padrões anômalos dos cursos d’água, capturas, meandros e canais encurvados, alinhamento de canais retilíneos, marcando zonas de juntasou zonas de falhas. Os blocos controlam também a distribuição de terraços, paleoterraços e canais abandonados, e suas datações por LOE apontam para depósitos mais antigos na faixa de 53.000 a 62.200 anos, intermediários na faixa de 20.330 a 23.100 anos, e depósitos atuais. O quadro geológico-estrutural aponta para compartimentos morfotectônicos, controlados por falhas normais e falhas transcorrentes destrais associadas. As falhas normais condicionam blocos rotacionados, a rede de drenagem e a distribuição dos depósitos aluvionares, enquanto as falhas transcorrentes parecem balizar e controlar os blocos na porção norte e leste da bacia hi... (Resumo completo, clicar acesso eletrônico abaixo)
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Billant, Jérémy. "Caractérisation de la déformation tectonique récente du système de failles de Belledonne et de l'avant pays alpin (vallée du Rhône) : apports d'une approche pluridisciplinaire". Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4311/document.

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Le but de cette étude est de caractériser par une approche multi-disciplinaire les déformations tectoniques Plio-Quaternaire associées au système de failles de Belledonne (Alpes de l'Ouest).Ce système de faille est composé de plusieurs décrochements qui sont des Bauges au Vercors, la faille dextre NE-SW de l'Arcalod, la faille bordière de Belledonne, dextre et NE-SW, la faille sénestre NW-SE du Brion et la faille NE-SW dextre du Jasneuf.La détermination des états de contraintes tardi-Cénozoique montre que le champ de contrainte actuel responsable de la cinématique en décrochement le long du système de faille de Belledonne date de la fin du Pliocène supérieur/début du Pléistocène et a succédé au champ de contrainte causé par la collision alpine.Les failles de l'Arcalod et du Brion présentent des marqueurs morphologiques décalés mais ambiguës et d'âge incertain (probablement anté-Rissiens). La trace de la faille bordière de Belledonne n'a pu être déterminée, suggérant que la déformation associée à cette dernière soit accommodée dans une large bande de cisaillement.La faille du Jasneuf décale des morphologies d'âges supposés messiniens et anté-Rissiens. La vitesse de cette faille intégrée depuis le messinien serait de 0,13±0,03 mm/an. Considérant que cette faille est limitée à la couverture elle pourrait générer des séismes de magnitude 5,7 tous les ~500 ans.L’accommodation de la déformation actuelle dans l'avant-pays a été étudié dans la vallée de Toulaud (SW de Valence) où une faille tardi-hercynienne recoupe le canyon messinien du Rhône. Les premiers résultats indiquent que la faille décale verticalement le canyon, attestant d'une tectonique Plio-Quaternaire
The aim of this study is to characterize the Plio-Quaternary tectonic deformations related to the Belledonne fault system (western Alps). The low deformation rates and high erosion rates in the study area imply that a multi-disciplinary approach.From the Bauges to the Vercors massif this fault system is composed of strike-slip faults that are the NE trending right-lateral strike-slip Arcalod fault, the NE trending right-lateral strike-slip Belledonne border fault, the NW trending left-lateral strike-slip Brion fault and the NE trending right-lateral strike-slip Jasneuf fault.The determination of the late Cenozoic stress states revealed that the modern stress field responsible for the Belledonne fault system strike-slip kinematics dates from late upper Pliocene/early Pleistocene and came after the stress field caused by alpine collision.Unclear and undated (but probably pre Rissian) offset morphologic markers are described along the Arcalod and Brion faults. Belledonne border fault trace is not determined suggesting that deformation is accommodated in a wide shearing band.The Jasneuf fault offset morphologies whom ages are supposed Messinian and pre Rissian. Fault slip rate integrated since Messinian would be of 0.13±0.03 mm/yr. Considering that this fault appears limited to the sedimentary cover and excluding an aseismic behavior, she can generate 5.7 Mw earthquake each ~500 years.Modern deformation in the foreland is studied in the Toulaud valley (SW of Valence city) where a late Hercinian fault cross-cut the Messinian canyon of the Rhône river. First results show that the fault offset vertically the canyon, attesting aof Plio-Quaternary tectonics along it

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Farbod, Yassaman. "Active tectonics of the Doruneh Fault : seismogenic behavior and geodynamic role". Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4306/document.

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Ce travail de thèse porte sur la tectonique active du système de faille de Doruneh (DFS) situé au NE de l'Iran. Une approche combinée de géologie structurale, morpho-tectonique, géomorphologie quantitative et datation par des nucléides cosmogéniques 36Cl et 10Be nous a permis de décrire la cinématique ainsi que le rôle géodynamique du DFS dans le contexte de la collision Arabie-Eurasie.Le DFS comprend trois zones avec des caractéristiques structurales, géomorphologiques et cinématiques distinctes, (a) inverse-senestre pour la WFZ (Ouest) (b) purement senestre pour la CFZ (Centre) et (c) inverse pour l'EFZ (Est). Les âges d'abandon de trois générations de cônes alluviaux quaternaires ont été déterminés à ~12, ~36 et ~100 ka. Ces âges, combinés avec les décalages mesurés, indiquent une vitesse maximum de déplacement horizontal senestre de ~5,3 mm/an pour l'Holocène. Notre analyse d'aléa sismique indique que la longueur maximale d'un segment sismogène varie de 70 à 100 km, ce qui pourrait produire des séismes caractéristiques de magnitude 7.2 à 7.4 avec des intervalles de récurrence de ~750 ans.Nous proposons un nouveau modèle géodynamique dans lequel l'EFZ est impliquée dans une zone de cisaillement dextre d'orientation NNW entre Iran central et Eurasie. Le mouvement vers le nord de l'Iran central est accommodé dans cette zone de relais en transpression par du raccourcissement sur des failles inverses d'orientation NW, et transféré vers le Nord par des faille dextres d'orientation NNW
This study focuses on the active tectonics of the Doruneh Fault System (DFS) in the north-eastern part of central Iran. A combined approach of geological and morphotectonic mapping, fault kinematic analysis, as well as in situ-produced cosmogenic dating (36Cl and 10Be) allowed us to characterize the active kinematics and geodynamic role of the DFS in the context of the Arabia-Eurasia collision.The DFS comprises Western, Central and Eastern fault zones (WFZ, CFZ, EFZ) with distinct structural, geomorphic and kinematic characteristics. The WFZ is oblique reverse-left-lateral, the CFZ is pure left-lateral and the EFZ is reverse. Exposure ages of ~12, ~36 and ~100 ka have been determined for three generations of alluvial fan abandonment surfaces along the DFS. Combining geomorphic offsets and their related ages yields a maximum left-lateral slip rate of ~5.3 mm/yr for the CFZ during Holocene. The maximum length of independent seismogenic fault segments varies from ~70 to ~100 km that could produce a characteristic earthquake with a magnitude of Mw =7.2 to 7.4 and recurrence interval of ~750 years.We propose a geodynamic model in which the EFZ is involved in a NNW-trending dextral shear zone between Central Iran and Eurasia. This implies that the EFZ forms a complex right-lateral transpressional relay zone between the eastern and northeastern Arabia-Eurasia convergence boundaries. The northward motion of Central Iran relative to Eurasia is accommodated by shortening on NW-trending reverse faults, and is transferred northward via NNW-trending dextral faults

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Gurgel, Silvana Praxedes de Paiva. "Evolu??o morfotect?nica do maci?o estrutural pereiro, Prov?ncia Borborema". Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18364.

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Made available in DSpace on 2015-02-24T19:48:44Z (GMT). No. of bitstreams: 1 SilvanaPPG_TESE_pag119_final.pdf: 4384081 bytes, checksum: f4e3889e03bd2b77ef4e8f1b271723a8 (MD5) Previous issue date: 2012-08-06
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The Northeast relief was described by the Pediplanation Model. This action discards the theoretical basis of post-Cretaceous tectonic evolution of the landscape. Through this model the Massif Pereiro - MP, Borborema Province, was established as part of the Tablelands Area Residual Sertanejos. The present work aims to establish the post- Cretaceous morphotectonic evolution of the MP by geomorphological and geological mapping using Geographic Information System, Remote Sensing and dating of sediments by Single Aliquot Regenerative-dose (SAR). The MP is contained in the core semi-arid, annual precipitation of 600-800 mm / year. The MP is NE-SW, is limited by Shear Zone Jaguaribe (ZCJ) and Portalegre Shear Zone (ZCPa), the same attitude, and crossed by several other shear zones. These shear zones show evidence of brittle Cenozoic reactivation, mostly as normal faults and shallow crustal level. The Quaternary sedimentation around the MP focuses on fault escarpments in a general pattern cascade, where ages decrease from the summits of the steep foothills. The ages of 51 sediment samples indicate a correlation with global climate following pulses: Last Interestadial-UI, the Last Glacial Maximum - LGM and the transition Pleistocene / Holocene, while the latter focus on 18 of 51 samples dated. This study also finds evidence of a new quaternary basin, here called Merejo Basin. Through these results it is concluded that no evidence of post-Cretaceous tectonic evolution of morphological MP, as their retreat along the fault scarps, invariably following the trend of the shear zones. The erosion of cliffs in large time scale is controlled by weakness zones generated by faults on the other hand the erosion of cliffs in short time, with the formation of deposits and colluvial horizons pedogenizados, has climate control. It was also found that in the study area there is a preponderance of past and current tectonic erosion processes on the morphological evolution
O relevo do Nordeste foi descrito por meio do modelo de pediplana??o. Esta base te?rica descarta a atua??o da tect?nica p?s-cret?cea na evolu??o da paisagem. Atrav?s deste modelo o Maci?o do Pereiro MP, Prov?ncia Borborema, foi definido como parte do Dom?nio dos Planaltos Residuais Sertanejos. O presente trabalho tem por objetivo estabelecer a evolu??o morfotect?nica p?s-cret?cea do MP, atrav?s da cartografia geol?gica e geomorfol?gica com uso de Sistema de Informa??o Geogr?fica, Sensoriamento Remoto e data??o de sedimentos por Single Aliquot Regenerative-dose (SAR). O MP est? contido no n?cleo semi?rido, de precipita??o anual entre 600 a 800 mm/ano. O MP tem dire??o NE-SW, ? limitado pela Zona de Cisalhamento de Jaguaribe (ZCJ) e Zona de Cisalhamento Portalegre (ZCPa), de mesma atitude, e atravessado por v?rias outras zonas de cisalhamento. Estas zonas de cisalhamento apresentam evid?ncias de reativa??o fr?gil cenozoica, na sua maioria como falhas normais e de n?vel crustal raso. A sedimenta??o quatern?ria em torno do MP se concentra em escarpas de falhas, em um padr?o geral em cascata, onde as idades diminuem das cimeiras aos sop?s das escarpas. As idades de 51 amostras de sedimentos indicam correla??o com seguintes pulsos clim?ticos globais: ?ltimo Interestadial- UI, o ?ltimo M?ximo Glacial - UMG e a transi??o Pleistoceno/Holoceno, sendo que nesta ?ltima concentram-se 18 das 51 amostras datadas. O presente trabalho tamb?m encontra evid?ncias de uma nova bacia quatern?ria, aqui denominada de Bacia Merejo. Atrav?s destes resultados conclui-se que h? evidencia de tect?nica p?s-cret?cea na evolu??o morfol?gica do MP, pois as suas escarpas recuam paralelamente ?s falhas, seguindo invariavelmente o trend das zonas de cisalhamento. A eros?o das escarpas em grande escala de tempo ? controlada pelas zonas de fraqueza geradas pelos falhamentos, por outro lado ? eros?o das escarpas em curtos espa?os de tempos, com a forma??o dos dep?sitos coluvionares e horizontes pedogenizados, possui controle clim?tico. Concluise ainda que na ?rea de estudo haja a preponder?ncia da tect?nica pret?rita e atual sobre os processos erosivos na evolu??o morfol?gica

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Yu, Wang, i 王昱. "Morphotectonics in Taoyuan — Hsinchu Area, Northwestern Taiwan". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/69871825199744682286.

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碩士
國立臺灣大學
地質科學研究所
91
Taoyuan─Chungli tablelands are located in the northwestern Taiwan, a transition zone between two different stress fields: extension and compression in the north and south respectively. The tablelands are composed of several different steps of river terraces developed by the paleo-Tahan River. The youngest terrace was abandoned around 30 ka when the headwater was captured by the Tanshui River that flows northeastward into Taipei basin. We use digital elevation model (DEM) in resolution of 40m and aerial photos to identify the tectonically influenced features on terrace surfaces. Two major groups of landforms were identified based on their orientations. The first group is roughly striking ENE and comprises four main linear scarps: the Shuanglienpo, northern and southern Yangmei, as well as the Lungtan-Hsinpu. They are obviouly related to two active anticlines (the Hukou and Pingchen), indicating a long developing history of terrace deformation. Considering the corresponding structures, we suggest that they may be created by asymmetric folds, i.e., a steep forelimb and a gentle back-limb beneath. One cross-section across linear scarps is reconstructed using the idea of the reactivated normal fault and shear fault-bend fold suggested by Dr. John Suppe. The result shows two asymmetric folds “Hukou” and “Pingchen” convergent to each other. This interpretation is also supported by the geomorphology data upon these structures. As a result of limb development, four main linear scarps can be apparently explained as fold scarps, which is different from the previous interpretation that the southern Yangmei linear scarp is a fault scarp created by the supposed Hukou fault. The second group is only distributed in the southern area of these tablelands. It is oriented WNW but relatively discontinuous. Here we found out not only linear scarps but also some complicated landforms such as pressure ridges, linear valleys, linear scarps, as well as beheaded rivers. By these features, we suggest two right-lateral faults, the western one inversed from the pre-orogeny normal fault, while the eastern one is a tear fault. The total slip of these structures is larger than 1 km base on surface observations and structure interpretations. However, due to the lack of age control in this area, so far the long-term activities of these structures remain unknown. Nevertheless, the preliminary geodetic survey on the youngest surface indicates that the Hukou anticline is still active in the last 30 ka.

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Kaye, Grant David. "Testing spatial correlation of subduction interplate coupling and forearc morpho-tectonics". Thesis, 2003. http://hdl.handle.net/1957/9011.

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The two largest earthquakes ever recorded, the 1964 M[subscript w] 9.2 Alaskan and 1960 M[subscript w] 9.5 Chilean, occurred on seismogenic plate interfaces at subduction zones. It has been theorized that the catastrophic failure of a locked zone along the contact between the downgoing slab and the upper plate causes these earthquakes, although determinations of the position, attitude and extent of this locked zone vary from model to model. Four methods used to constrain the positions of the locked zones are: (1) historical great earthquake rupture extents, (2) heat flow/thermal profiles along the seismogenic plate interface, (3) patterns of surface deformation across the subduction zone forearc, and (4) spatial patterns of upper plate seismicity. Secondary parameters, such as subducted sediment thickness, upper plate lithology, and dip angle of the subducting slab likely play a role in locked zone location as well. In addition to a locked zone, the upper plate of most subduction zones is marked by paired inner and outer forearc highs and basins between the deformation front (trench) and the volcanic arc. Although such surface morphological features are easy to recognize, their spatial and geometric relationships to the locked zone have not been investigated systematically. This thesis investigates correlation between the spatial position of these morpho-tectonic features and the underlying locked zone at the Aleutian, Alaskan, Cascadia, Costa Rican, Javanese, Sumatran, Nankai, and Southern Chilean subduction zones. For all subduction zones other than Cascadia, which has yet to experience a great earthquake in historical times, the applied means of determining the position of the locked zones place them on plate interface regions between the inner and outer forearc highs. A strong correlation exists between dip of the downgoing plate and the width of both the locked zone and the spacing of the forearc morphologic elements for each of the subduction zones examined. The concept of comparative subductology is updated and enhanced in this study by creating GIS databases incorporating geological, seismological, geodetic, and geophysical observations. Correlations between surface morphological features and geologic and geophysical observations provide insight into controls on the position of the locked zone responsible for great earthquakes within the eight subduction zones examined, indicating that forearc morphology and interplate coupling are related via basic subduction parameters and the structural-tectonic regime of the forearc region.
Graduation date: 2004

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