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McClay, K. R. "Structural geology and tectonics /." Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09SD/09sdm126.pdf.
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Kiani, Tayebeh. "Modeling for geospatial database : application to structural geology data : application to structural geology data." Paris 6, 2010. http://www.theses.fr/2010PA066057.
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L’objectif de cette étude est de créer un modèle de base de données dans un système d’information géographique afin d’archiver, analyser, présenter et de diffuser des données observées lors des analyses de géologie structurale. Le modèle de données est conçu pour atteindre quatre objectifs: établir un vocabulaire partagé par les spécialistes, modéliser les concepts de géologie structurale, produire des cartes dérivées des cartes géologiques d’Iran et fonctionner avec un logiciel de système d’information géographique. Un ensemble de classes conceptuelles est alors identifié pour représenter les concepts de base de la géologie structurale pour les objets contacts, plis, foliations, fractures (failles et joints), linéations et zones de cisaillement. Un modèle conceptuel unifié est construit pour chaque famille. Puis, le modèle logique de données, présenté en langage UML à l’aide de diagrammes de classes statiques, est développé. Les étapes dans l’élaboration du modèle de données incluent l’identification des classes, la création des diagrammes de classes, la déclaration des attributs et des associations. Les cartes géologiques d’Iran au 1:250 000 sont ici utilisées comme base de présentation d’un modèle conceptuel permettant l’unification et la préparation d’une légende unique d’un ensemble pilote de quatre cartes. Les résultats de l’étude fondent les principaux concepts et les structures des données pour représenter l’information spatiale en géologie structurale et fournissent un modèle pour créer une base de données permettant la gestion des données de géologie structurale avec un système d’information géographique
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Lisle, Richard John. "Techniques of quantitative structural geology." Thesis, University of Birmingham, 2007. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446367.
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Miller, John Frederick. "Structural geology of the Ohio Shale." Connect to resource, 1996. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1163610177.
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Zahid, Khandaker Uddin Ashraf. "Provenance and basin tectonics of Oligocene-Miocene sequences of the Bengal Basin, Bangladesh." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Thesis/ZAHID_KHANDAKER_14.pdf.
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Bauer, Tobias. "Structural and sedimentological reconstruction of the inverted Vargfors basin : a base for 4D-modelling." Licentiate thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17596.
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The Palaeoproterozoic Skellefte mining district in northern Sweden covers an area of 120 by 30 km and is one of the most important mining districts in Europe, producing mainly Zn, Cu, Pb, As and Au from volcanogenic massive sulfide (VMS) and orogenic gold deposits.Detailed mapping of structures and stratigraphy within the sedimentary Vargfors Group combined with a structural analysis revealed a syn-extensional fault pattern of NW-SE-trending normal faults and associated NE-SW-trending transfer faults, creating the segmented sedimentary Vargfors basin. It comprises distinct fault-bound compartments, which incluence the sedimentary stratigraphy in each of these compartments.Syn-rift subsidence affected the sedimentary conditions from near-shore to shallow submarine environment.Intensive fault movements associated with mafic volcanic activity along these faults resulted in the rapid uplift of the oldest phase of the Jörn intrusive complex and/or subsidence of its surrounding areas. Subsequent erosion of the intrusive rocks led to the formation of a tonalite to granodiorite bearing conglomeratic sequence, representing an alluvial fan. Further uplift to the north of the district resulted in the erosion of Arvidsjaur volcanic rocks and the formation of a braided river system. Subsidence of the intrusive complex and/or a sedimentary coverage on top of the same caused a break in sedimentation of tonalite to granodiorite clasts. Stratigraphical evolution of the sedimentary rocks and the Vargfors Group - Skellefte Group contact relationships show that rifting started in the centre and proceeded with time towards SE and NW. Subsequent basin inversion resulted in the reactivation of the existing normal faults along a carbonate-rich basal layer forming asymmetric synclines. Primary geometries of sedimentary strata within each fault-bound compartment controlled their deformation styles. Furthermore, strain was partitioned into the faults, forming high strain zones along the basin margins, where foliations parallel the main faults, and low strain domains in the core of the basin, where foliation is oblique to the main structural grain of the basin. This oblique foliation is either a result of a rotating stress field or a transpressional regime. This case study on basin inversion gives implications for accretion processes along the Svecokarelian Craton margin as well as forthe formation of VMS-deposits and their possible transposition. Basic modelling of the main geological boundaries in the central Skellefte district was performed by integrating data from regional to outcrop scale using the GoCAD (Paradigm) software platform. Available data included geographical and geological data, which were imported from ArcGIS (ESRI) as well as drill-hole data, seismic profiles, resistivity and gravimetry profiles and EM-profiles. Creation of the main geological boundaries utilized GoCAD and SPARSE (Mirageoscience) algorithms, whereas structural geological data was exclusively modelled with SPARSE. Furthermore, this study provides a base for refining the 3-dimensional model and developing a 4-dimensional model, showing the geological evolution of the Skellefte district.Godkänd; 2010; 20101029 (tobbau); LICENTIATSEMINARIUM Ämnesområde: Malmgeologi/Ore Geology Examinator: Professor Pär Weihed, Luleå tekniska universitet Diskutant: Dr Peter Sorjonen-Ward, GTK, Kuopio, Finland Tid: Torsdag den 16 december 2010 kl 10.00 Plats: F531, Luleå tekniska universitet
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Metzger, Nicolai. "Structural controls on the shear zone hosted, IOCG-style Kiskamavaara Cu-Co-Au mineralization." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-74068.
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Sweden is the largest producer of iron ore in the European Union, as well as amongst the top producers for base and precious metals. Much of its mineral wealth derives from northern Norrbotten, type locality of the Kiruna-type-magnetite-apatite ores. Besides the massive iron ore bodies, the region is further recognized as important iron-oxide-copper-gold (IOCG) province, with the world class, Aitik Cu-Au-Ag-(Mo) deposit as its most prominent example (1061 Mt with 0,22% Cu; 0,15ppm Au; 1.3ppm Ag), (Wanhainen et al. 2012, Boliden 2017). The close spatial relation between Aitik, further IOCG style mineralization and the Nautanen Deformation Zone (NDZ), a crustal-scale, approximately N-S trending shear system provides important insights into the complex connection between deformation, reactivated fault systems and the different mineralizing events affecting the area during the Svecofennian period (1.9-1.8 Ga). Whereas this connection is well constrained within the Gällivare mining district (c.f. Martinsson and Wanhainen 2004, Wanhainen et al. 2012, Bauer et al. 2018, Lynch et al. 2018), the northern and southern continuations of the NDZ and its potential to host further mineralization remain unknown. During this study, an area around the Kiskamavaara Cu-Co-Au mineralization was investigated to link its tectonic evolution with regional metallogenic events and compare its alterations and structural regime to that of the highly prospective NDZ. It is suggested that the region was affected by at least two deformation events, D1 and D2, both causing a characteristic alteration assemblage, structural patterns and related mineralization. The identification of pseudotachylitic structures and supergene mineralization argues for a late, brittle, upper crustal event with hydrothermal character during D2. Constraining the Kiskamavaara Cu-Co-Au mineralization to this event allows to propose a genetic link to the known IOCG-style mineralization in the Nautanen area that are generally related to a late, 1.80 Ga period of hydrothermal activity. It is suggested that the Cu-Au mineralization in the Kiskamvaara and Nautanen area formed under similar conditions, hence arguing for a single high strain zone in favor over several locally constrained zones of crustal weakening. If supported in further studies, this finding of a highly prospective NDZ beyond its known extend, might justify more intense exploration in highly strained lithologies between the Kiskamavaara and Nautanen area, as well as north of Mattavaara and south of Gällivare.
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White, Thomas West Steltenpohl Mark G. "Geology of the 1:24,000 Tallassee, Alabama, Quadrangle, and its implications for southern Appalachian tectonics." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Geology_and_Geography/Thesis/White_Thomas_41.pdf.
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Tozer, Craig Hampton. "The influence of inherited structures on the Cenozoic orogeny of the Kyrgyz Tien Shan /." view abstract or download file of text, 2004. http://wwwlib.umi.com/cr/uoregon/fullcit?p3147837.
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Thesis (Ph. D.)--University of Oregon, 2004.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 171-180). Also available for download via the World Wide Web; free to University of Oregon users.
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Andersson, Joel. "Structural evolution of two ore-bearing Palaeoproterozoic metasupracrustal belts in the Kiruna area, Northwestern Fennoscandian Shield." Licentiate thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72034.
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In this project, two key study areas in the northwestern Fennoscandian Shield are under investigation. The “Western supracrustal belt” and “Central Kiruna area” are both located along lithotectonically comparable Rhyacian-Orosirian metasupracrustal belts and both areas are characterized by iron oxide-apatite (IOA) and iron oxide-copper-gold (IOCG)-style mineralizations and related hydrothermal alterations. The area is in general well studied but the structural evolution remains unresolved. In order to build a structural framework for the Kiruna area, the number of deformation events, kinematics, geometries, mineralogy and interrelationships of the dominant structures are under focus in this study. The paired structural-alteration configuration is targeted in order to constrain the relative timing of dominant structures and mineral alteration parageneses in order to use these systems as structural vectors of mineralized systems. Furthermore, the Orosirian stratigraphy is re-evaluated in order to constrain the pre-compressional geological history of the study areas. This is important as it controls the character of the structural development during subsequent compression forming the sub-surface architecture as we see today. The Orosirian stratigraphy suggests the development of a syn-extensional basin in Kiruna where iron oxide-apatite deposits were emplaced. This basin was subsequently inverted accompanied by shearing, folding, and faulting during D1 and D2, refolded during D3, and further fractured during D4. The shortening directions inferred during the deformation events suggest a clockwise rotation of the stress field from NE-SW (D1) to E-W (D2) and finally NNW-SSE (D3). Regional scapolite ± albite alteration is interpreted to be coeval with regional amphibole + magnetite alteration during D1. Mineral alteration parageneses linked to D2 is more potassic in character and often structurally controlled by shear zones. As a regional generalization, the potassic dominated D2-alteration is characterized by sericite ± epidote ± biotite ± chlorite ± magnetite ± sulphide ± K-feldspar. Fe- and Cu-sulphides are concentrated into brittle D2-structures suggesting that a IOCG-style of mineralization can be linked to the potassic D2 event. This implies that iron oxide-apatite emplacement can be linked to the basin development phase, whereas epigenetic Fe- and Cu-sulphides are linked to the basin inversion-phase of the geological evolution, and hence, separated in time and probably not directly genetically linked in Kiruna.
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Tang, Lai-kwan Denise. "Geology of Tuen Mun Area, NW Hong Kong an updated model /." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B3829283X.
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Jonsson, Linus. "Seismic tomography as an instrument for structural evaluation in the Printzsköld and Alliansen ore bodies, Malmberget." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64918.
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The Malmberget deposit is one of the major apatite iron ores in Europe, located in northern Norrbotten. As the mining in Malmberget proceeds deeper more challenges with the stability have been faced. When the stress distribution of a rock mass exceeds the rock strength energy in form of seismic waves is released. In Malmberget, a monitoring system consisting of 200 geophones is installed which detects all seismic waves in the area. Based on data received from the monitoring system, LKAB has achieved to generate a seismic tomography model over the velocity variations of the seismic waves as they propagate in the rock mass. The present study evaluates how the seismic tomography model can be used as a tool for reconstructing the structural characteristics of the two ore bodies Printzsköld and Alliansen. The aim is to clarify how seismic tomography can be combined with structural data to increase the geological knowledge of the Malmberget mining area. Based on structural measurements from the mine in combination with geotechnical data (RQD, Jr, Ja) two structural geological models were constructed. One model visualizing the orientation of the foliation and the other presenting brittle joints and fractures. The models were constructed in order to compare them with the seismic tomography model to outline structures and characteristics in the rock mass. The foliation in Printzsköld has a steep NE-SW orientation. In the eastern part where Printzsköld connects to Alliansen, the orientation changes to NW-SE, indicative of a fold structure. The joints and fractures in the study area appeared as 4 sets. One set appeared parallel to the foliation and one perpendicular to it. The two other sets were oriented E-W almost perpendicular to each other with a shallow dip. The rock quality in Printzsköld shows a pattern of increasing quality deeper down with zones of lower quality following the magnetite ore body. The previous identified deformation zone DZ031 appear as an important structure for unstable zones in Printzsköld. The current results suggest that the seismic tomography model needs more investigation but shows promising results as an indicative instrument delineating large scale structures and large zones with lower rock quality.Gruvan i Malmberget är belägen i norra Norrbotten och utgör en av de största apatitjärnmalmerna i Europa. Med tiden försätter brytningen i Malmberget på allt större djup. Det innebär en större utmaning med stabiliteten i gruvan då spänningarna i berget kan tänkas öka längre ner. När bergsspänningarna överskrider bergets hållfasthet sker en frigörelse av energi i form av seismiska vågor. I Malmberget finns ett system av 200 geofoner som detekterar alla seismiska vågor i området. Baserat på data som mottagits från övervakningssystemet har LKAB lyckats framställa en seismisk tomografimodell över de seismiska vågornas hastighetsvariationer när de breder ut sig i bergmassan. I studien granskas hur den seismiska tomografin kan användas som ett verktyg för att utvärdera geologiska strukturer i de två malmkropparna Printzsköld och Alliansen. Syftet är att klargöra om seismisk tomografi kan kombineras med strukturdata för att öka den geologiska kunskapen i Malmbergets gruvområde. På basis av mätta strukturer i gruvan i kombination med geoteknisk data (RQD, Jr, Ja) konstruerades två strukturgeologiska modeller i syfte att jämföra modellerna mot den seismiska tomografin. Resultatet från studien visar att foliationen i Printzsköld har en NÖ-SV orientering med en brant stupning. I den östra delen som förbinder till Alliansen ändras orienteringen succesivt till NV-SÖ, vilket indikerar en veckning av foliationen. De dominerande riktningarna för sprickor och frakturer i Printzsköld och Alliansen uppträdde som 4 set. Ett set var orienterat parallellt med foliationen och ett vinkelrätt mot det förevarande. De två andra sprick riktningarna var orienterade Ö-V nästintill vinkelrätt mot varandra med en flack stupning. Bergskvalitén i Printzsköld visade ett mönster av att förbättras djupare ner. Zoner med lägre bergskvalité följer malmkroppen. Den seismiska tomografin uppvisade korrelation med storskaliga strukturer samt stora områden med minskad berghållfasthet. Den tidigare identifierade deformations zonen DZ031 uppträder också som en viktig struktur instabila områden i Printzsköld. Utvärderandet av resultaten tyder på att den seismiska tomografin behöver fortsatt mer undersökningsarbete men visar lovande resultat av att fungera som ett vägledande instrument för att definiera storskaliga strukturer och större områden med sämre bergskvalité.
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Gleason, James Donald. "Paleozoic tectonics and sediment sources of the Ouachita fold belt, Arkansas-Oklahoma and West Texas: An isotopic and trace element geochemical study." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186844.
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Ordovician through Pennsylvanian strata of the Ouachita and Marathon sedimentary sequences show correlated Nd-Sr isotopic relations, Th/Sc ratios and REE patterns typical of evolved upper crustal sources, indicating that the 2000 km long Ouachita-Marathon fold belt consists primarily of recycled crustal materials. wi thin this sequence, Nd isotopes distinguish three distinct provenance groups: 1) Lower to Middle Ordovician hemipelagites and quartzose turbidites with ε(Nd)(t) = -13 to -16 (T(DM) = 1.8 to 2.1 Ga); 2) Upper Ordovician through Pennsylvanian hemipelagites and quartzolithic turbidites with ε(Nd)(t) = -6 to -10 (TOM = 1.4 to 1.7 Ga); 3) Mississippian tuffs with ε(Nd)(t) = -2 (TOM = 1.1 Ga). These data record a rapid Ordovician (ca. 450 Ma) shift in sedimentary sources within the off-shelf passive-margin sequence of deep-marine cherts and shales. Ouachita Silurian turbidites (ε(Nd) = -7 to -8) are isotopically identical to Middle Ordovician Taconic turbidites of the Sevier basin (Tellico Formation) in eastern Tennessee (ε(Nd) = -7 to -8), suggesting that Appalachian clastic wedges supplied Ouachita deep-sea turbidites beginning in the Late Ordovician. Pennsylvanian non-marine sandstones and shales from the Arkoma, Illinois, and Black Warrior basins have ε(Nd) = -7.5 to -10.0, similar to the thick (>10-12 km) Ouachita Carboniferous turbidite flysch sequence (ε(Nd) -7.5 to -9.6). The remarkable isotopic homogeneity of sediments delivered to the Ouachita-Appalachian region over this period implies extremely effective mixing and dispersal processes on a large (continent-wide) scale, consistent with a collisional belt provenance. A long-lived (ca. 150 Ma) tectonic link between the Appalachians and Ouachitas is thus implied by these data. Mississippian silicic ash-flow tuffs have trace-element and Nd isotopic compositions consistent with a continental-margin arc source. The active volcanic arc which erupted these tuffs apparently extended at least 1000 km from the Ouachita region to south of the Marathon region, but did not supply a significant component of the flysch. The data are consistent with submarine fan models of Ouachita flysch sedimentation demonstrating dominantly longitudinal transport down the axis of a Carboniferous remnant ocean basin from sources to the east. A model is proposed for the evolving Ouachita-Marathon suture between Laurentia and Gondwana, expanding upon Graham et a1. (1975), whereby dominantly Appalachian-derived seafloor detritus was swept up along the flanks of an approaching arc-trench system into sUbduction complexes and recycled incrementally along the length of the collision zone into the Marathon region.
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Armstrong, Thomas Robert. "Structural and Petrologic Evolution of Acadian Dome Structures in Southern Vermont." Diss., Virginia Tech, 1995. http://hdl.handle.net/10919/37857.
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Petrologic and thermobarometric studies, coupled with geologic mapping and structural analysis, provide critical evaluation of several different models for Acadian (Late Silurian to Middle Devonian) dome evolution in southern Vermont. Previous models considered diapiric uprise and composite nappe-stage crustal thickening and subsequent diapirism as likely causes of dome formation. Both of these previous models result in symmetrical distribution of P-T values about the dome structures with corresponding coreward increases in temperature, and typically, coreward decrease in associated pressures. Thermobarometric calculations made during this study demonstrate that both P and T increase eastward across the entire region and are not symmetrically distributed about dome axes. The P-T data coupled with petrographically derived relative age relationships and available geochronology also suggest that attainment of peak metamorphic conditions and concurrent dome-stage deformation are diachronous and young from west to east. These relationships are consistent with new geologic mapping and structural analysis which show that all of the domes in southern Vermont are low-amplitude fold interference structures. A current tectonic model indicates that Acadian Barrovian metamorphism in this region was a consequence of west-directed crustal thickening of an eastward dipping tectonic wedge, presumably from the Bronson Hill Terrane; an Ordovician arc sequence. The basal surface of this allochthonous mass projects above the present land surface within this area. Accretion of lower-plate rocks (of this study) into the thrust complex and continued west-directed thrusting of the accreted package over a seismically recognizable east dipping ramp structure provided the necessary geometry and mechanism for dome-stage fabric development, calculated uplift rates (1.2 to 1.7 km/m.y. and west to east younging of Acadian structural and metamorphic evolution.
Thermobarometric and geochronologic estimates of metamorphic pressure - temperature (P-T) conditions and metamorphic cooling ages were used to constrain the required thermal and tectonic input parameters for use in one-dimensional thermal modeling of an Acadian (Silurian-Devonian} tectonotherma! regime within the pre-Silurian Taconide zone of southern Vermont. This regime includes: 1) garnet-grade rocks from the eastern flank of an Acadian composite dome structure (Sadawga Dome; the western domain); 2) staurolite/kyanite-grade rocks from the western flank of a second composite structure, the Athens dome (eastern domain). Results from thermal modeling include development of P-T paths, temperature-time (T-t) and pressure-time (P-t) curves, related values of maximum temperature and pressure, pressure conditions at maximum temperature, predicted closure ages for radiogenic phases, and integrated uplift and cooling rates.
Thermal modeling results are remarkably similar to independently obtained data for Acadian regional metamorphism in western New England, and provide some important constraints on regional thermal evolution: 1) pressure values contemporaneous with peak temperature on P-T paths may be substantially lower than actual maximum pressure (> 2.5 kbars); 2) differences in peak temperature for rocks initially loaded to similar crustal depths (garnetgrade vs. staurolite-grade), differences in calculated uplift rates, and differences in Ar closure ages, are consequences of variations in durations of isobaric heating events (or "residence periods"), and differences in actual tectonic uplift rates. These modeling results are internally consistent with structural model that suggests west to east younging of specific Acadian deformations and resultant diachroneity of peak metamorphic and Ar closure ages. Regional variations in timing and conditions of metamorphism may be controlled by diachronous deformational events coupled with variations in crustal levels to which rocks were initially loaded during the ca. 400 Ma onset of Acadian orogenesis in western New England.Ph. D.
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Ferreira, Samuel Nunes [UNESP]. "Geologia estrutural aplicada às rochas ornamentais na Pedreira Knawa, Cláudio (MG)." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/92887.
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Este trabalho apresenta os resultados de mapeamento geológico-estrutural de detalhe numa área piloto (Pedreira Knawa, Cláudio Estado de Minas Gerais) em escala de 1:200 e dos estudos de reconhecimento geológico em suas áreas adjacentes, e da aplicação do método de GPR na identificação de estruturas geológicas na Pedreira Knawa. Onde seu objetivo principal é proporcionar um direcionamento dos trabalhos geológico-estruturais na pedreira, visando otimizar a extração da rocha. As rochas que compõem esta região abrangem tanto rochas do complexo gnáissico-migmatítico de médio a alto grau denominado de Complexo Campo Belo quanto de suas supracrustais o Supergrupo Rio das Velhas, que encontram-se inseridos dentro do contexto geotectônico do Cráton do São Francisco Meridional. A Pedreira Knawa está localizada nos domínios da zona de cisalhamento Cláudio, e o arcabouço litológico predominante corresponde a um biotita gnaisse bandado fortemente migmatizado e deformado, de coloração cinza claro a cinza esbranquiçado, com pequenas quantidades de mobilizados félsicos de coloração rósea e xenólitos de rochas básica e ultrabásicas. As estruturas exibidas por esta rocha são predominantemente gnássica a migmatítica e revelam em escala de detalhe uma grande heterogeneidade, permitindo individualizar outros litotipos dentro deste arcabouço. Podem ser identificados da seguinte forma: biotita gnaisse bandado (rocha predominante), xenólitos de anfibolito e ultramafitos, granito, bandas dioríticas, veios pegmatíticos, zonas migmatíticas, veios migmatíticos de zonas de cisalhamento e diques de anfibolitos. A análise das feições estruturais e geológicas, observadas principalmente na área da pedreira e em seu entorno, permitiu identificar uma seqüência de três eventos geológicos estruturais principais, impressos nos gnaisses (Dn, Dn+1 e Dn+2), além da deposição...
The results of a detailed geologic-strutural mapping in the scale 1:200 are presented for a pilot area (Knawa quarry in the village of Cláudio, state of Minas Gerais). Geologic reconnaissance studies in adjacent areas and GPR surveys were performed to identify geologic structures. The main objective of those works was to guide geologic-structural mapping in the quarry to optimize production of dimension stones. The rocks in the region spam from the highly metamorphic Campo Belo composed of gneissic-migmatites to supracrustal Rio das Velhas supergroup in the geotectonic context of the southern São Francisco Craton. Knawa quarry is located in the domains of the Cláudio shear zone, where predominant lithology corresponds to a banded stronghy migmatized and deformed biotite gneiss showing ligh grey to whitish color, small felsic masses, pink in color and xenoliths of basic and ultrabasic rocks. These rocks predominantly exhibit gneissic to migmatitic structures but are very heterogeneous, allowing to individualise other lithotypes within the framework, as such: banded biotite gneiss (predominant) xenoliths of anfobolite and ultramafic rocks, granite, dioritic bands, pegmatitic veins migmatitic zones, migmatitic veins in shear zones and anfibolitic dykes. From the analysis of the structural and geologic features a sequence of structural events was identified, consisting of three main geologic events in the gneisses (Dn, Dn+1& Dn+2) plus the deposition deformation of the supracrustal and the intrusion of basic dykes. Evaluation and optimization of mining started from the identification of the geologic factors that affect production. These parameters were drawn from the assessment of the geologic map and of the commercial recovery deriving maps of optimized and three-dimensional geologic models. The volume calculation of the fifth level of the quarry identified a total volume of 33731, 28 m3, the volume of sectors with a recovery below 15% equal to.
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Massucatto, Armando José [UNESP]. "Caracterização estrutural do embasamento do Grupo Araí, na zona externa da faixa Brasília (GO)." Universidade Estadual Paulista (UNESP), 2003. http://hdl.handle.net/11449/103016.
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massucatto_aj_dr_rcla.pdf: 7707531 bytes, checksum: 674b102878234ea9505b57b68ec0de3e (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A área de estudo, objeto desta tese de doutoramento, situa-se na porção nordeste do estado de Goiás, na região de Cavalcante. Nesta região são encontradas rochas do embasamento da Faixa de Dobramentos Brasília, composto por rochas do Complexo Granítico-gnáissico, mega veios de quartzo e Formação Ticunzal. Recobrindo estas rochas são visíveis os metassedimentos do Grupo Araí. As rochas do embasamento da Faixa de Dobramentos Brasília na área de estudo se apresentam fortemente deformadas, mostrando uma alta complexidade estrutural, o que indica que foram submetidas a diferentes eventos deformacionais. Para um melhor entendimento da evolução geólogica da área buscou-se através de diferentes técnicas e ferramentas a separação dos eventos deformacionais que atuaram sobre a região. Os trabalhos realizados levaram a identificação de 5 foliações distintas, sendo que as mesmas foram hierarquizadas e separadas, em função de sua geração, em 3 eventos deformacionais. Para refinar a separação destes eventos deformacionais foram realizadas datações em muscovitas pertencentes às respectivas foliações, utilizando-se o método 40Ar/39Ar. O Evento denominado genericamente de 1, apresenta uma foliação (S1) com direção próxima a EW, mergulho subvertical. Tal foliação é gerada como resposta a uma compressão de direção próxima a NS. As datações realizadas em micas brancas formadas durante este evento, indicam idades mínimas de 1.5 Ga. O Evento 2, decorrente de uma compressão de direção próxima a EW, é responsável pela geração de uma foliação (S2) com direção próxima a NS, que apresenta um mergulho vertical. Associa-se a esta fase uma lineação de estiramento em geral vertical e localmente de baixo ângulo. As datações realizadas apontam para idades mínimas de 1.4 Ga, para micas brancas geradas durante este evento...
The studied area in this PhD thesis is located in the northeast portion of Goias State, near Cavalcante Town. Basement rocks of Brasilia Fold Belt, composed basically by Granitic-Gneiss Complex, mega quartz veinz and the Ticunzal Formation, characterize this area. Overlying these rocks are the Araí Group Metassediments. The basement rocks of Brasilia Fold Belt, in the studied area, are strongly deformed, showing a highly structural complexity, which indicate these rocks were submitted by different deformational events. For a better understanding of geological evolution, different techniques and tools to distinguish the deformational events have been applied. The work done defined the identification of five different foliations, which were ordered and separated in three different deformational events because its generations. To refine its events separation, 40Ar/39Ar dating in muscovites belonging in each foliation has been done. The Event denominated generally by 1 presents an EW direction foliation (S1) with a sub vertical dipping. Such foliation was generated as consequence for an NS direction compression. The dating done in white micas formed during this event, yielded a minimum age of 1.5 Ga. The Event 2, consequence of a close EW direction compression, generated a close NS direction foliation (S2) with vertical dipping. The white micas dating suggest a minimum age of 1.4 Ga for this event. Petrographic analysis indicated rocks that were submitted by the Events 1 and 2, were affected by similar metamorphism conditions, where might have reached temperatures between 450 and 500o C. The mega quartz veins possibly have been generated during the Event 2. Accomplished studies showing that its geometries are conformable with the cinematic aspects found in this event...(Complete abstract click electronic access below)
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Silva, Carlos Humberto da [UNESP]. "Evolução geológica da faixa Brasília na região de Tapira, Sudoeste de Minas Gerais." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/103025.
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silva_ch_dr_rcla.pdf: 785091 bytes, checksum: 6e1bc5d4c82f715e1777e80217b4a4b6 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presente trabalho apresenta uma proposta de evolução geológica Neoproterozóica de um segmento da Faixa Brasília Meridional, na região de Tapira (SW de Minas Gerais). A partir de mapeamento geológico detalhado é da caracterização estrutural e metamórfica. As rochas desta região apresentam uma complexa evolução estrutural, onde a principal estrutura reconhecida é uma foliação em baixo ângulo (S4) orientada em média N43W/30SE, à qual associa-se uma lineação de estiramento e/ou mineral orientada N50W/10, atribuídas à fase D4. A foliação S4 normalmente é reconhecida como uma clivagem de crenulação, cuja superfície crenulada é uma foliação S2, sub-paralela ao acamamento sedimentar (S0). Em alguns locais S4 manifesta-se como uma xistosidade ou clivagem contínua. A foliação S4 também afeta dobras normais de escala quilométrica relacionadas à fase D3. Adicionalmente são reconhecidos dois conjuntos de dobras pós-fase principal com eixos de caimentos suaves e planos axiais íngremes, sendo os eixos de D5 de direção NW e os eixos de D6 de direção NNE. Relacionada à fase D5 associam-se três zonas de cisalhamento transcorrentes quilométricas, a partir das quais sub-divididiu-se a área em três domínios tectono-estratigráficos. No domínio oeste (DW) ocorrem duas escamas tectônicas separadas por falha de empurrão. A escama 1 apresenta rochas metapelíticas e pelítico-grafitosas com intercalações psamítica. A associação mineral muscovita + quartzo + granada l clorita l biotita l cloritóide l grafita l albita, permitem situar as rochas dessa escama na fácies xisto verde superior (zona da granada), com condições de T e P estimadas em 540°C e 7,5 kbar. Na escama 2 predominam rochas pelíticas com intercalações psamíticas, adicionalmente ocorrem intercalações de hornblenda-granada-mica xistos e rochas metamáficas e metaultramáficas...
This work was done to determine the Neoproterozoic evolution of a southern Brasilia Fold Belt segment, Tapira area (SW Minas Gerais state), using detailed geologic mapping and structural metamorphic characterization. A complex structural evolution is deduced for these rocks and the main structure recognized is a low angle S4 foliation (N43W/30SE), associated with N50W/10 stretching and/or mineral lineation of the D4 phase. The S4 foliation is a crenulation cleavage, where the pre-existing S2 foliation was folded parallel to sedimentary bedding (S0). In some areas, S4 is a schistosity or a continuous cleavage. The S4 foliation also affects kilometric normal folds of the D3 phase. Two post-S4 groups of folds are recognized with low angle axes and high angle axial planes: D5 and D6 with axes in NW and N-S direction, respectively. Three transcurrent shear zones are associated with the D5 phase, dividing the area into three tectonic stratigraphic domains: Western, Eastern and Southern. Two thrust sheets separated by a thrust fault characterize the Western Domain (WD). Metapelitic rocks and graphite-bearing pelites with metapsammitic lenses represent the thrust sheet 1. A muscovite + quartz + garnet l chlorite l biotite l chloritoid l graphite l albite association defines the rocks of thrust sheet 1 as upper greenschist facies (garnet zone), with T = 540 ºC and P = 7.5 kbar conditions. At the top, thrust sheet 2 is characterized by metapelitic rocks and metapsammitic lenses and hornblende-bearing garnet-muscovite schists intercalations, with metamafic and metaultramafic rocks. The muscovite + quartz + garnet l hornblende l chlorite l biotite l oligoclase and the hornblende + oligoclase + biotite associations suggest amphibolite facies with a range of T= 585 to 610 ºC and P= 8 to 10 kbar. The Eastern Domain (ED) comprises three...(Complete abstract click electronic access below)
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Drover, David Howard. "Regional and detailed structural geology of the Quirk Creek structure, S.W. Alberta." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0017/MQ55203.pdf.
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Al-Kotbah, Ahmed Mohammed Abdullah. "Structural geology of South Hadhramaut area Yemen Republic." Thesis, University of Glasgow, 1996. http://theses.gla.ac.uk/1460/.
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The northern margin of the Gulf of Aden has a long history of extension from the Cambrian to the present. The dominant structures are related to Oligo-Miocene rifting in the early stages of development of the Gulf of Aden and they overprint Palaeozoic and Mesozoic structures. An area of 170 km by 50 km was mapped at scale of 1:50,000. Landsat images of the whole area, at 1:50,000 and 1:100,000 and air photographs of part of the area were used as base maps. The resulting maps are the first detailed geological maps to be made for this area and are a major outcome of this research. Precambrian basement which was affected by the oldest stage of extension is overlain by a sedimentary cover sequence from upper Cretaceous through the Tertiary in age. The lower part of this sequence represents the Mesozoic post-rift succession deposited after the second period of extension recorded in this margin. Oligo-Miocene extension has resulted in a highly dissected rift shoulder in which the horizontal cover sequence at an elevation of 1500m to 2500m on the plateau is brought down in a series of tilted fault blocks to sea level at the Gulf coast. The massive, nodular Palaeocene limestone of the Umm er Radhuma Formation forms steep inaccessible fault scarps throughout the area. The faults vary in size from major ones which have strike lengths in excess of 50 km and throws over 1000 m to those that are too small to be recorded on the maps. By measuring the geometry of bedding in the rollover anticlines in the hanging walls of selected faults, the trajectories of the faults at depths were computed. These show that the major faults extend steeply down into metamorphic basement. Major faults with kilometric throws must lie off-shore or, less likely, are buried beneath the syn- and post-rift sediments of the coastal plain.
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Kazadi, Banza Samuel-Barry. "Structural geology of the Kinsevere Copper Deposit, DRC." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/24753.
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The Kinsevere mine is a copper deposit located in the Democratic Republic of Congo (DRC), within the Central African Copperbelt. This area is situated in the Katangan basin within the SE portion of the Lufilian Arc, which is a large, arcuate structure that extends from SE Angola, across the DRC, and into NW Zambia. The purpose of this study is to characterise the brittle deformation observed around the Kinsevere copper deposit to lead to an understanding of the deformation history of the area. This is accomplished by analysing fault-slip and fold data to help understand the relationship between regional palaeostress, faulting and folding present in the mine vicinity. This study also attempts to characterise fracture-controlled copper mineralisation within the interpreted geodynamic context of the area. The broader objective of this study is to relate the structural observations from Kinsevere to the deformation history of the Lufilian Arc. This study uses the right dihedral method to analyse four categories of brittle structures. The structural types analysed include slickensided faults, mineralised joints, and unmineralised joints and shear fractures. The data suggests that the palaeostress associated with the formation of brittle structures in the Kinsevere area occurred during three deformation events. The first event is characterised by a compressional stress regime which occurred during the early stage of the Kolwezian phase (D1). The second event is characterised by a strike-slip stress regime that formed as the result of clockwise rotation of the earlier (D1) compressional regime. Two fault-slip vectors were observed on the strike-slip fault planes, indicating that a reactivation occurred during the Monwezian phase (D2). The final structural event was characterised by the development of an extensional stress regime. This was associated with North-South oriented extension and is related to the East African Rift System (D3). These interpreted events correlate well with the geodynamic context related to the Lufilian orogeny. Another line of evidence that supports this structural interpretation is the presence of evaporitic minerals observed in the stratigraphic units surrounding the brecciated zones such as the RAT and the CMN. The structural association of these evaporitic minerals may be related to pre-existing, salt-bearing units, which were dissolved during an early compressive (D1) phase of the Lufilian orogeny. However, the contact between the Grey RAT and the Red RAT (distal from the breccia zones) does not show any evidence of faulting, and in the Kinsevere area the Grey RAT is always observed above the Red RAT. This suggests that the Grey RAT may be the uppermost stratigraphic unit of the RAT subgroup, which contradicts some previously published interpretations. Thus, the current structural architecture was probably formed from a combination of two separate mechanisms, including compression-related salt extrusion and the development of thrust faults and folding resulting from the shortening of the Katangan basin. Based on an analysis of the fracture-controlled mineralisation in the study area, it is shown here that most of the stress tensors indicate that these fractures were induced within the compressional stress regime generated by the Lufilian orogeny. This conclusion supports studies which suggest a multiphase origin for the mineralizing fluids active in the Katangan basin. Thus, the age of the copper mineralisation associated with fractures is interpreted to correlate with the timing of the folding event that occurred during the Lufilian orogeny between 540-550Ma.Dissertation (MSc)--University of Pretoria, 2012.
Geology
unrestricted
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Rodriguez-Roa, Fernando Antonio. "Thrust belt architecture of the central and southern Western Foothills of Taiwan." Thesis, [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1523.
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Burgette, Reed Joel. "Uplift in response to tectonic convergence : the Kyrgyz Tien Shan and Cascadia subduction zone /." Connect to title online (ProQuest), 2008. http://proquest.umi.com/pqdweb?did=1616709721&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2008.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 225-242). Also available online in ProQuest, free to University of Oregon users.
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Thompson, Stephen C. "Active tectonics in the central Tien Shan, Kyrgyz Republic /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/6744.
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Seiler, Christina. "Structural and thermal evolution of the Gulf Extensional Province in Baja California, Mexico : implications for Neogene rifting and opening of the Gulf of California /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/4212.
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Henry, Heather Marie. "Investigation of a triangle zone structure between Augusta and Bowman's Corners, Lewis and Clark County, Montana." CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05212007-104742/.
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Elliot, Henry K. "Fractures in the region of the Rocky Hill anticline, Rocky Hill, Connecticut : a structural geological study /." View abstract, 2001. http://library.ccsu.edu/ccsu%5Ftheses/showit.php3?id=1644.
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Thesis (M.S.)--Central Connecticut State University, 2001.Thesis advisor: Charles W. Dimmick. " ... in partial fulfillment of the requirements for the degree of Master of Science in Physics and Earth Sciences." Includes bibliographical references (leaves 60-64). Also available via the World Wide Web.
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Copfer, Torrey J. "Geology of the Deseret Peak East 7.5' Quadrangle, Tooele County, Utah, and Impacts for Hydrology of the Region." DigitalCommons@USU, 2003. https://digitalcommons.usu.edu/etd/6723.
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Detailed geologic mapping of the Deseret Peak East 7.5' Quadrangle yields new interpretations regarding the stratigraphy of the Oquirrh Basin, fault and fold geometry, and structural evolution of the region. The Stansbury Range consists of the north-southtrending Deseret anticline. Basal Mississippian units rest unconformably on Cambrian beds in the central part of the range. Paleozoic uplift, Mesozoic contraction, and Cenozoic extension have created a series of broad folds, large thrust faults, and several normal faults.
The area is dominated by bedrock springs, with the presence of abundant and thick Quaternary deposits unrelated to Pleistocene glaciation, burying drainages, and mantling hillslopes. The influence of bedrock on groundwater flow paths and stream baseflow is suggested by local anecdotal reports that high snowfall in the Deseret Peak region generates high discharge ten miles south in Clover Creek, though they are not in the same drainage basin.
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Andrade, Frederico Guilherme Guaraldo de [UNESP]. "Lineações minerais em porfiroblastos." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/92881.
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andrade_fgg_me_rcla.pdf: 1229975 bytes, checksum: 09b1fccb568d0ad941d82c61d3c81d9f (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O estudo de lineações minerais tem fundamental importância na compreensão da evolução tectônica de cinturões orogênicos. Entretanto, em áreas polideformadas, enquanto as orientações das lineações mais novas podem ser resgatadas, as lineações antigas tendem a ser obliteradas pela superposição dos eventos deformacionais mais novos. Esta dissertação lança uma nova metodologia para o resgate da orientação de lineações minerais inclusas em porfiroblastos, utilizando a Platina Universal, além de testar a metodologia na Ilha Elefante, Antártica. Foi realizado um estudo teórico analisando o comportamento de lineação mineral, considerando-se variáveis como diferentes posições iniciais da lineação, diferentes morfologias de porfiroblastos, as possíveis relações temporais com o evento gerador da lineação, variados mecanismos de deformação e rotação (ou não) de porfiroblastos. A metodologia foi aplicada no estudo e leitura direta de lineações minerais em porfiroblastos da Ilha Elefante utilizando a Platina Universal, obtendo-se um padrão de orientação similar às medidas das mesmas estruturas em campo, provando a validade e viabilidade do método. A metodologia apresentada é de grande utilidade em áreas polideformadas, uma vez que contribui para a identificação da orientação dos paleovetores de stress.
The study of mineral lineations has been of fundamental importance in the comprehension of tectonic evolution in orogenetic belts. However, in polydeformated areas,, while the newest lineation’s orientation can be found, the oldest lineations tend to be obliterated by the newest deformation events. This thesis launches a new methodology to the rescue of mineral lineations’ orientation included within porphyroblasts, using the Universal Stage, and testing the methodology in the Elephant Island, Antarctica. It has been made a theorical study, analyzing the behavior of a mineral lineation, considering various hypothesis, like the initial position, different morphologies of porphyroblasts, the possible temporal relationships with the lineation’s generator event and various mechanisms of deformation and rotation (or not) of porphyroblasts. The methodology was applied in the study and direct measurement of mineral lineations in porphyroblasts of Elephant Island using the Universal Stage, obtaining an orientation pattern similar to the same structures in the field, proving the validity and viability of the method. The methodology presented is useful in polideformated areas, once that helps to identify the orientation of paleovectors of stress.
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Nogueira, Johnson Fernandes [UNESP]. "Estrutura, geocronologia e alojamento dos batólitos de Quixadá, Quixeramobim e Senandor Pompeu - Ceará central." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/103013.
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nogueira_jf_dr_rcla_prot.pdf: 5154714 bytes, checksum: 9c2ffc2d884cd3adbed2a96a48ec0737 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O Ceará Central caracteriza-se pela ocorrência de uma rede de zonas de cisalhamento preferencialmente orientada na direção NE-SW e/ou NNE-SSW. Associados espacialmente a estas zonas de cisalhamento ocorrem rochas intrusivas de dimensões variadas. Entre estas ocorrem os Batólitos de Quixeramobim, Quixadá e Senador Pompeu. Estes batólitos apresentam-se com forma alongada na direção NE-SW, subparalela às zonas de cisalharnento principais (Zonas de Cisalhamento de Senador Pompeu e Quixeramobim, por exemplo). O Batólito de Quixeramobim apresenta rochas agrupadas em seis diferentes fácies. As rochas desde batálito constituem uma série cálcio-alcatina granodiorítica, com dioritos predominantes e granitos 3A e quartzo-dioritos subordinados, ocupando a quase totalidade da área de ocorrência. O Batólito de Quixadá é composto por monzonitos e qz-monzonitos e o Batálito de Senador Pompeu por granodioritos e monzogranitos As características deformacionais, levantadas através de estudos das feições planares e lineares impressas nestas rochas, são sugestivas de um desenvolvimento progressivo em condições de estado magmático passando ao estado sálido, o que caracteriza as zonas de cisahamento principais como mobilizadoras de magmas e responsáveis pelo alojamento final das rochas. Datações radiométricas U-Pb e Pb-Pb forneceram idades de cristalização (alojamento) de 585 l 4,7 Ma (Quixadá), 587 l 14 Ma (Quixeramobim) e 561 l 15 Ma (Senador Pompeu). O mecanismo de alojamento sugerido para o Batólito de Quixadá compreende expulsão de magma de porções mais profundas para o local de alojamento final em regime transpressivo. Para os Batólitos de Senador Pompeu e Quixeramobim, sugere-se geração de espaço por nucleação de fraturas em extensão associada a transcorrência. Este último registrando variação de regime transtrativo para transpressivo.
The Central Ceará (NE Brazil) has, as typical characteristic, a shear zone system network with directions in NE-SW and for NNE-SSW. In association with these shear zones occur intrusive rocks like Quixeramobim, Quixadá and Senador Pompeu Batholiths. They have elongated shape in NE-SW direction, broadly parallel to major dextral ductile shear zones. The Quixeramobim Batholith has rocks grouped in six different facies, characterizing a calc-alkaline series with diorites as major rock types. Subordinated granite and quartzdiorites also occur. The Quixadá Batholith is formed by monzonite e and quartzmonzonite. The Senador Pompeu Batholith includes granodiorites and monzogranites. These rocks have foliaton and lineation organization pattern that are suggestive of progressive fabric development in magmatic and solid state. The orientation of these features is broadly parallel to the shear zones that promote emplacement of lhe plutons. U-Pb and Pb-Pb minimum emplacement ages are 585 l 4.7 Ma (Quixadá), 587 l 14 Ma (Quixeramobim) e 561 l 15 Ma (Senador Pompeu). The emplacement of the Quixadá Batholith mechanism suggested is the squeeze of magma from deeper places into lhe crust to the final emplacement site in trasnpression. For the Quixeramobim and Senador Pompeu Batholiths, we suggest an emplacement mechanism with space generation by fracture nucleation in extension, into the transcurente framework.
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Ferreira, Samuel Nunes. "Geologia estrutural aplicada às rochas ornamentais na Pedreira Knawa, Cláudio (MG) /." Rio Claro : [s.n.], 2004. http://hdl.handle.net/11449/92887.
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Resumo: Este trabalho apresenta os resultados de mapeamento geológico-estrutural de detalhe numa área piloto (Pedreira Knawa, Cláudio Estado de Minas Gerais) em escala de 1:200 e dos estudos de reconhecimento geológico em suas áreas adjacentes, e da aplicação do método de GPR na identificação de estruturas geológicas na Pedreira Knawa. Onde seu objetivo principal é proporcionar um direcionamento dos trabalhos geológico-estruturais na pedreira, visando otimizar a extração da rocha. As rochas que compõem esta região abrangem tanto rochas do complexo gnáissico-migmatítico de médio a alto grau denominado de Complexo Campo Belo quanto de suas supracrustais o Supergrupo Rio das Velhas, que encontram-se inseridos dentro do contexto geotectônico do Cráton do São Francisco Meridional. A Pedreira Knawa está localizada nos domínios da zona de cisalhamento Cláudio, e o arcabouço litológico predominante corresponde a um biotita gnaisse bandado fortemente migmatizado e deformado, de coloração cinza claro a cinza esbranquiçado, com pequenas quantidades de mobilizados félsicos de coloração rósea e xenólitos de rochas básica e ultrabásicas. As estruturas exibidas por esta rocha são predominantemente gnássica a migmatítica e revelam em escala de detalhe uma grande heterogeneidade, permitindo individualizar outros litotipos dentro deste arcabouço. Podem ser identificados da seguinte forma: biotita gnaisse bandado (rocha predominante), xenólitos de anfibolito e ultramafitos, granito, bandas dioríticas, veios pegmatíticos, zonas migmatíticas, veios migmatíticos de zonas de cisalhamento e diques de anfibolitos. A análise das feições estruturais e geológicas, observadas principalmente na área da pedreira e em seu entorno, permitiu identificar uma seqüência de três eventos geológicos estruturais principais, impressos nos gnaisses (Dn, Dn+1 e Dn+2), além da deposição...(Resumo completo, clicar acesso eletrônico abaixo)Abstract: The results of a detailed geologic-strutural mapping in the scale 1:200 are presented for a pilot area (Knawa quarry in the village of Cláudio, state of Minas Gerais). Geologic reconnaissance studies in adjacent areas and GPR surveys were performed to identify geologic structures. The main objective of those works was to guide geologic-structural mapping in the quarry to optimize production of dimension stones. The rocks in the region spam from the highly metamorphic Campo Belo composed of gneissic-migmatites to supracrustal Rio das Velhas supergroup in the geotectonic context of the southern São Francisco Craton. Knawa quarry is located in the domains of the Cláudio shear zone, where predominant lithology corresponds to a banded stronghy migmatized and deformed biotite gneiss showing ligh grey to whitish color, small felsic masses, pink in color and xenoliths of basic and ultrabasic rocks. These rocks predominantly exhibit gneissic to migmatitic structures but are very heterogeneous, allowing to individualise other lithotypes within the framework, as such: banded biotite gneiss (predominant) xenoliths of anfobolite and ultramafic rocks, granite, dioritic bands, pegmatitic veins migmatitic zones, migmatitic veins in shear zones and anfibolitic dykes. From the analysis of the structural and geologic features a sequence of structural events was identified, consisting of three main geologic events in the gneisses (Dn, Dn+1& Dn+2) plus the deposition deformation of the supracrustal and the intrusion of basic dykes. Evaluation and optimization of mining started from the identification of the geologic factors that affect production. These parameters were drawn from the assessment of the geologic map and of the commercial recovery deriving maps of optimized and three-dimensional geologic models. The volume calculation of the fifth level of the quarry identified a total volume of 33731, 28 m3, the volume of sectors with a recovery below 15% equal to.
Orientador: Luiz Sérgio Amarante Simões
Coorientador: João Carlos Dourado
Banca: Fábio Soares Magalhães
Banca: Antonio Carlos Artur
Mestre
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Silva, Carlos Humberto da. "Evolução geológica da faixa Brasília na região de Tapira, Sudoeste de Minas Gerais /." Rio Claro : [s.n.], 2003. http://hdl.handle.net/11449/103025.
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Orientador: Luiz Sérgio Amarante SimõesBanca: Rudolph Allard Johannes Trouw
Banca: Cláudio de Morrisson Valeriano
Banca: Hildor José Seer
Banca: Hans Dirk Ebert
Resumo: O presente trabalho apresenta uma proposta de evolução geológica Neoproterozóica de um segmento da Faixa Brasília Meridional, na região de Tapira (SW de Minas Gerais). A partir de mapeamento geológico detalhado é da caracterização estrutural e metamórfica. As rochas desta região apresentam uma complexa evolução estrutural, onde a principal estrutura reconhecida é uma foliação em baixo ângulo (S4) orientada em média N43W/30SE, à qual associa-se uma lineação de estiramento e/ou mineral orientada N50W/10, atribuídas à fase D4. A foliação S4 normalmente é reconhecida como uma clivagem de crenulação, cuja superfície crenulada é uma foliação S2, sub-paralela ao acamamento sedimentar (S0). Em alguns locais S4 manifesta-se como uma xistosidade ou clivagem contínua. A foliação S4 também afeta dobras normais de escala quilométrica relacionadas à fase D3. Adicionalmente são reconhecidos dois conjuntos de dobras pós-fase principal com eixos de caimentos suaves e planos axiais íngremes, sendo os eixos de D5 de direção NW e os eixos de D6 de direção NNE. Relacionada à fase D5 associam-se três zonas de cisalhamento transcorrentes quilométricas, a partir das quais sub-divididiu-se a área em três domínios tectono-estratigráficos. No domínio oeste (DW) ocorrem duas escamas tectônicas separadas por falha de empurrão. A escama 1 apresenta rochas metapelíticas e pelítico-grafitosas com intercalações psamítica. A associação mineral muscovita + quartzo + granada l clorita l biotita l cloritóide l grafita l albita, permitem situar as rochas dessa escama na fácies xisto verde superior (zona da granada), com condições de T e P estimadas em 540°C e 7,5 kbar. Na escama 2 predominam rochas pelíticas com intercalações psamíticas, adicionalmente ocorrem intercalações de hornblenda-granada-mica xistos e rochas metamáficas e metaultramáficas...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This work was done to determine the Neoproterozoic evolution of a southern Brasilia Fold Belt segment, Tapira area (SW Minas Gerais state), using detailed geologic mapping and structural metamorphic characterization. A complex structural evolution is deduced for these rocks and the main structure recognized is a low angle S4 foliation (N43W/30SE), associated with N50W/10 stretching and/or mineral lineation of the D4 phase. The S4 foliation is a crenulation cleavage, where the pre-existing S2 foliation was folded parallel to sedimentary bedding (S0). In some areas, S4 is a schistosity or a continuous cleavage. The S4 foliation also affects kilometric normal folds of the D3 phase. Two post-S4 groups of folds are recognized with low angle axes and high angle axial planes: D5 and D6 with axes in NW and N-S direction, respectively. Three transcurrent shear zones are associated with the D5 phase, dividing the area into three tectonic stratigraphic domains: Western, Eastern and Southern. Two thrust sheets separated by a thrust fault characterize the Western Domain (WD). Metapelitic rocks and graphite-bearing pelites with metapsammitic lenses represent the thrust sheet 1. A muscovite + quartz + garnet l chlorite l biotite l chloritoid l graphite l albite association defines the rocks of thrust sheet 1 as upper greenschist facies (garnet zone), with T = 540 ºC and P = 7.5 kbar conditions. At the top, thrust sheet 2 is characterized by metapelitic rocks and metapsammitic lenses and hornblende-bearing garnet-muscovite schists intercalations, with metamafic and metaultramafic rocks. The muscovite + quartz + garnet l hornblende l chlorite l biotite l oligoclase and the hornblende + oligoclase + biotite associations suggest amphibolite facies with a range of T= 585 to 610 ºC and P= 8 to 10 kbar. The Eastern Domain (ED) comprises three...(Complete abstract click electronic access below)
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Andrade, Frederico Guilherme Guaraldo de. "Lineações minerais em porfiroblastos /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/92881.
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Orientador: Luiz Sérgio Amarante SimõesBanca: Rudolph Allard Johannes Trouw
Banca: Antenor Zanardo
Resumo: O estudo de lineações minerais tem fundamental importância na compreensão da evolução tectônica de cinturões orogênicos. Entretanto, em áreas polideformadas, enquanto as orientações das lineações mais novas podem ser resgatadas, as lineações antigas tendem a ser obliteradas pela superposição dos eventos deformacionais mais novos. Esta dissertação lança uma nova metodologia para o resgate da orientação de lineações minerais inclusas em porfiroblastos, utilizando a Platina Universal, além de testar a metodologia na Ilha Elefante, Antártica. Foi realizado um estudo teórico analisando o comportamento de lineação mineral, considerando-se variáveis como diferentes posições iniciais da lineação, diferentes morfologias de porfiroblastos, as possíveis relações temporais com o evento gerador da lineação, variados mecanismos de deformação e rotação (ou não) de porfiroblastos. A metodologia foi aplicada no estudo e leitura direta de lineações minerais em porfiroblastos da Ilha Elefante utilizando a Platina Universal, obtendo-se um padrão de orientação similar às medidas das mesmas estruturas em campo, provando a validade e viabilidade do método. A metodologia apresentada é de grande utilidade em áreas polideformadas, uma vez que contribui para a identificação da orientação dos paleovetores de stress.
Abstract: The study of mineral lineations has been of fundamental importance in the comprehension of tectonic evolution in orogenetic belts. However, in polydeformated areas,, while the newest lineation's orientation can be found, the oldest lineations tend to be obliterated by the newest deformation events. This thesis launches a new methodology to the rescue of mineral lineations' orientation included within porphyroblasts, using the Universal Stage, and testing the methodology in the Elephant Island, Antarctica. It has been made a theorical study, analyzing the behavior of a mineral lineation, considering various hypothesis, like the initial position, different morphologies of porphyroblasts, the possible temporal relationships with the lineation's generator event and various mechanisms of deformation and rotation (or not) of porphyroblasts. The methodology was applied in the study and direct measurement of mineral lineations in porphyroblasts of Elephant Island using the Universal Stage, obtaining an orientation pattern similar to the same structures in the field, proving the validity and viability of the method. The methodology presented is useful in polideformated areas, once that helps to identify the orientation of paleovectors of stress.
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Massucatto, Armando José. "Caracterização estrutural do embasamento do Grupo Araí, na zona externa da faixa Brasília (GO) /." Rio Claro : [s.n.], 2003. http://hdl.handle.net/11449/103016.
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Orientador: Luiz Sergio Amarante SimõesBanca: Nilson Francisquini Botelho
Banca: Marco Antonio Fonseca
Banca: Norberto Morales
Banca: Hans Dirk Ebert
Resumo: A área de estudo, objeto desta tese de doutoramento, situa-se na porção nordeste do estado de Goiás, na região de Cavalcante. Nesta região são encontradas rochas do embasamento da Faixa de Dobramentos Brasília, composto por rochas do Complexo Granítico-gnáissico, mega veios de quartzo e Formação Ticunzal. Recobrindo estas rochas são visíveis os metassedimentos do Grupo Araí. As rochas do embasamento da Faixa de Dobramentos Brasília na área de estudo se apresentam fortemente deformadas, mostrando uma alta complexidade estrutural, o que indica que foram submetidas a diferentes eventos deformacionais. Para um melhor entendimento da evolução geólogica da área buscou-se através de diferentes técnicas e ferramentas a separação dos eventos deformacionais que atuaram sobre a região. Os trabalhos realizados levaram a identificação de 5 foliações distintas, sendo que as mesmas foram hierarquizadas e separadas, em função de sua geração, em 3 eventos deformacionais. Para refinar a separação destes eventos deformacionais foram realizadas datações em muscovitas pertencentes às respectivas foliações, utilizando-se o método 40Ar/39Ar. O Evento denominado genericamente de 1, apresenta uma foliação (S1) com direção próxima a EW, mergulho subvertical. Tal foliação é gerada como resposta a uma compressão de direção próxima a NS. As datações realizadas em micas brancas formadas durante este evento, indicam idades mínimas de 1.5 Ga. O Evento 2, decorrente de uma compressão de direção próxima a EW, é responsável pela geração de uma foliação (S2) com direção próxima a NS, que apresenta um mergulho vertical. Associa-se a esta fase uma lineação de estiramento em geral vertical e localmente de baixo ângulo. As datações realizadas apontam para idades mínimas de 1.4 Ga, para micas brancas geradas durante este evento...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract:The studied area in this PhD thesis is located in the northeast portion of Goias State, near Cavalcante Town. Basement rocks of Brasilia Fold Belt, composed basically by Granitic-Gneiss Complex, mega quartz veinz and the Ticunzal Formation, characterize this area. Overlying these rocks are the Araí Group Metassediments. The basement rocks of Brasilia Fold Belt, in the studied area, are strongly deformed, showing a highly structural complexity, which indicate these rocks were submitted by different deformational events. For a better understanding of geological evolution, different techniques and tools to distinguish the deformational events have been applied. The work done defined the identification of five different foliations, which were ordered and separated in three different deformational events because its generations. To refine its events separation, 40Ar/39Ar dating in muscovites belonging in each foliation has been done. The Event denominated generally by "1" presents an EW direction foliation (S1) with a sub vertical dipping. Such foliation was generated as consequence for an NS direction compression. The dating done in white micas formed during this event, yielded a minimum age of 1.5 Ga. The "Event 2", consequence of a close EW direction compression, generated a close NS direction foliation (S2) with vertical dipping. The white micas dating suggest a minimum age of 1.4 Ga for this event. Petrographic analysis indicated rocks that were submitted by the Events "1" and "2", were affected by similar metamorphism conditions, where might have reached temperatures between 450 and 500o C. The mega quartz veins possibly have been generated during the Event "2". Accomplished studies showing that its geometries are conformable with the cinematic aspects found in this event...(Complete abstract click electronic access below)
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Crowley, James L. Carleton University Dissertation Earth Sciences. "U-Pb geochronology in Frenchman Cap dome of the Monashee complex, southern Canadian Cordillera; early Tertiary tectonic overprint of a Proterozoic history." Ottawa, 1997.
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Bradway, Michael David. "Stratigraphy and structural geometry at the leading edge of the Montana Thrust Belt, east of Sun River Canyon, Lewis and Clark and Teton Counties, Montana." CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05072007-163806/.
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Brown, Hillary E. "Crustal rupture, creation, and subduction in the Gulf of California, Mexico and the role of gas hydrate in the submarine Storegga slide, offshore Norway." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1475164361&sid=10&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Van, Gestel Jean-Paul. "Structure and tectonics of the Puerto Rico-Virgin Islands platform and multi-confirguration ground penetrating radar data /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Doerr, John Timothy. "The structural controls of the Vale Rhinehart Buttes complex, Vale KGRA, Malheur County, Oregon." PDXScholar, 1986. https://pdxscholar.library.pdx.edu/open_access_etds/3585.
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The Vale KGRA is characterized by high heat flow, two to five times higher than the worldwide average, and by numerous hot springs. The hot springs are aligned along faults. This phenomena is typical of a Basin and Range type geothermal system. The hot geothermal fluids migrate upward along the more permeable, fault planes.
The rocks exposed in the Vale area are the Pliocene Chalk Butte formation and the Pleistocene beds of Captain Keeney Pass. Both units are composed of volcaniclastic siltstones, sandstones and conglomerates. The units are differentiated by color, texture and degree of lithification. About 200 meters of the Chalk Butte formation and 100 meters of the beds of Captain Keeney Pass are exposed in the area. Silicification is wide spread in the rocks of the Chalk Butte formation.
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Kampmann, Tobias Christoph. "3D structural framework and constraints on the timing of hydrothermal alteration and ore formation at the Falun Zn-Pb-Cu-(Au-Ag) sulphide deposit, Bergslagen, Sweden." Licentiate thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26483.
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The Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit, situated in the Palaeoproterozoic (1.9–1.8 Ga) Bergslagen lithotectonic unit in the south-western part of the Fennoscandian Shield, is one of the major base and minor precious metal sulphide deposits in Sweden. Host rocks to the deposit as well as the ores and altered rocks were metamorphosed and affected by heterogeneous ductile strain during the Svecokarelian orogeny the total duration of which was 2.0–1.8 Ga. These processes both reworked the mineral assemblages of the original hydrothermal alteration system and reshaped the structural geometry of the deposit, following formation of the ores and the associated hydrothermal alteration.In order to study primary geological and ore-forming processes at Falun, it is necessary firstly to investigate the nature of the tectonothermal modification. In this licentiate thesis, a three-dimensional modelling approach is used in order to evaluate geometric relationships between lithologies at the deposit. This study demonstrates the polyphase character (D1 and D2) of the strong ductile deformation at Falun. The major rock-forming minerals in the silicate alteration rocks are quartz, biotite/phlogopite, cordierite, anthophyllite, chlorite, and minor almandine and andalusite. On the basis of microstructural investigations, it is evident that these minerals grew during distinct periods in the course of the tectonic evolution, with major static grain growth between D1 and D2, and also after D2. Furthermore, the occurrence of F2 sheath folds along steeply south-south-east plunging axes is suggested as a key deformation mechanism, forming cylindrical, rod-shaped ore bodies which pinch out at depth. The sheath folding also accounts for the same stratigraphic level (footwall) on both the eastern and western sides of the massive sulphide ores. A major, sulphide-bearing high-strain zone defines a tectonic boundary at the deposit and bounds the massive sulphide ores to the north.The geological evolution in the Falun area involved emplacement of felsic sub-volcanic intrusive and volcanic rocks and some carbonate sedimentation; followed by hydrothermal alteration, ore formation and the intrusion of dykes and plutons of variable composition after burial of the supracrustal rocks. Secondary Ion Mass Spectrometry (SIMS) U-Pb (zircon) geochronology of key lithologies in and around the Falun base metal sulphide deposit indicates a rapid sequence of development of different magmatic pulses with individual age determinations overlapping within their uncertainties. The intense igneous activity, as well as the feldspar-destructive hydrothermal alteration and ore formation are constrained by two 207Pb-206Pb weighted average (zircon) ages of 1894 ± 3 Ma for a sub-volcanic host rock not affected by this type of alteration and 1891 ± 3 Ma for a felsic dyke, which cross-cuts the hydrothermally altered zone and is also unaffected by this alteration. All other ages, including the granitic plutonic rocks, fall in the interval between these ages.The lithological, structural and geochronological observations have implications for the environment and the conditions of ore formation at the Falun deposit. Several aspects argue for an ore system resembling a classic volcanogenic massive sulphide (VMS) system in terms of type of alteration, metal zonation, the pyritic character of massive sulphides and an inferred vent-proximal location in relation to the convection-driving magmatic system. The bowl-shaped, sub-seafloor feeder part of such a system might have served as an initial inhomogeneity in the strata for the later development of strong stretching along steep axes and sheath fold formation during ductile strain. Possible discordant relationships along the margins of the massive sulphide ores, coupled with the syn-magmatic, pre-tectonic timing of ore formation are in accordance with a general VMS-type model for the Falun base metal sulphide deposit. These results provide a compromise solution to the previous debate around two opposing models of strictly syn-genetic vs. epigenetic, post-deformational carbonate-replacement processes for ore formation at the deposit.The Falun pyritic Zn-Pb-Cu-(Au-Ag) sulphide deposit, situated in the Palaeoproterozoic (1.9–1.8 Ga) Bergslagen lithotectonic unit in the south-western part of the Fennoscandian Shield, is one of the major base and minor precious metal sulphide deposits in Sweden. Host rocks to the deposit as well as the ores and altered rocks were metamorphosed and affected by heterogeneous ductile strain during the Svecokarelian orogeny (2.0–1.8 Ga). These processes both reworked the mineral assemblages of the original hydrothermal alteration system and reshaped the structural geometry of the deposit, following formation of the ores and the associated hydrothermal alteration.In order to study primary geological and ore-forming processes at Falun, it is necessary firstly to investigate the nature of the strong tectonothermal modification. In this licentiate thesis, a three-dimensional modelling approach is used in order to evaluate geometric relationships between lithologies at the deposit. This study demonstrates the polyphase character (D1 and D2) of the ductile deformation at Falun. The major rock-forming minerals in the silicate alteration rocks are quartz, biotite/phlogopite, cordierite, anthophyllite, chlorite, and minor almandine and andalusite. On the basis of microstructural investigations, it is evident that these minerals grew during distinct periods in the course of the tectonic evolution, with major static grain growth between D1 and D2, and also after D2. Furthermore, the occurrence of F2 sheath folds along steeply south-south-east plunging axes is suggested as a key deformation mechanism, forming cylindrical, rod-shaped ore bodies which pinch out at depth. The sheath folding also accounts for the same stratigraphic level on both the eastern and western sides of the massive sulphide ores. A major, sulphide-bearing high-strain zone defines a tectonic boundary inside the deposit and bounds the massive sulphide ores to the north. A precursor to this zone can have played a central role as a metal-bearing fluid conduit during ore genesis, prior to reactivation of the zone in the ductile regime.The geological evolution in the Falun area involved emplacement of felsic volcanic and sub-volcanic rocks and some carbonate sedimentation, followed by ore formation and hydrothermal alteration as well as the intrusion of dykes and plutons of variable composition. U-Pb zircon geochronology of key lithologies in and around the Falun base metal sulphide deposit indicates a rapid sequence of development of different magmatic phases with individual age determinations overlapping within their uncertainties. The igneous activity is constrained between a zircon U-Pb concordia age of 1899 ± 7 Ma for a sub-volcanic host rock and a zircon 207Pb-206Pb weighted average age of 1891 ± 3 Ma for a felsic dyke, with all other reliable ages, including the quartz-rich plutonic rocks, falling in the interval between them. This interval also included the hydrothermal alteration and ore formation at Falun.It is suggested that the bowl-shaped, sub-seafloor feeder part of a high-sulphidation and Au-bearing volcanogenic massive sulphide ore system, with replacement of carbonates and (sub)-volcanic rocks, served as an initial inhomogeneity in the strata for the later development of strong stretching along steep axes and sheath fold formation during ductile strain. The observation of discordant relationships along the margins of the massive sulphide ores, coupled with the syn-magmatic, pre-tectonic timing of ore formation, corroborate this hypothesis, providing a compromise solution to the previous debate around two opposing models of strictly syn-genetic vs. epigenetic, post-deformational carbonate-replacement processes of ore formation at the Falun base metal sulphide deposit.
Godkänd; 2015; 20150212 (tobkam); Nedanstående person kommer att hålla licentiatseminarium för avläggande av teknologie licentiatexamen. Namn: Tobias Christoph Kampmann Ämne: Malmgeologi/Ore Geology Uppsats: 3D Structural Framework and Constraints on the Timing of Hudrothermal Alteration and Ore Formation at the Falun Zn-Pb-Cu-(Au-Ag) Sulphide Deposit, Bergslagen, Sweden Examinator: Professor Pär Weihed Institutionen för samhällsbyggnad och naturresurser, Avdelning Geovetenskap och miljöteknik, Luleå tekniska universitet Diskutant: Docent, adjungerad professor Pietari Skyttä, University of Turku, Department of Geography and Geology, Turun Yliopisto, Finland Tid: Torsdag 23 april 2015 kl 10.00 Plats: F531, Luleå tekniska universitet
Structural evolution, hydrothermal alteration and tectonic setting of the Falun base metal and gold deposit, Bergslagen region, Sweden
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Pearson, Ofori. "Structural evolution of the central Nepal fold-thrust belt and regional tectonic and structural significance of the Ramgarh thrust." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/280143.
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Tectonic shortening within the Himalayan fold-thrust belt in Nepal has been accommodated by southward displacement of large thrust sheets. Most workers focus on the impact that the Main Central, Main Boundary, and Main Frontal thrusts have had on the orogen's structural, thermal, and geomorphic evolution. However, mapping across Nepal, has revealed the presence of the Ramgarh thrust, which is another orogen-scale thrust. The Ramgarh thrust, which had previously been recognized in India and far-western Nepal, occurs within Lesser Himalayan zone rocks, and accommodates a magnitude of shortening similar to that of the Main Central thrust. This dissertation focuses on the structural and tectonic significance of the Ramgarh thrust. Minor details notwithstanding, the structural characteristics of the Ramgarh thrust remain consistent along the ∼800 km width of the fold-thrust belt in Nepal. At current levels of erosion, the Ramgarh thrust is always exposed in a hanging-wall flat on footwall flat thrust relationship with other Lesser Himalayan zone rocks, and also with overlying rocks carried by the Main Central thrust. Mapping along a north-south transect in central Nepal has permitted the construction of a balanced cross-section, which shows that the fold-thrust belt has accommodated a minimum of 489 km of tectonic shortening. A large proportion of which was accommodated by slip on the Ramgarh thrust. Integrating structural constraints provided by mapping and the cross-section with existing thermochronologic, thermobarometric, and foreland basin provenance datasets yields a kinematic model for the structural evolution of the fold-thrust belt. Recognition of the structural relationship between the Ramgarh and Main Central thrusts also permits new insight into the nature of the Main Central thrust. Structural mapping combined with Nd isotope studies from the vicinity of the Ramgarh and Main Central thrusts in Langtang National Park suggest that the Main Central thrust can be defined as a relatively narrow tectonostratigraphic contact, and not as a broad, poorly defined, shear zone. Additionally, much of the volume of highly strained rocks in the footwall of the Main Central thrust may be genetically related to deformation on faults (including the Ramgarh thrust) that lie structurally below the Main Central thrust.
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Isler, Ekrem Bursin. "Late quaternary stratigraphic and tectonic evolution of the northeastern Aegean Sea /." Internet access available to MUN users only, 2005. http://collections.mun.ca/u?/theses,147122.
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Hayman, Nicholas W. "Structure and petrology of gouge and breccia bearing shallow crustal shear zones of detachment faults in Death Valley, California /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6699.
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Dunham, Rachel E. Crider Juliet G. "Kink band development in the Darrington Phyllite on Samish Island, northwestern Washington /." Online version, 2010. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=367&CISOBOX=1&REC=14.
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Hill, Joseph Christopher. "Structural geology and tectonics of the paleoproterozoic rocks of the Mount Rushmore Quadangle, Black Hills, Souh Dakota." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4456.
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Thesis (Ph.D.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (April 26, 2007) Vita. Includes bibliographical references.
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Bayliss, Brian G. Cronin Vincent S. "Test of a method for recognizing unmapped seismogenic faults." Waco, Tex. : Baylor University, 2007. http://hdl.handle.net/2104/5035.
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Luo, Hongjun. "Tectonostratigraphy of foreland basins the Upper Cretaceous in southwestern Wyoming /." Laramie, Wyo. : University of Wyoming, 2005. http://proquest.umi.com/pqdweb?did=990280521&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Douds, Ashley S. B. "Fractal analysis of topography and structure across the Appalachian foreland of West Virginia." Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=146.
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Thesis (M.S.)--West Virginia University, 1998.Title from document title page. Document formatted into pages; contains ix, 120, 102, 48, 2, 381, 377 p. : ill., maps (some col.). Includes abstract. Includes bibliographical references (p. 104-106).
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Kronsell, Ida. "Structural control on the Peña del Seo tungsten-greisen vein deposit, northwest Spain." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-76402.
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Tungsten is listed on the European Commission list of critical raw materials that are crucial to Europe’s economy. By raising awareness of tungsten as a critical raw material the EU can prioritise to enhance exploration, mining and recycling of tungsten. In this thesis the structural relationship between wall rock and veins, in a greisen-tungsten vein deposit, were analysed with the intention to interpret how tectonic deformation events control the emplacement of tungsten-bearing veins. The objective of this thesis is to investigate if and how structures controlled hydrothermal fluid flow and ore formation in the Peña del Seo tungsten-greisen vein deposit. Greisen systems are associated with tin and tungsten-bearing minerals and are related to intrusive magmatic bodies of granitic composition. Greisen-related granites (leucogranites), form at shallow depths in the crust (1.5-4 km) generally in intracontinental tectonic settings such as orogenic belts. The study site is located in the West Asturian-Leonese Zone in northwest Spain. This zone marks the transition between the foreland and the hinterland and is recognized as being part of a continental margin, where Palaeozoic rocks were deposited unconformably. These rocks were subsequently subjected to folding during the Variscan orogeny (370-290 Ma). Three main types of structures were generated due to three deformational phases (D1, D2 and D3) during the Variscan orogeny. D1 resulted in east-verging recumbent folding and formation of a related axial-planar parallel cleavage (S1), D2 resulted in displacement along large thrust sheets and D3 produced upright folding and refolding of F1 folds. Geological mapping with a focus on structural geology was carried out in March 2019, covering an area of approximately 0.25 km2. Structural measurements and oriented rock samples for microstructural study in thin sections were collected in the field. Additionally, photogrammetric mapping of structures was performed on a 3D photogrammetry model derived from a UAS survey. The geometry of the Peña del Seo tungsten-greisen vein deposit is interpreted to result from two major deformation events. The axial planar foliation (S1) at Peña del Seo is correlated to the regional fabric that developed during D1 of the Variscan orogeny. The related F1 folds are caused by buckling accompanied by flexural slip folding mechanism during D1. Forceful intrusion of the granite underlying the Peña del Seo deposit caused bending of the overlying rocks layers during D2. Layer-parallel stretching is likely to have caused tension fractures perpendicular to bedding in the outer arc of the F2 fold hinge. The formation of local crenulation and related spaced cleavage can be explained by layer-parallel shortening in the inner arc of the F2-fold. Local transposition of S1-foliation occurred during emplacement of quartz veins and explains the different orientation of strike of foliation between the northern and southern parts of the area. Fractures forming during formation of F2-fold are likely to have worked as conduits for ascending hydrothermal, ore-bearing fluids forming the Peña del Seo tungsten-greisen vein deposit.
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Johnson, Shannon D. "Structural geology of the Usakos Dome in the Damara Belt, Namibia." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50457.
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Thesis (MSc)--Stellenbosch University, 2005.ENGLISH ABSTRACT: The northeast-trending south Central Zone (sCZ) of the Pan-African Damara belt in central Namibia is structurally characterized by kilometer-scale, northeast-trending dome structures developed in Neoproterozoic rocks of the Damara Sequence. A number of different structural models have been proposed for the formation of these domes in the literature. This study describes the structural geology of the Usakos dome. The study discusses the structural evolution of the dome within the regional framework of the cSZ that represents the high-grade metamorphic axis of the Damara Belt, characterized by voluminous Pan-African granitoids. The northeastern part of the Usakos dome is developed as an upright- to northwestverging anticlinorium containing a steep southeasterly-dipping axial planar foliation. The northeast fold trend persists into the southwestern parts of the Usakos dome. However, this southwestern core of the dome is inundated by synkinematic granitic sheets. Distinct marker horizons of the Damara Sequence outcrop as screens within the granite, preserving a ghost stratigraphy. These screens illustrate the position and orientation of second-order folds. Significantly, most of the stratigraphy of the Damara Sequence is overturned in these folds. For example, some second-order anticlines developed in the northeastern parts of the Usakos dome can be followed along their axial traces into the southwestern hinge of the dome, where they appear as synformal anticlines, i.e. synformal structures cored by older strata, plunging towards the northeast. The inverted stratigraphy and northeasterly fold plunges suggest the northeast-trending folds are refolded by second-generation, northwest-trending folds, thus, forming kilometer-scale Type-2 interference folds. The resulting fold geometries are strongly non-cylindrical, approaching southwest-closing sheath folds indicating a top-to-the-southwest material transport. Lower-order folds in this overturned domain show radial fold plunges, plunging away from the centre of the dome core, as well as a shallowly-dipping schistosity. The close spatial and temporal relationship between granite intrusion and the formation of the southwest-vergent, sheath-type folds, radial distribution of fold plunges and the subhorizontal foliation confined to the southwestern hinge of the Usakos dome are interpreted to signify the rheological weakening and ensuing collapse of the developing first-order Usakos dome immediately above the synkinematic granite intrusions. Orogenparallel, southwest-vergent sheath folds and top-to-the southwest extrusion of the southwestern parts of the Usakos dome and northwest-vergent folding and thrusting characterizing the northeastern extent of the Usakos dome are both responses to the northwest-southeast- directed contractional tectonics recorded during the main collisional phase in the Damara belt. On a regional scale, the Usakos dome represents the link between the foreland-vergent northeastern part of the sCZ and the southwest-vergent, high-grade southwestern parts of the sCZ. The results of this study illustrate how dramatic variations in structural styles may be caused by the localized and transient rheological weakening of the crust during plutonic activity.
AFRIKAANSE OPSOMMING: Die noordoos-strekkende, suidelike Sentrale Sone (sSS) van die Pan-Afrikaanse Damara gordel in sentraal Namibië word karakteriseer deur kilometer-skaal, noordoosstrekkende koepel strukture, ontwikkel in die Neoproterozoïkum gesteentes van die Damara Opeenvolging. 'n Aantal verskillende struktuur modelle is voorgestel in die literatuur vir die vorming van hierdie koepels. Hierdie ondersoek beskryf die struktuur geologie van die Usakos koepel. Die ondersoek bespreek die strukturele ontwikkeling van die koepel in die regionale konteks van die sSS, wat die hoë graadse metamorfe magmatiese as van die Damara Gordel verteenwoordig, en karakteriseer word deur omvangryke Pan-Afrikaanse granitoïede. Die noordoostelike gedeelte van die Usakos koepel is ontwikkel as 'n antiklinorium met 'n vertikale- tot noordwestelike kantelrigting. wat 'n steil hellende, suidoostelike asvlak planêre foliasie bevat. Die noordoos-strekkende plooiing kom voor tot in die suidwestelike kern van die Usakos wat ingedring is deur sinkinematiese granitiese plate. Die posisie en oriëntasie van tweede-orde plooie is afgebeeld in die graniete deur 'n skimstratigrafie wat preserveer is deur duidelike merker horisonne van die Damara Opeenvolging. Die stratigrafie van die Damara Opeenvolging is opmerklik meestal omgekeer in hierdie plooie. Byvoorbeeld, tweede-orde antikliene ontwikkel in die noordoostelike gedeelte van die Usakos koepel kan gevolg word langs hul asvlakspore tot in die suidwestelike skarnier van die koepel, waar dit voorkom as sinforme antikliene, d.w.s. sinforme strukture met ouer strata in die kern wat na die noordooste duik. Die omgekeerde stratigrafie en noordoostelike plooi duiking impliseer dat die noordoosstrekkende plooie weer geplooi is deur tweede-generasie, noordwes-strekkende plooie, wat dus aanleiding gegee het tot die vorming van kilometer-skaal, tipe-2 interferensie plooie. Die gevolglike plooi geometrieë is uitdruklik nie-silindries, en toon 'n oorgang na skede plooie met 'n sluiting na die suidweste, wat dui op 'n bokant-na-die-suidweste materiaal vervoer. Laer-orde plooie in die omgekeerde domein vertoon radiale duiking van die plooie, weg van die middelpunt van die koepel kern, sowel as 'n vlak hellende skistositeit. Die noue ruimtelike en temporele verwantskap tussen graniet intrusie en die vorming van skede-tipe plooie met 'n kantelrigting na die suidweste, die radiale verspreiding van plooi duiking, en die subhorisontale foliasie wat beperk is tot die suidwestelike skarnier van die Usakos koepel, word interpreteer as 'n aanduiding van die reologiese verswakking en die gevolglike ineenstorting van die ontwikkelende eerste-orde Usakos koepel, onmiddellik aan die bokant van die sinkinematiese graniet intrusies. Die orogeenparalleie skede plooie met kantelrigting na die suidweste en bokant-na-die-suidweste ekstrusie van die suidwestelike gedeelte van die Usakos koepel, en plooiing met kantelrigting na die noordweste en stootverskuiwing wat kenmerkend is van die noordoostelike gedeelte van die Usakos koepel, is beide 'n reaksie op die noordwessuidoos- gerigte vernouings tektoniek opgeteken gedurende die hoof botsings fase in die Damara gordel. Op 'n regionale skaal verteenwoordig die Usakos koepel die verbinding tussen die noordoostelike gedeelte van die sSS met 'n voorland kantelrigting. en die hoë graad suidwestelike gedeelte van die sSS met 'n kantelrigting na die suidweste. Die resultate van hierdie ondersoek toon aan hoe dramatiese variasies in struktuur style veroorsaak kan word deur die gelokaliseerde en kortstondige reologiese verswakking van die kors gedurende plutoniese aktiwiteit.
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Nushart, Nathan. "Modeling Intrusive Geometries of a Shallow Crustal Intrusion: New Evidence From Mount Ellsworth, Utah." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5753.
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Surface displacements resulting from upper-crustal intrusion of melt are a paramount concern for communities and facilities located in or near active volcanic areas (e.g. Campi Flegrei, Yucca Mtn.). Study of active intrusions such as Campi Flegrei, Italy west of Mt. Vesuvius, is limited to remote observations through geophysical/geodetic procedures. While the surface displacement due to melt emplacement at depth can easily be determined, the geometries and depth of intrusions are often based on simplified assumptions (e.g. spheres and prolate or oblate ellipsoids). These models benefit from data constraining both the geometries of the individual intrusions, and the kinematics and mechanics of deformation within the superstructure overlying the intrusions. Mount Ellsworth, a partially exposed sub-volcanic system, is an ideal natural laboratory for the study of near surface intrusions. The intrusions of the Henry Mountains are ideal because they were emplaced into relatively flat-lying stratigraphy of the Colorado Plateau, at a time when the stress field was largely isotropic. Previous geologic work done in the Henry Mountains, conducted by C.B. Hunt (1953) and Marie Jackson and Dave Pollard (1988), presents competing emplacement models (i.e. large batch intrusion or incremental sill growth), as well as, differing geologic map data and interpretations. Through a combination of 1:5000 scale field mapping and profile-oriented gravity study, we have produced detailed geologic maps and cross sections of Mt. Ellsworth assess the previous work done on Mt. Ellsworth with new datasets, as well as, evaluate criteria refining various emplacement models. Mapping results demonstrate that several of the assumptions made in models theorized by Hunt (1953) and Jackson and Pollard (1988), were inappropriately applied on Mt. Ellsworth. These assumptions include the thickness and separation of stratigraphic units, the size and distribution of sills and smaller intrusions, structural attitudes of beds and sills, and the presence of exposure of the main body of the intrusion. Gravity data collected on similar intrusions presented in Corry (1988) demonstrates the difficulty of obtaining a gravity anomaly on the wavelength of the assumed size of the intrusion. Forward gravity modeling of various potential geometries beneath Mount Ellsworth suggests that the anomalies are similar in shape with a magnitude between 16 and 20 mGal. Results from the gravity profiles collected for this study fail to predict an anomaly on the wavelength of the Mount Ellsworth intrusion and record a much more complicated anomaly than is presented by the forward models. By combining the stratigraphic data, structural data, and cross sections, it can be determined that the Mount Ellsworth intrusion is a laccolith with a floor 1.5 kilometers beneath the topographic surface, is 1 kilometer thick at its maximum, and has dimensions of 4 kilometers wide by 6 kilometers long.