Dissertations / Theses: 'Apatite fission tracks'

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RESENTINI, ALBERTO. "Quantitative provenance analysis of modern sands: bulk petrography, heavy minerals apatite fission tracks." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2011. http://hdl.handle.net/10281/19000.

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Sediment petrography and heavy mineral analysis represent two key techniques to decipher the pieces of information stored in the sedimentary record, shedding light on source rocks compositon, weathering conditions and paleodrainages. Traditionally, even though orogenic detritus has always received large attention, orogenic provenance has been recognized as “composite”, thus preventing clear classification. Notwithstanding the composite nature of collision orogens, the detrital fingerprints of neometamorphic axial belts, largely experiencing strong exhumation and erosion, can be regarded as the diagnostic signature of orogenic detritus. We thus decided to focus our attention on the analysis of modern river sands from the Alpine belt, getting full quantitative information both on bulk compositions and heavy mineral assemblages. Within the Austroalpine Cretaceous and Penninic Eocene axial belts of the Alps, we ideally distinguish three structural levels, each characterized by diagnostic detrital fingerprints. The shallow level chiefly consists of offscraped remnant-ocean turbidites and unmetamorphosed continental-margin sediments, and mostly produces lithic to quartzolithic sedimentaclastic sands yielding very-poor heavy-mineral suites including ultrastable minerals. The intermediate level includes low-grade metasediments and polymetamorphic basements, and sheds quartzolithic to feldspatholithoquartzose metamorphiclastic sands yielding moderately-rich epidote-amphibole suites with chloritoid or garnet. The deep level contains eclogitic remnants of continent-ocean transitions, and supplies feldspatholithoquartzose/feldspathoquartzose high-rank metamorphiclastic to lithic ultramaficlastic sands yielding rich to extremely-rich suites dominated by garnet, hornblende, or epidote depending on protoliths (continental vs. oceanic) and pressure/temperature paths during exhumation. Although widely overprinted under greenschist-facies or amphibolite-facies conditions, occurrence of ultradense eclogite in source areas is readily revealed by the Heavy Mineral Concentration (HMC) index, which mirrors the average density of source rocks in the absence of hydraulic-sorting effects. Rather than the pressure peak reached at depth, the Metamorphic Index (MI) and Hornblende Colour Index (HCI) reflect peak temperatures reached at later stages, when subduction is throttled by arrival of thicker continental crust and geothermal gradients increase, as documented in detritus derived from the Tauern window and Lepontine dome. Experience gained from modern sediments, and appropriate statistical techniques provides fundamental help to decrypt the information stored in the sedimentary record, and thus to identify and reconstruct subduction events of the past. Besides the fundamental contribution that modern sediment analysis can bring in understanding ancient sandstone successions, it can also give insights on short-term erosion distribution over wide areas and readily detect potential area of focused erosion. We tested a new quantitative approach based on the integration of compositional data and detrital apatite fission-tracks in two valleys of the western Alps (Arc and Dora Baltea basins). Samples for bulk-petrography and fission-track analysis were collected at different closure sections along the trunk, in order to investigate how the detrital signal evolves when detritus from different sub-basins is progressively added to the system. Fission-track analysis is a powerful integration tool to quantify sediments mixing if source areas experienced contrasting exhumation paths. Fission-track grain-age distributions provide not only information on long-term exhumation patterns, based on the age of the peaks, but also provide first-order constraints on short-term erosion rates by comparison between the size of the peaks and the size of potential source areas. In the Dora Baltea catchment, the apatite load derives from two major fault-bounded blocks, the Western one yielding 43% of the total amount of apatite, and the Eastern one yielding the remaining 57%. In the Arc catchment, contribution is 29% from the Eastern Block, 14% from the Houiller-Subbriançonnais units and 57% from the Belledonne-Dauphinois units. We assessed apatite fertility in source-rocks by measuring apatite content in processed sediments, after checking for anomalous hydraulic concentrations by geochemical analyses. The lack of compositional anomalies for elements between Y and Cr, largely hosted in ultradense minerals, grants that source-rocks distribution in the basin is faithfully reflected by detrital assemblages. Results demonstrate that erosional processes were focused in different areas of the Western Alps at long-term and short-term timescales, and are now concentrated in the External Massifs. No clear relationship between erosion and climate or relief is observed in this sector of the belt, where endogenic forces may represent the main controlling factor on both long-term and short-term erosion rates.

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Meresse, Florian. "Dynamique d’un prisme orogénique intracontinental : évolution thermochronologique (traces de fission sur apatite) et tectonique de la Zone Axiale et des piémonts des Pyrénées centro-occidentales." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20038.

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Ce travail de thèse concerne une transversale complète des Pyrénées centro-occidentales, où on a combiné la thermochronologie basse température (traces de fission sur apatites, TFA) avec une analyse structurale détaillée pour décrire les mouvements verticaux associés à l'évolution du système chevauchant, et pour déterminer l'influence de ce dernier sur le cycle sédimentation/enfouissement/exhumation des dépôts synorogéniques du bassin d'avant-chaine sud (bassins de Jaca et Ainsa). L'analyse TFA complète les données déjà publiées dans la Zone Axiale et la Zone Nord-Pyrénéenne, et constitue la première étude de ce genre dans un bassin d'avant-chaîne pyrénéen. Les données TFA sur la transversale du bassin sud-pyrénéen montrent une diminution vers le sud du degré d'effacement des traces de fission, traduisant la diminution vers le sud de la quantité d'enfouissement, supérieure à 5 km au nord et inférieure à 3 km au sud dans l'hypothèse un géotherme de 25°.km-1. Le contexte géologique montre que l'enfouissement est principalement lié à l'accumulation des dépôts synorogéniques. Les données TFA de la partie nord du bassin montrent un refroidissement d'âge Oligocène supérieur-Miocène inferieur (moyen). Par ailleurs, une nouvelle interprétation de profils de sismiques réflexion dans le bassin de Jaca montre que le chevauchement d'Oturia s'enracine dans le chevauchement de socle de Bielsa, responsable de l'exhumation tectonique hors-séquence du bord sud de la Zone Axiale au Miocène inférieur (-moyen) (Jolivet et al., 2007). Ces résultats attestent donc de l'exhumation tectonique hors-séquence au Miocène inférieur (Burdigalien- ?Langhien) de la partie nord du bassin d'avant-chaine sud-pyrénéen. Des données TFA obtenues dans la Zone Axiale et la Zone Nord-Pyrénéenne confirment la migration générale vers le sud du système chevauchant, et mettent également en évidence la réactivation tectonique hors-séquence du bord nord de la Zone Axiale à l'Oligocène terminal-Miocène inférieur. L'ensemble de ces résultats atteste donc de la réactivation en « pop-up » de la parties interne des Pyrénées centre-ouest à l'Oligocène supérieur-Miocène inférieur (Burdigalien- ?Langhien), postérieurement au scellement du front sud-pyrénéen (Aquitanien- ?Burdigalien) classiquement considéré comme marquant la fin de la compression pyrénéenne. Ces données nous ont permis de proposer un nouveau modèle d'évolution crustale des Pyrénées centro-occidentales en 3 grandes étapes : (i) du Crétacé supérieur à l'Eocène moyen, le prisme est caractérisé par une absence de relief, en lien avec l'inversion de structures extensives crétacées conduisant à l'accrétion de petites écailles crustales ; (ii) la période Eocène supérieur-Oligocène correspond à la collision continentale proprement dite, et est marquée par la création d'importants reliefs associés à l'accrétion d'épaisses unités crustales ; (iii) au Miocène inférieur, la partie interne du prisme pyrénéen est réactivée
In this work on a complete transect of the west-central Pyrenees, we combine low temperature thermochronology (apatite fission tracks, AFT) with a detailed structural analysis to describe vertical movements related to the thrusting system evolution, and to determine the influence of the latter on the sedimentation/burial/exhumation cycle of the synorogenic deposits of the southern foreland basin (Jaca and Ainsa basins). AFT analysis from a transect of the south-Pyrenean basin show the southward decrease of the fission track reset level from the southern edge of the Axial Zone to the South-Pyrenean frontal thrust, implying the southwards decrease of the burial amount from more than 5km in the north to less than 3km in the south assuming an average geothermal gradient of 25°C.km-1. The structural setting of the Jaca basin attests that the burial of the synorogenic sediments was mainly due to the sedimentary accumulation. AFT data from the northern part of the basin display a late Oligocene-early (middle) Miocene cooling event. New interpretation of industrial seismic reflection profiles across the Jaca basin suggests that the Oturia thrust is rooted in the Bielsa basement thrust, responsible for the early (-middle) Miocene out-of-sequence tectonic reactivation of the southern flank of the Axial Zone (Jolivet et al., 2007). These results reveal a lower Miocene (Burdigalian -?Langhian) out-of-sequence episode of tectonic activity of the interior of the south-Pyrenean foreland basin. AFT data from the Axial Zone and the North-Pyrenean Zone confirm the general southward migration of the thrusting system, and also bring evidence of the late Oligocene-lower Miocene out-of-sequence tectonic reactivation of the northern flank of the Axial Zone. All these results attest of a late Oligocene-lower Miocene (Burdigalian-?Langhian) 'pop-up' reactivation of the inner part of the west-central Pyrenees, younger than the sealing of the south-Pyrenean front (Aquitanian-?Burdigalian) which is classically considered to mark the end of the Pyrenean compression. These results lead us to propose a new crustal scale evolution model of the west-central Pyrenees in 3 stages: (i) From the Late Cretaceous to the middle Eocene, the orogenic prism is characterised by the absence of relief, related to the inversion of Cretaceous extensional structures leading to the accretion of thin crustal units; (ii) The late Eocene-Oligocene stage corresponds to the continental collision, marke d by the creation of important relief associated with the accretion of thick crustal units; (iii) During the early Miocene, the inner part of the Pyrenean wedge is tectonically reactivated

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D'ADDA, PAOLO. "Eo-alpine evolution of the central southern alps. Insights from structural analysis and new geochronological constraints." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2011. http://hdl.handle.net/10281/19018.

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The timing of the Alpine deformation in the Central Southern Alps (CSA or Orobic Alps) has always been a debated topic, since the scarcity of reliable absolute age constraints has prevented an accurate chronological reconstruction of the evolution of this sector of the European Alps. In this work, detailed structural analyses performed in different areas of the CSA allowed us to distinguish different compressive features within both the crystalline basement and the sedimentary cover. The integration of these field data with new isotopic data provides time constraints for the reconstruction of the evolution of the CSA during the Alpine orogeny. In the northern sector of the belt a Variscan polymetamorphic basement is stacked southward on the Permian to Mesozoic cover along two main regional faults (Orobic and Porcile thrusts). Fault zones, slightly postdating a first folding event of Alpine age (D3), experienced a complex evolution through the ductile and brittle deformation regime, showing greenschists facies mylonites overprinted by a penetrative cataclastic deformation (D4). Generation of fault-related pseudotachylytes marks the onset of brittle conditions, lasting up to the youngest episodes of fault activity. Thrusting along this structures also produced thrusting within the Permian-Triassic cover with the formation of different south-verging thrust stacks. This first thrusting event was followed by the activation of new deeper thrust surfaces leading to the emplacement of three regional anticlines (Orobic Anticlines) which tilted to the south the previously stacked units. During this long compressive stage (Orobic-Porcile thrusts and Orobic Anticlines) the sedimentary cover of the CSA was also involved in thrusting and different stacks of Mesozoic units were emplaced to the south. 40Ar/39Ar dating of the pseudotachylyte matrix of 9 samples from both the Orobic and Porcile thrusts give two separated age clusters: Late Cretaceous (80-68 Ma) and Early to Middle Eocene (55-43 Ma). These new data provide evidence that the pre-Adamello evolution of the CSA was characterized by the superposition of different tectonic events accompanying the exhumation of the deepest part of the belt through the brittle-ductile transition. The oldest pseudotachylyte ages demonstrate that south-verging regional thrusting in the CSA was already active during the Late Cretaceous, concurrently with both the HP metamorphism that affected the Austroalpine units of the eastern Alps, and the development of a syn-orogenic foredeep basin where the Upper Cretaceous Lombardian Flysch was deposited. In the Early to Middle Eocene a minor reactivation of the Orobic and Porcile thrusts occurred, as testified by the youngest pseudotachylyte ages obtained by 40Ar/39Ar dating. This event was probably related with the closure of the Ligurian-Piedmont and the ongoing of the Europe-Adria collision. South of the Orobic Anticlines system the Triassic sedimentary succession is stacked into several units bounded by south-verging low-angle thrust faults, which are related to different steps of crustal shortening. Different thrust stacks occur within the Triassic cover between the Como Lake to the west and the Adamello batholith to the east. They usually have an antiformal arrangement and are separated by each other by different N-S trending transverse zones, such as the poorly known Grem-Vedra Transverse Zone (GVTZ), formed during complex deformational phenomena in a transpressional regime coeval with thrust emplacement. The GVTZ formed during the southward imbrication of the older thrust sheets of the Menna-Arera group, strongly interacting with syn-thrust ductile structures, and was reactivated during the growth of the Orobic Anticlines belt. The GVTZ and other transverse zones of the CSA probably reflect the occurrence of pre-existing fault systems that characterize the Norian to Jurassic rifting history of the Lombardian basin, and were reactivated as strike-slip features during Alpine tectonics. In the Gandino and Presolana areas thrust surfaces are cut by high-angle extensional and strike-slip faults, which controlled the emplacement of hypabissal magmatic intrusions that post-date thrusts motions. Intrusion ages based on SHRIMP U-Th-Pb zircon dating span between 42±1 and 39±1 Ma, suggesting close time relationships with the earliest Adamello intrusion stages and, more in general, with the widespread calc-alkaline magmatism described in the Southern Alps. Fission track ages of magmatic apatites are indistinguishable from U-Pb crystallization ages of zircons, suggesting that the intrusion occurred in country rocks already exhumed above the partial annealing zone of apatite (depth < 2-4 km). These data indicate that the northern and central sectors of the CSA were already structured and largely exhumed in the Middle Eocene and no major internal deformations has occurred in these areas after the Bartonian. Neogene deformations were instead concentrated further south, along the frontal part of the belt (Milano Belt). These new data provide a direct evidence that thrusting and nappe stacking were active during Late Cretaceous times not only in the Eastern Alps, but also in the CSA, significantly extending southward the sector of the Alpine belt affected by the Cretaceous orogenic event. In this view, the Late Cretaceous Southern Alps can be interpreted as the south-verging retrobelt of a pre-collisional orogenic wedge, which formed during the subduction of the Alpine Tethys beneath the attenuated northern Adria margin.

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Moreira, Pedro Augusto Franco Pinheiro. "Estudo sobre annealing de traços de fissão em apatitas de diferentes composições químicas e em faces sem orientação cristalográfica preferencial." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/278582.

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Orientadores: Pedro Jose Iunes, Julio Cesar Hadler Neto
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-08-10T04:22:14Z (GMT). No. of bitstreams: 1 Moreira_PedroAugustoFrancoPinheiro_D.pdf: 1517543 bytes, checksum: 91ec16c076345cdfaec5e3c787cd13e2 (MD5) Previous issue date: 2008
Resumo: Nesta tese estudou-se de forma geral sobre o annealing de traços de fissão em apatita, visando principalmente aplicações práticas da Termocronologia por Traços de Fissão. Para isso obteve se um conjunto de dados que possibilitasse que medidas de campo pudessem ser feitas em faces sem orientação cristalográfica preferencial, porque isso permite que seja considerado um número maior de traços fósseis nas "medidas de campo". Neste conjunto o amplo espectro de concentração de cloro encontrado nas apatitas naturais foi refletido, utilizando-se os extremos das concentrações de cloro (0,01 e 5 %), procurando-se incluir apatitas brasileiras. Outra característica marcante do presente conjunto foi à determinação das densidades de traços concomitantemente às medidas de comprimento. Para a escolha dos tratamentos térmicos para a confecção do conjunto, foi desenvolvida uma metodologia baseada em um algoritmo estatístico que foi aplicado a equações cinéticas com dados de annealing já estabelecidos antes dos dados apresentados neste trabalho. Cada amostra deste conjunto de dados de annealing foi submetida a dois ataques químicos diferentes: (1) durante 20 s em 5 M de HNO3 a 20° C e; (2) durante 45 s em 1,5 M de HNO3 a 20° C. Assim, comparou-se os efeitos destes dois ataques químicos em amostras que sofreram diferentes tratamentos térmicos. Os resultados indicaram que os comprimentos de traços encurtados pelo annealing não são influenciados por diferenças na concentração dos ataques padrões. Os tempos ótimos para a realização dos ataques foram estabelecidos através de três curvas de ataques químicos. A partir da interpretação dessas curvas desenvolveu-se um modelo cinético de ataque químico que descreve bem os dados apresentados nesta tese e baseia nos mesmos princípios do modelo cinético de annealing, que foi desenvolvido pelo Grupo de Cronologia da UNICAMP e contou com a colaboração deste autor. Este modelo de annealing foi ajustado aos dados de Carlson et al. (1999) permitindo compará-los com os dados aqui apresentado. No presente trabalho os resultados foram obtidos em faces sem orientação cristalográfica preferencial (onde foram medidos tanto traços-em-traços como traços em fraturas) e os resultados de Carlson et al. (1999) foram obtidos em faces prismáticas (onde foram medidos apenas traços-em-traços). Não houve sistematicidade na posiçao dos pontos obtidos neste trabalho com relação às curvas justadas aos dados de Carlson et al. (1999), porém, apontou uma dispersão relativamente grande deles em relação aos seus respectivos ajustes. Essa dispersão foi atribuída à anisotropia de ataque químico levando-se em conta que em faces cristalográficas sem orientação preferencial existem mais traços que podem ser confundidos com defeitos do que em faces prismáticas. Os resultados de uma forma geral indicam que medidas feitas em faces sem orientação cristalográfica preferencial (com traços-em-traços e traços em fraturas) podem ser consideradas em medidas de campo sem alterar de forma significativa as histórias térmicas, desde que os comprimentos reduzidos sejam maiores que 0,65
Abstract: In this thesis the fission track annealing in apatite was studied in a general way, considering mainly practical applications of Fission Track Termochronology. A data set that allows the use of randomly oriented grains was done, because a greater number of fossil tracks could be considered in the "field measures". Apatites with a broad chlorine spectrum (0.01 and 5%) in their compositions were used and it was included Brazilian apatites. Density measures were determinated together with length ones in this data set. The heat treatments used in this data set was chosen through a methodology was developed based on a statistical algorithm. This algorithm has been applied to kinetic equations fitted for another annealing data set established before the presented one in this work. The data set two was done with two different chemical etching for each sample: (1) for 20 s at 5 M of HNO3 at 20° C and, (2) for 45 s at 1.5 M of HNO3 at 20° C. Thus, it was possible to compare effects of these two etchings in samples which suffered different heat treatments. The results indicated that annealing length data sets are not influenced by differences in the standard chemical concentration of these etchings. The optimal etching times were established through three etching paths. From the interpretation of these paths, it was developed a chemical etching kinetic model that describes well the data presented here. This model is based on the same principles as the annealing kinetic model which was elaborated by the Group of Chronology that counted with the collaboration of the author of this thesis. This annealing model allowed the comparison between the data presented here and the data set by Carlson et al. (1999) through the fit of this model in the set of Carlson. The results of this thesis were obtained in randomly oriented grains where were measured track-in-track and track-in-cleavage and results of Carlson et al. (1999) were obtained in prismatic faces in which were measured only track-in-track. The comparison between the results showed that there is no tendency in position of the points obtained from this work. However, there is a dispersion of them in relation to their respective fits relatively large. This dispersion has been attributed to etching anisotropy taking into account that tracks in randomly oriented grains can be easier confused with defects than in prismatic faces. The results in general show that measures made in randomly oriented grains (with track- in-track and track-in-cleavage) may be considered field measures without changing the thermal histories in significant way, provided that the reduced lengths are greater than 0.65
Doutorado
Física Nuclear
Doutor em Ciências

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Lelarge, Maria Lidia Meideros Vignol. "Thermochronologie par la méthode des traces de fission d'une marge passive (dôme de Ponta Grossa, se Brésil) et au sein d'une chaîne de collision (zone externe de l'arc alpin, France)." Université Joseph Fourier (Grenoble), 1993. https://tel.archives-ouvertes.fr/tel-00603209.

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La méthode de datation par les traces de fission sur apatite a été appliquée dans deux contextes différents: une marge passive (dôme de Ponta Grossa dans l'état du Paraná au sud-est du Brésil) et une chaine de collision (massifs de Belledonne et du grand Châtelard, ainsi que la zone dauphinoise interne, dans les Alpes occidentales françaises). L'objectif de ce mémoire était de retracer l'histoire du refroidissement des roches de ces deux régions et dans une certaine mesure d'établir une chronologie des processus géodynamiques qui s'y sont produits. Les apatites du dôme de Ponta Grossa ont enregistré le refroidissement provoqué par la surrection-érosion de la serra do mar, chaïne montagneuse qui longe la côte sud-est brésilienne. La serra do mar correspond probablement a une réponse tardive à l'ouverture de l'Atlantique sud, qui s'est effectuée vers 120 MA aux environs de la latitude 26s. Les âges tracés de fission (tf) apparents des 21 échantillons analyses s'échelonnent entre 100 MA et 80 MA. L'analyse des résultats tf sur apatite, obtenus sur les 33 échantillons alpins, indique que l'histoire du refroidissement de cette région est extrêmement complexe. Les âges apparents tf sont compris entre 7,5 MA et 1,7 MA. Les taux de dénudation sont variables selon le secteur étudié et expriment ainsi un comportement différent vis-à-vis des processus tectoniques. Depuis le miocène supérieur jusqu'a 1 MA, les taux de dénudation apparents sont estimes a 0,4 mm/an pour le massif de Belledonne et à 0,7 mm/an pour le grand Châtelard et la zone du flysch. A partir d'un million d'années jusqu'à l'actuel le taux de dénudation apparent augmente et devient de l'ordre de 2 mm/an, pour l'ensemble de la région

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Rabone, Jeremy Andrew Leslie. "Molecular dynamics of fission track annealing in apatite minerals." Thesis, Birkbeck (University of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.499138.

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Grivet, Manuel. "Contribution a l'analyse du phenomene de recuit thermique des traces de fission de l'uranium dans l'apatite." Besançon, 1994. http://www.theses.fr/1994BESA2008.

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Les traces de fission spontanees de l'uranium dans l'apatite permettent la datation de ce mineral. Cependant, elles sont sensibles a une elevation de temperature en disparaissant progressivement. La technique couramment utilisee pour caracteriser l'etat de recuit des traces est la mesure de leurs longueurs par microscopie optique, apres revelation par un agent chimique approprie. C'est la repartition de ces longueurs qui est la plus a meme de nous fournir l'essentiel de l'histoire thermique de l'echantillon. C'est pourquoi nous proposons et developpons un modele de calcul permettant de simuler les histogrammes de longueurs projetees des traces de surface. A partir de ce modele, il est possible de transposer la repartition des longueurs en une construction graphique dans laquelle intervient l'echelle des temps: c'est la fonction d'age. Celle-ci permet d'obtenir des renseignements importants sur l'histoire thermique tels que la date de passage a 120#oc ou le temps de residence dans la zone de retention partielle des traces. Plusieurs applications de ce modele sur des materiaux geologiques sont presentees. Par ailleurs, une etude en microscopie electronique a transmission du diametre de double-repliques de traces d'ion kr, en fonction des temps de recuit et de revelation, est decrite. Elle montre une dependance de la vitesse d'attaque chimique radiale des traces vis-a-vis du temps de recuit et de la profondeur atteinte a l'interieur du mineral. Elle met aussi en evidence une evolution de la dispersion des diametres avec le recuit. Dans l'analyse mathematique des cinetiques d'effacement et de production des traces, ce dernier resultat nous conduit a utiliser un terme d'energie d'activation variant en fonction du recuit. Le but de cette approche est de resoudre de maniere unique le probleme de reconstruction d'histoires thermiques a partir de repartitions de longueurs de traces

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Meyer, Arnaud J. "Les traces de fission dans l'apatite : étude expérimentale et application à l'histoire thermique de bassins sédimentaires." Vandoeuvre-les-Nancy, INPL, 1990. http://www.theses.fr/1990INPL084N.

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Le nombre des traces de fission spontanée dans un minéral est fonction de son âge, de sa concentration en uranium et de son histoire thermique, les longueurs et les densités diminuant avec l'augmentation de la température. Une étude a été réalisée sur les temps nécessaires pour atteindre la révélation complète des densités et des longueurs des traces de fission induites en fonction des conditions d'attaque utilisées. L'influence des conditions d'observation et des critères de mesures choisis sur les distributions des longueurs projetées des traces et sur la reproductibilité et la précision des mesures, a également été examinée. Une expérience a été réalisée, prouvant que deux populations de traces de fission peuvent être reconnues et séparées à partir des longueurs projetées. La méthode de correction des âges-plateaux a été appliquée à l'apatite de Durango (Mexique) pour tester l'utilisation de cette apatite comme standard d'âge. Des expériences de recuit des traces réalisées en laboratoire ont permis de quantifier la relation entre les taux de réduction des longueurs (l/lo) et des densités (p/po) des traces de fission et de définir les conditions de stabilité des traces suivant nos conditions expérimentales. Un programme de modélisation de l'évolution de la longueur des traces sous l'effet d'une histoire thermique donnée a été employé pour illustrer la réponse des paramètres traces de fission en fonction de la profondeur, à trois histoires thermiques différentes (simple enfouissement, variation du gradient géothermique et érosion). De tous les exemples étudiés, la méthode des traces de fission apparait être un outil fiable pour la reconstitution de l'histoire thermique d'une roche, permettant de dater et de préciser les températures d'évènements dia génétiques et, comparée aux données d'autres géochrono- et géothermomètres de les intégrer dans un contexte géodynamique plus large

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Brown, Summer Jasmine. "Integrating apatite (U-Th)/He and fission track dating for a comprehensive thermochronological analysis: refining the uplift history of the Teton Range." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/32718.

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Uplift of the Teton Range is primarily controlled by displacement across the range-front Teton normal fault. The Tetons comprise the footwall block while the hanging wall encompasses Jackson Hole valley and a portion of the Snake River. Relative to the rest of the Rocky Mountains, the Tetons experienced the majority of uplift very recently, substantiating the need for a detailed investigation integrating structural analysis and bedrock thermochronometry. New low-temperature cooling ages are documented in three vertical transects across the Teton Range and at low elevations parallel to the Teton fault. Samples adjacent to the Teton fault are consistently young (~9 Ma) and represent a minimum estimate for the onset of Teton fault-related uplift. Modeling of time-temperature histories supports a ~9-11 Ma onset of rapid uplift, indicating that the Teton fault likely originated as a Basin and Range-type structure. A maximum throw of ~8 km occurs proximal to the Grand Teton, while the average throw for the entire ~100 km along-strike fault length is ~3.3 km. Thus, the geometry of the Teton fault is comparable to traditional scaling relationships dictating a correlation between fault length and displacement. Inversion of the typical (U-Th)/He (AHe) and fission track (AFT) relationship in a few of the Teton Range samples is a result of intense zoning, primarily in apatite from Precambrian layered gneisses. Nonetheless, both the AHe and AFT ages consistently indicate slight differential uplift of the Tetons between the Late Oligocene and Middle Miocene. HeFTy models indicate that doming of the Precambrian-Paleozoic unconformity occurred prior to ~50 Ma. However, by ~15 Ma, rapid cooling of the Mount Moran section essentially â flattenedâ the unconformity. Thus, the modern domed shape is a result of displacement across the Teton fault, allowing the unconformity to be used as a proxy for fault deformation. Moreover, reconstruction of the unconformity and volume calculations produced an average depth to incision of ~0.3 km and a long-term erosion rate of 0.18 mm/yr. Compared to the long-term uplift rate of 0.22 mm/yr, this provides a quantitative explanation for the modern Teton topography.
Master of Science

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Ribeiro, Marli Carina Siqueira [UNESP]. "Termocronologia e história denudacional da Serra do Mar e implicações no controle deposicional da Bacia de Santos." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/103022.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Neste trabalho são apresentados os resultados obtidos por meio de análises geomorfológicas (Mapa de Níveis de Paleosuperfícies) e termocronológicos (traços de fissão em apatitas e U-Th/He em apatitas) ao longo da Serra do Mar nos setores (1), (2), (3) e (4). As correlações entre as analises geomorfológicas e termocronológicas evidenciaram uma geológica e geomorfológica compreendida entre o Cretáceo Superior e Paleoceno, demonstrando que a evolução das morfologias que compõem a área de estudo estiveram associadas a eventos tectônicos e sucedidos por uma intensa atividade erosiva. De acordo com as datações realizadas utilizando termocronômetros com temperatura de fechamento distintas, estes indicaram que as configurações dos relevos que compõem a Serra do Mar não podem ser associadas apenas aos efeitos das atividades erosivas (recuo de escarpa) e isostáticas, para poderem explicar a homogeneidade entre as idades de traços de fissão e (U-Th)/He em apatitas, sem a presença da atuação tectônica soerguendo e desnivelando parte destes relevos.
In this paper the results obtained geomorphological analysis (Map of levels of Palaeosurfaces) and thermochronogical analysis (apatite fission-track and UTh/ He). The correlation between the geomorphologica and the thermochronological analysis evidenced a geological and geomorphological evolution from the Upper Cretaceous to the Palaeocene, showing that the evolution of the morpholoies composing the study area were associated to tectonics events and preceded by intense erosive activity. According to the datings done using thermocronometers with distinct closing temperatures the configuration of the relieves that compose the Serra do Mar can not be associated only to the effects of the erosive (escarpment retreate) and isostatic activities but also to the tectonic motion uplifting and unlevelling part such morphologies, in order to explain the homogeneity between the ages of the fission-track and U-Th/He of apatites.

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Powell, Jeremy. "Burial and Exhumation History of the Mackenzie Mountains and Plain, NWT, Through Integration of Low-Temperature Thermochronometers." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35994.

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The integration of low-temperature thermochronometers, including apatite and zircon (U-Th)/He (AHe, ZHe) and apatite fission-track (AFT) methods, allows for a quantification of the thermal history experienced by rocks as they heat and cool through upper crustal temperature regimes (<200°C). Whereas these methods are practical in geologic terranes that have undergone rapid cooling, application to strata with protracted cooling histories is complicated by the enhanced role of grain-specific parameters (volume, chemistry, radiation damage) on the kinetics of helium diffusion and fission track annealing. The effects of these variables are most prevalent in sedimentary samples, where natural variance in detrital accessory mineral populations results in a broad range of diffusion kinetics and great dispersion in corresponding cooling dates. This thesis integrates contemporary thermochronometer diffusion and annealing kinetics to investigate the burial and exhumation history of two natural laboratories. In the Mackenzie Mountains and Plain of the Northwest Territories, long-term radiation damage accumulation in zircon from Neoproterozoic siliciclastic units produces ZHe dates that track Albian to Paleocene burial and exhumation in front of the foreland-propagating fold-thrust belt. For the Phanerozoic stratigraphic section, AFT annealing kinetics are calculated from Devonian and Cretaceous samples, and are incorporated into multi-kinetic AFT modeling. These kinetics also constrain AHe date-radiation damage trends, and when combined allow for an estimation on the magnitude of eroded sediment across regional pre-Albian and post-Paleocene unconformities. Finally, conodont (U-Th)/He data from Anticosti Island, Québec in the Gulf of the St. Lawrence are compared with ZHe, AHe and AFT data to test their utility as a thermochronometer for carbonate basin analysis. These data evince a Mesozoic thermal history previously unattributed to the region. Ultimately, this thesis provides a novel assessment on the ways in which thermochronometer date dispersion can be quantified to assess the thermal evolution of sedimentary basins from burial through to inversion.

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Miller, Scott Ruthardt 1973. "Landscape development of the Transantarctic Mountains, Shackleton Glacier area, Antarctica: An integration of structural geology, geomorphology, and apatite fission-track thermochronology." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/278646.

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Models of the evolution of the modern Transantarctic Mountains, the uplifted flank of the West Antarctic rift system, require constraints on the timing, magnitude, and spatial pattern of surface uplift, rock uplift, denudation, and faulting. This study presents a model of Cenozoic landscape development for the Shackleton Glacier area (85°S, 176°W) by integrating structural geologic, geomorphologic, and apatite fission-track thermochronologic (AFTT) methods. Cenozoic denudation (up to 5-6 km) began ∼50 Ma near the Ross Ice Shelf coast and migrated inland by escarpment retreat, as evidenced in the AFTT and geomorphologic record. Dissected planation surfaces are scattered at elevations from 500 m to almost 4000 m above sea level and represent episodes of relative tectonic quiescence between periods of uplift. The fault structure of the range front is consistent with an interpretation of dextrally transtensional kinematics, which apparently accommodates a smaller transcurrent component than the greater West Antarctic rift system.

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Genaro, Daniele Tokunaga [UNESP]. "Contribuição ao conhecimento de processos atuantes no rifteamento continental, por traços de fissão em zircões e apatitas, aplicados no rift continental do sudeste do Brasil, bacias de Taubaté, Resende, Volta Redonda e circunvizinhanças." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/92905.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O Rift Continental do Sudeste do Brasil representa uma importante feição geológica, tanto por seu potencial econômico (areias, argilas, turfas e hidrocarbonetos), quanto para fins de estudos geológicos, pois trata-se de uma estrutura, de graben e horts, preservada e que não se encontra recoberto por águas, o que facilita suas pesquisas. Este estudo compreende a aplicação de análises termocronológicas por traços de fissão, em apatitas e zircões, com o intuito de verificar mudanças nos padrões térmicos que causaram alterações no ambiente, soerguimentos tectônicos, alçamento de isotermas e denudações. Utilizando para isto amostras coletadas em três bacias do segmento central (Taubaté, Resende e Volta Redonda). As idades obtidas remontam uma história complexa do ponto de vista evolutivo da região sudeste do Brasil, desde o Cretáceo Inferior, com o início do processo de quebramento do Continente Gondwana, passando por registros associados a intrusões alcalinas e um soerguimento regional, no início do Cretáceo Superior e finalmente entre o Paleoceno-Eoceno é resgatado o período em que ocorreu todo o processo de abertura do Rift Continental do Sudeste do Brasil (RCSB) e alterações em seu entorno. A disposição geral das idades por traços de fissão evidencia um envelhecimento em direção ao interior do continente, porém amostras muito próximas ao RCBS mostram um rejuvenescimento, possivelmente em função de um evento tectônico que culminou no surgimento das depressões que geraram as bacias deste rift. Cálculos de taxas de soerguimento e exumação mostram que os eventos foram intensificados durante o Cretáceo, aumentando consideravelmente os valores de soerguimento e exumação em períodos mais recentes. Com base nos resultados dos altos estruturais...
The Continental Rift of southeastern Brazil is an important geological feature, both for its economic potential (sand, clay, turfs and oil), as for geological studies, because it is a structure of graben and horsts, preserved and which is not covered by water, which facilitates their resources. This study includes the application of analysis of fission tracks in apatites and zircons, for determine changes in thermal patterns that a caused change in the environment, tectonic’s uplift, rises isotherms and denudations. Making use of samples collected in three basins of the central segment (Taubaté, Resende and Volta Redonda). The ages obtained a complex history dating back from the rolling region of southeastern Brazil, from the Lower Cretaceous, with the beginning of the Gondwana break, through records associated with alkaline intrusions and a strong uplift at the beginning of the Upper Cretaceous. Finally between Paleocene-Eocene is identified the time (interval) that happened all the process of opened the Brazilian Southern Continental Rift (RCSB) and changes around this structure. The general features of the age of fission shows an aging toward the interior of the continent, but samples near of RCBS shows a ages that have a rejuvenescence, possibly for apparition of basin of rift. Calculations of rates of exhumation and uplift show that the events have been intensified during the Cretaceous, increasing considerably the values in recent periods. Based on the results of high internal structural supports and between the basins, our agree ... (Complete abstract click electronic access below)

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Genaro, Daniele Tokunaga. "Contribuição ao conhecimento de processos atuantes no rifteamento continental, por traços de fissão em zircões e apatitas, aplicados no rift continental do sudeste do Brasil, bacias de Taubaté, Resende, Volta Redonda e circunvizinhanças /." Rio Claro : [s.n.], 2008. http://hdl.handle.net/11449/92905.

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Acompanha 2 mapas
Orientador: Peter Christian Hackspacher
Coorientador: Antonio Roberto Saad
Banca: Renato Rodriguez Cabral Ramos
Banca: Carlos Alberto Tello Saenz
Resumo: O Rift Continental do Sudeste do Brasil representa uma importante feição geológica, tanto por seu potencial econômico (areias, argilas, turfas e hidrocarbonetos), quanto para fins de estudos geológicos, pois trata-se de uma estrutura, de graben e horts, preservada e que não se encontra recoberto por águas, o que facilita suas pesquisas. Este estudo compreende a aplicação de análises termocronológicas por traços de fissão, em apatitas e zircões, com o intuito de verificar mudanças nos padrões térmicos que causaram alterações no ambiente, soerguimentos tectônicos, alçamento de isotermas e denudações. Utilizando para isto amostras coletadas em três bacias do segmento central (Taubaté, Resende e Volta Redonda). As idades obtidas remontam uma história complexa do ponto de vista evolutivo da região sudeste do Brasil, desde o Cretáceo Inferior, com o início do processo de quebramento do Continente Gondwana, passando por registros associados a intrusões alcalinas e um soerguimento regional, no início do Cretáceo Superior e finalmente entre o Paleoceno-Eoceno é resgatado o período em que ocorreu todo o processo de abertura do Rift Continental do Sudeste do Brasil (RCSB) e alterações em seu entorno. A disposição geral das idades por traços de fissão evidencia um envelhecimento em direção ao interior do continente, porém amostras muito próximas ao RCBS mostram um rejuvenescimento, possivelmente em função de um evento tectônico que culminou no surgimento das depressões que geraram as bacias deste rift. Cálculos de taxas de soerguimento e exumação mostram que os eventos foram intensificados durante o Cretáceo, aumentando consideravelmente os valores de soerguimento e exumação em períodos mais recentes. Com base nos resultados dos altos estruturais... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Continental Rift of southeastern Brazil is an important geological feature, both for its economic potential (sand, clay, turfs and oil), as for geological studies, because it is a structure of graben and horsts, preserved and which is not covered by water, which facilitates their resources. This study includes the application of analysis of fission tracks in apatites and zircons, for determine changes in thermal patterns that a caused change in the environment, tectonic's uplift, rises isotherms and denudations. Making use of samples collected in three basins of the central segment (Taubaté, Resende and Volta Redonda). The ages obtained a complex history dating back from the rolling region of southeastern Brazil, from the Lower Cretaceous, with the beginning of the Gondwana break, through records associated with alkaline intrusions and a strong uplift at the beginning of the Upper Cretaceous. Finally between Paleocene-Eocene is identified the time (interval) that happened all the process of opened the Brazilian Southern Continental Rift (RCSB) and changes around this structure. The general features of the age of fission shows an aging toward the interior of the continent, but samples near of RCBS shows a ages that have a rejuvenescence, possibly for apparition of basin of rift. Calculations of rates of exhumation and uplift show that the events have been intensified during the Cretaceous, increasing considerably the values in recent periods. Based on the results of high internal structural supports and between the basins, our agree ... (Complete abstract click electronic access below)
Mestre

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Mansour, El Mehdi. "Thermochronologie par la méthode des traces de fission dans l'apatite : application aux massifs de l'Argentera-Mercantour (Alpes occidentales) et des Jebilet (Meseta marocaine)." Grenoble 1, 1991. http://www.theses.fr/1991GRE10146.

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Dans les apatites des roches plutoniques et metamorphiques, les traces de fission (tf) de l'uranium 238 ne commencent a etre enregistrees que lorsque la temperature se situe au-dessous de 60-70c. Nous avons utilise cette propriete pour l'etude de l'histoire de refroidissement de deux massifs hercyniens: l'argentera-mercantour (alpes occidentales) et les jebilet (meseta marocaine). Apres avoir, dans la premiere partie de ce travail, expose l'etat actuel de la datation par tf et discute de ses applications et de ses limites pour les apatites, on expose les resultats d'un travail de calibration mene a partir d'irradiations dans trois reacteurs nucleaires: melusine (cen-grenoble), rhf (ill-grenoble) et orphee (cen-saclay). Dans l'argentera, 16 echantillons ont ete preleves selon une transversale nw-se. Les ages tf des apatites correspondantes montrent que le massif s'est refroidi au-dessous de 130c a partir de 10 ma et que sont taux apparent de surrection-erosion entre 10 ma est reste sensiblement constant, de l'ordre de 0,15-0,20 mm/an. Entre 2,8 ma et 0?3 ma, ce taux est passe a 0,60,1 mm/an pour le flanc sw et 0,90,2 mm/an du cote ne, en accord avec les mouvements differentiels deja mis en evidence par les donnees de la geologie. Dans les jebilet, les 7 echantillons etudies presentent des ages tf concordants. Le debut de l'enregistrement des traces, a 1866 ma, concorde avec l'age de l'ouverture de l'atlantique central. Il implique un paleogradient geothermique, au jurassique inferieur, de l'ordre de 55-60+c/km. Le dernier evenement thermique enregistre dans ces mineraux est, a 383 ma, la phase atlasique majeure

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Zhang, Xiaojing. "Tectonic Evolution of Taimyr in the Late Paleozoic to Mesozoic from Provenance and Thermochronological Evidence." Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-119046.

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The Taimyr Peninsula is a key element in the circum-Arctic region and represents thenorthern margin of the Siberian Craton. The Taimyr Peninsula is a late Paleozoic fold andthrust belt and preserves late Paleozoic through Mesozoic siliciclastic sedimentarysuccessions and providing an ideal location to investigate the Paleozoic to Mesozoictectonic evolution associated with the Uralian orogeny, the Siberian Trap magmatism andopening of Amerasia Basin within a circum-Arctic framework. Multiple methods areadopted, including petrography, heavy mineral analysis and detrital zircon U-Pbgeochronology for provenance investigation, apatite fission track dating for revealingthermal history and balanced cross section for understanding the deformation style ofTaimyr.The results of this thesis indicate that the Late Carboniferous to Permian sediments ofsouthern Taimyr were deposited in a pro-foreland basin of the Uralian orogen during theUralian orogeny. In the Triassic, the siliciclastic deposits still show a strong Uraliansignature but the initiation of Siberian Trap-related input begins to be significant. Erosionof the Uralian orogen has reached a deep metamorphic level. By Late Jurassic andCretaceous time, the deposition setting of southern Taimyr is an intracratonic basin.Erosion and input from Uralian sources waned while greater input from SiberianTrap-related rocks of the Taimyr region dominated. The Taimyr Peninsula underwent atleast three cooling and uplifting episodes: 280 Ma, 250 Ma and 220 Ma, corresponding tothe Uralian orogeny, the Siberian Traps and the late Triassic transpression.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: In press. Paper 3: Manuscript. Paper 4: Manuscript.

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Savignano, Elisa. "Apatite (U-Th)/He and Fission Track thermochronometry in the Northern Patagonian Andes: New insights into the exhumation history of the thrust belt foreland sector." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3421962.

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The study of the Cretaceous–Cenozoic evolution of the North Patagonian Andes represents a great opportunity to investigate the effects of coupling between deep lithospheric processes and near-surface deformation. Despite the general along-strike continuity, this mountain belt is characterized by a pronounced internal tectonic segmentation (marked by the variable position of the magmatic arc and of the deformation front to the east). Thus, this plate margin results in a more complex conﬁguration with respect to the simpliﬁed notion of “Andean-type” subduction system. Being located in the retro-wedge of the Andes, this sector of the Southern Cordillera experienced a complex evolution characterized by alternating flat- and steep-slab subduction stages, which controlled shortening and extension episodes in the overriding plate. Furthermore, the deformation in this whole retroarc sector varied not only in time (i.e. with major 'cycles' of mountain building and orogenic collapse), but also in space, due to the variable transmission of horizontal compressive stress away from the orogen, that produced an irregular unroofing pattern, recorded by obtained low-temperature (low-T) thermochronometric ages. Indeed, low-T thermochronological systems are ideally suited for detecting events involving rocks in the uppermost part of the crust because they record time and rates of cooling related to exhumation of the top few kilometers of the crust. In this study, apatite (U-Th)/He (AHe) and apatite fission track (AFT) dating are integrated with structural methods in the region located between 40° and 44°S. Two fieldwork periods were carried out throughout the Neuquén, Rio Negro, and Chubut Provinces in order to sample for thermochronological analyses and conduct structural surveys. These methods allowed us comparing the exhumation patterns both between the frontal part of the orogen and its adjacent foreland, and in the same morpho-structural domain at different latitudes. A total of 48 samples have been collected, processed and analyzed. AHe dating was performed at the University of Paris Sud, while AFT dating was done at the University of Padua. Detailed structural surveys were mainly conducted in the less studied zones of the foreland, and in the entire studied area to check major structures. Integrating the different methods allowed us to unravel the complex tectonic scenario characterizing the study area. Three balanced and sequentially restored cross-sections have been integrated with thermochronological information in order to produce a thermo-kinematic model along two different transects located at 40° and 42°S. To do this, the analyzed transects were processed with FetKin, a dedicated software for forward modeling of thermochronometric ages and age prediction along the present-day profile. This in turn, was used to validate the proposed tectonic scenario. New AFT and AHe data obtained in this study highlight two major tectonic events that occurred in North Patagonia: a Late Cretaceous to Paleogene inversion and exhumation stage, that involved the entire fold-and-thrust belt–foreland basin system, and a Miocene-Pliocene inversion stage of focused exhumation in the Andean fold-and-thrust belt. The suggested tectonic scenario was successfully tested with FetKin along the two transects, allowing us to unravel the role and extent of each tectonic stage that occurred since the Mesozoic. The recorded pattern may be interpreted as the result of a variable degree of propagation of the deformation from the Andean chain to the foreland. This appears to be controlled by two main parameters: (i) slab configuration (i.e. steep- vs. flat-subduction, which plays a fundamental role in foreland deformation), and (ii) convergence rate between the Pacific and South-America plates, which rules shortening and exhumation processes in the fold-and-thrust belt.
Lo studio dell’evoluzione Cretacico–Cenozoica delle Ande Nord Patagoniche offre l’opportunità di comprendere le relazioni intercorrenti tra processi profondi riguardanti la dinamica della litosfera e la deformazione più superficiale che coinvolge la crosta. Benché la catena andina sia caratterizzata da un generale andamento lineare nord-sud, nel dettaglio essa è fortemente segmentata da un punto di vista tettonico, come si evince dalla posizione variabile dell’arco magmatico e del fronte di deformazione verso le zone di avampaese. Pertanto, questo margine di placca risulta avere una complessa configurazione, che va oltre la comune nozione di sistema di subduzione di “tipo andino”. Localizzato nella zona di retrocatena, il settore Nord Patagonico della Cordigliera ha subito una complessa evoluzione, caratterizzata dall’alternanza di fasi di subduzione a basso e alto angolo, che ha controllato le fasi rispettivamente di raccorciamento e di estensione in corrispondenza della placca superiore. La variabilità deformativa in questa zona di retroarco è stata sia temporale—dunque legata a fasi di orogenesi e collasso della catena—sia spaziale, data la variabile trasmissione dello stress compressivo verso le zone esterne dell’orogene. La termocronologia di bassa temperatura è in grado di registrare i pattern irregolari di denudamento risultanti, essendo molto sensibile alle variazioni entro i primi chilometri della crosta. Tali sistemi termocronometrici sono ideali per identificare eventi tettonici a livello crostale, poiché sono in grado di registrare il momento e la velocità del raffreddamento legato all’esumazione. In particolare, i metodi (U-Th)/He (AHe) e tracce di fissione (AFT), entrambi su apatite, sono stati integrati in questa tesi con i metodi strutturali. L’area investigata è la regione ubicata tra 40° and 44°S, nel nord della Patagonia argentina. Durante le due campagne, condotte nelle Province di Neuquén, di Rio Negro e del Chubut, sono state campionate le rocce sulle quali compiere le analisi termocronologiche di bassa temperatura e sono stati analizzati dal punto di vista strutturale i lineamenti tettonici più importanti. Questi metodi hanno permesso sia di comparare i pattern di esumazione nella parte frontale della catena e nell’adiacente avampaese sia, al contempo, di comparare le differenze, a diverse latitudini, all’interno di uno stesso dominio morfo-strutturale. Complessivamente, sono stati raccolti, processati e analizzati quarantotto campioni. Le analisi (U-Th)/He sono state eseguite presso l’Università di Parigi Sud mentre quelle di tracce di fissione presso l’Università di Padova. Dal punto di vista geologico-strutturale, le maggiori strutture dell’area di studio sono state rilevate sul terreno e analizzate nel dettaglio, con particolare attenzione nelle zone meno studiate dell’avampaese. Infine, per un’analisi più approfondita di questo complesso scenario i due metodi sono stati integrati. Infatti, sono state costruite tre sezioni bilanciate e retrodeformate integrate con le informazioni termocronologiche al fine di produrre un modello termo-cinematico lungo due diversi transetti posti a 40° e 44°S, mediante l’utilizzo di un software dedicato in grado di modellare le età termocronometriche e fare previsione di queste lungo il profilo topografico odierno, che, a sua volta, è stato usato per validare lo scenario tettonico proposto. I nuovi dati AFT e AHe ottenuti nell’area di studio evidenziano due eventi tettonici principali interessanti l’area settentrionale della Patagonia: una fase d’inversione ed esumazione tra il tardo Cretacico e il Paleogene, che ha coinvolto l’intero sistema dalla catena all’avampaese, e una successiva, Mio-Pliocenica, in cui l’esumazione si è concentrata nella zona di catena. Questo scenario tettonico proposto è stato con successo testato lungo i due transetti analizzati attraverso FetKin, permettendo di chiarire il ruolo e l’entità di ogni fase tettonica avvenuta dal Mesozoico. Il pattern di esumazione così ottenuto è stato interpretato come il risultato del variabile grado di propagazione della deformazione dalla catena andina verso l’avampaese. Quest’ultimo sembra essere controllato principalmente da due parametri: (i) la configurazione della placca in subduzione, in altre parole la sua geometria più o meno orizzontale che gioca un ruolo fondamentale nella deformazione dell’avampaese, e (ii) la velocità di convergenza tra le placche pacifica e sud americana, che governa i processi di raccorciamento ed esumazione nella catena a pieghe e sovrascorrimenti.

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Sabil, Naïma. "La datation par les traces de fission : aspects méthodologiques et applications thermochronologiques en contexte alpin et marge continentale." Phd thesis, Université Joseph Fourier (Grenoble), 1995. http://tel.archives-ouvertes.fr/tel-00534619.

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La méthode de datation par les traces de fission de l'uranium s'est révélée unique dans le domaine de la thermochronologie par sa capacité à retracer l'histoire finale du refroidissement et dela dénudation de massifs métamorphiques comme de l'histoire thermique de formations sédimentaires ou la datation de certains matériels volcaniques. Dans ce travail, nous décrivons cette méthode et présentons un ensemble de techniques analytiques mises au point et de calibrations réalisées dans le but d'utilisations ultérieures en géologie. Nous discutons quelques exemples d'application. Dans les Alpes occidentales françaises, l'analyse des traces de fission sur apatites d'échantillons issus du granite des Sept Laux (massif de Belledonne), dans la vallée de l'Eau d'Olle, suggère que cette méthode pourrait apporter une contribution dans la discussion actuelle sur l'origine de certaines vallées alpines. Ainsi, l'ouverture de cette vallée pourrait être la conséquence d'un jeu de failles actives depuis le Miocène moyen jusqu'à l'actuel. La caractérisation par traces de fission des apatites détritiques de dépôts fluviaux pourrait éventuellement être utilisée pour l'étude d'éventuels phénomènes de captures liées à des changements de régimes tectoniques. Nous avons ainsi étudié les apatites d'un paléodelta situé dans la moyenne vallée de l'Isère au niveau du sillon subalpin et de deux vallées, celles de l'Arc et du Bréda, situées en amont. La distribution des âges traces de fission de ces minéraux n'a pas confirmé un modèle suggéré récemment, qui proposait que le paléodelta étudié pourrait être associé à un "paléo-Arc" plutôt qu'à un "paléo-Bréda". Dans la Meseta occidentale marocaine, trois massifs granitiques (massif de Sebt Brikiine, de Ras El Abiod et de Hjir El Bark) situés dans les Rehamna ont fait l'objet d'une étude thermochronologique. L' analyse des traces de fission dans les zircons et les apatites de ces granites montre qu'ils ont enregistré les grands évènements thermotectoniques ayant affecté la Meseta depuis l'ouverture de l'Océan Atlantique central. Nous montrons comment un modèle de simulation numérique récemment proposé (1994) pour l'analyse des traces de fission dans les apatites permet de préciser l 'histoire thermique des massifs considérés depuis le dernier refroidissement au-dessous d'environ l20°C des échantillons analysés. Dans des travaux effectués antérieurement à l'apparition de ce modèle, nous avons montré, d'une part, que les sédiments de la marge transformante de Côte d'Ivoire-Ghana avaient connu une période de réchauffement entre 250°C et moins de 60°C post-datant largement, de manière inattendue, son "balayage" par une dorsale océanique. D'autre part, dans l'Ile d'Elbe, nous avons apporté les premières données "traces de fission" sur l'histoire de refroidissement de la granodiorite de Monte Capanne. Par ailleurs, au début des années 90, la méthode des traces de fission manquait encore de bons échantillons de référence pour la datation des verres volcaniques. A La suggestion de la Sous Commission de Géochronologie de l'International Union ofGeological Sciences, nous avons étudié les macusanites, obsidiennes du SE péruvien. Les résultats de ce travail suggèrent qu'il faut considérer avec réserve ces verres volcaniques en tant que standards d'âge potentiels, même s'ils conservent une certaine valeur comme matériel d'intercalibration entre laboratoires.

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Robbins, Rebecca. "Petrology, structure and exhumation of the southern Sawatch mountains, south-central Colorado." Thesis, Manhattan, Kan. : Kansas State University, 2005. http://hdl.handle.net/2097/88.

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Tinker, Justine. "Quantifying South African uplift : using apatite fission track thermochronology and offshore sediment volumes to test the balance between denudation (onshore) and deposition (offshore) since Gondwana break-up." Doctoral thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/4228.

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Gomes, Cristiane Heredia. "História térmica das regiões sul e sudeste da América Do Sul : implicações na compartimentação geotectônica do Gondwana." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/56288.

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Estudos termocronológicos por traços de fissão em apatita são utilizados para estabelecer os principais eventos de denudação, erosão e subsidência na margem continental emersa do sul do Brasil e Uruguai. Os dados obtidos permitem verificar que as idades aparentes de traços de fissão variam de 383,4 ± 40,9 a 9,7 ± 1,2 Ma, entre o Devoniano Superior e o Mioceno, com comprimento dos traços de fissão entre 14,02 a 8,87 μm. A correlação entre idade e distribuição do comprimento dos traços de fissão confinados evidencia que as amostras sofreram diferentes reduções no comprimento dos traços de fissão. Isto indica que as rochas foram submetidas a diferentes posições crustais, paleotemperaturas e tempo de residência na Zona de Apagamento Parcial. As histórias térmicas obtidas mostram que processos de resfriamento lentos e contínuos foram registrados nas regiões desde o final do Pensilvaniano (Neopaleozóico). Os padrões de denudação são complexos, mas foi possível caracterizar no Uruguai e Rio Grande do Sul reflexos do evento orgênico Gondwanides (ou São Rafaélico) atuantes nas margens do Gondwana SW. Nas regiões do norte do Rio Grande do Sul, Santa Catarina e Paraná foi possível documentar com detalhe o recuo da escarpa da margem continental associada a fragmentação e dispersão mesocenozóica do Gondwana, com a definição de eventos de denudação em torno de: (i) 150-140 Ma, atribuído aos eventos pré-rifte a rifte; (ii) 90-80 Ma, associado ao magmatismo alcalino do Cretáceo Superior; (iii) eventos de 70-60 Ma e 45-35 Ma associados a rearranjos isostático da placa Sul-Americana na região estudada. Evento mais jovem com idades entre 20-10 Ma é reconhecido na margem continental do leste do RS e Uruguai, diretamente conectado à formação do Cone do Rio Grande.
Apatite fission track (FT) thermochronological analyses are used to establish the main events of denudation, erosion and subsidence of the emerse continental margin of South Brazil and Uruguay. The obtained data provide apparent ages ranging from 383.4 ± 40.9 Ma to 9.7 ± 1.2 Ma, between Upper Devonian and Miocene, and mean track length from 14.02 μm to 8.87 μm. Thermal history reconstruction based on apatite fission track thermochronology suggest the occurrence of long term and continuous cooling as well rapid uplift in investigated regions, recorded from Neopaleozoic to the Miocene. The oldest denudation event is well recorded in the Uruguay and Rio Grande do Sul as result of orogenic processes at margin of SW Gondwana, the so-called Gondwanides or San Rafael cycle. In the northern portion of Rio Grande do Sul, Santa Catarina and Paraná was possible to document the escarpment retreat across the rifted continental margin connected to the Mesocenozoic fragmentation and dispersion of Gondwana, defined by the main denudation event as follow: (i) 150-140 Ma, developed during the pre-rift and rift stages; (ii) 90-80 Ma, associated to Upper Cretaceous alkaline ; (iii) 70-60 Ma and 45-35 Ma events due to isostatic rearrangement of South American plate in the study area. The youngest denudation event, aged at 20-10 Ma, is very well defined in the emerse continental margin of east Rio Grande do Sul and Uruguay, and coeval to the Rio Grande Cone formation, a large sedimentary package of 4000 m thick.

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Barbarand, Jocelyn. "Cinétique de cicatrisation des traces de fission dans les cristaux d'apatite et histoire thermique de la bordure sud-est du Massif Central." Nancy 1, 1999. http://docnum.univ-lorraine.fr/public/SCD_T_1999_0052_BARBARAND.pdf.

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Les facteurs contrôlant la cinétique d'effacement des traces de fission dans les cristaux d'apatite ont été étudiés à partir de cristaux d'apatite issus d'environnements géologiques variés ayant connu un recuit des traces de fission naturel ou expérimental. La chimie des cristaux a été déterminée par cathodoluminescence, microsondes électroniques et ioniques. La cathodoluminescence apparait comme une méthode particulièrement adaptée pour étudier les zonations des cristaux d'apatite et pour tester l'homogénéité d'une population de grains. Ainsi, les échantillons possédant plusieurs populations de cristaux sont mis en évidence. De plus, la spectrométrie de cl fournit des données semi-quantitatives sur les teneurs des terres rares gd 3 +, ce 3 +, tb 3 +, dy 3 + et sm 3 +. La relation entre la cinétique de cicatrisation et la chimie des cristaux n'est pas univoque. Les expériences de recuit montrent que plusieurs facteurs jouent sur la stabilité des traces ; en particulier, le rapport c1/f, la teneur en terres rares légères et le degré de substitution des cristaux. Cependant, pour les exemples de recuit naturel, les contrôles varient selon les échantillons et peuvent apparaitre contradictoires. Des expériences couplées permettent d'établir une relation entre la cicatrisation des traces de fission et la maturation de la matière organique exprimée par les valeurs du tmax. L'analyse des traces de fission dans les cristaux d'apatite a été appliquée à la bordure sud-est du massif central. Les âges sont compris entre 25 et 209 ma et des longueurs des traces confinées entre 10,5 et 13,7 m avec des histogrammes de distribution dissymétriques vers les traces courtes. L'histoire thermique basse température de la bordure se résume : 1) à un basculement du sud vers le nord qui s'est initié à la fin du jurassique et qui a entrainé le soulèvement de la région ; 2) à une période calme au crétacé supérieur et enfin 3) à une importante phase d'érosion à partir du début du tertiaire qui a affecté la bordure par un retrait d'escarpement.

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Bermudez, Cella Mauricio Alberto. "Exhumation Cénozoïque dans les Andes Vénézuéliennes: apport de la thermochronologie par traces de fission." Phd thesis, Université Joseph Fourier (Grenoble), 2009. http://tel.archives-ouvertes.fr/tel-00450838.

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Cette thèse présente les résultats d'une étude de l'histoire à long terme (Miocène – actuel) de l'exhumation des Andes vénézuéliennes, ses rapports avec des structures héritées et le développement de la topographie en réponse à la tectonique et les processus de surface. Les Andes vénézuéliennes constituent un exemple idéal pour étudier les rapports entre ces processus. Elles montrent des inversions et réactivations de structures pré-existantes et sont associées à un gradient climatique majeur dû à l'effet orographique de la chaîne. Par ailleurs, de nombreuses données sont disponibles concernant leur récente évolution tectonique. Cette chaîne de montagne résulte de la transpression causée par la convergence oblique du bloc continental de Maracaibo et de la plaque Amérique du Sud contrôlée, à plus grande échelle, par la jonction triple entre les plaques Amérique du Sud, Caraïbe et Nazca. La cinématique complexe de cette interaction triple et l'évolution continue des structures qui y sont liées, couplée avec les processus de surface, ont profondément affecté l'évolution des Andes vénézuéliennes. Une base de données thermochronologiques de basse température est présentée dans cette thèse, composée de 47 nouveaux âges par traces de fission sur apatite (AFT): 24 échantillons in-situ provenant du substratum rocheux, 15 échantillons de sédiments synorogéniques et 8 échantillons de sédiments de rivières actuelles. La base de données a été augmentée de 27 âges AFT du substratum rocheux et 10 âges AFT existants ont été révisés, ces derniers 37 âges ayant été fournis par B.P Kohn (Université de Melbourne, Australie). Les âges AFT ont été convertis en taux d'exhumation à long terme en utilisant des modélisations numériques de l'évolution thermique. Les analyses des données AFT in-situ ont permis de délimiter sept blocs tectoniques avec des histoires d'exhumation variables à travers les Andes Vénézuéliennes. Les blocs de Caparo et de Valera sur les deux extrémités de la chaîne, qui ont été séparés par le mouvement dextre de la faille du Boconó, montrent des âges entre 7 et 27 Ma et entre 11 et 145 Ma respectivement. Ces blocs représentent des zones d'exhumation relativement lente. Dans la partie centrale des Andes Vénézuéliennes, les âges AFT des blocs de la Sierra La Culata (5-8 Ma), d'El Carmen (2-3 Ma) et de la Sierra Nevada (5-8 Ma) enregistrent une exhumation majeure récente qui répond à la transpression et l'érosion au long du système de failles du Boconó. Sur les deux flancs de la chaîne, les âges AFT dans le bloc d'El Escalante (5-6 Ma) au nord, et le bloc chevauché du Cerro Azul (5-8 Ma âge AFT) au sud indiquent une phase de compression importante, à l'origine de la structure à double vergence des Andes vénézuéliennes, pendant le Miocène Supérieur. Les analyses AFT sur apatite détritique dérivé de l'échantillonnage des rivières actuelles ont permis a) d'extrapoler les âges in-situ à travers les Andes vénézuéliennes, b) de déterminer la provenance des sédiments, et c) d'analyser les rapports entre taux d'exhumation et les facteurs de contrôle potentiels. Les résultats indiquent une forte corrélation entre le relief et le taux d'exhumation à long terme mais une absence de corrélation entre les taux d'exhumation à long terme et les précipitations actuelles ou la libération d'énergie sismique (mesurées au cours des 20 dernières années), indiquant que le contrôle de la tectonique et / ou des processus climatiques sur l'exhumation ne peut être distingué d'une manière simple. L'analyse AFT sur des sédiments syn-orogéniques des bassins d'avant-pays de Maracaibo et de Barinas ont permis d'établir un schéma de l'exhumation depuis le Miocène tardif jusqu'à l'actuel. Des analyses Rock-Eval sur sédiments Mio-Pliocènes montrent que ces séries n'ont pas été enfouies plus profondément que la zone de recuit partiel des AFT (PAZ), au moins sur les sections étudiées. Des âges AFT jeunes dans des échantillons provenant de la Formation Parángula sur le flanc sud indiquent que cette formation a probablement un âge Miocène moyen, nettement plus jeune que précédemment admis. Les données AFT combinées avec des analyses palynologiques révèlent que la Formation Pliocène de Betijoque sur le flanc nord correspond à la partie supérieure de la Formation Río Yuca au sud des Andes vénézuéliennes.

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Persano, Cristina. "A combination of apatite fission track and (U-Th)/He thermochronometers to constrain the escarpment evolution in south eastern Australia : a case study of high elevation passive margins." Thesis, University of Glasgow, 2003. http://theses.gla.ac.uk/1133/.

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In this project apatite fission track and (U-T)/He thermochronometers are used to determine the cooling history of rocks from the coastal (south eastern New South Wales) and the interior (Bathurst area) regions of the eastern Australia high elevation passive margin. Two traverses across the coastal lowlands, escarpment and plateau top are used to determine the tempo and styles of response of the landscape to the continental breakup and sea-floor spreading of the Tasman Sea (85 Ma). The three prevailing models of escarpment evolution namely retreat into a downwarped rift shoulder, escarpment retreat and excavation in place on a high elevation rift shoulder with flexural rebound are described and tested using a previously untested combination of apatite fission track and (U/Th)/He data. The thermochronological data indicate that the coast was affected by a denudational pulse that peaked around 120-100 Ma and that was extinguished by the time of sea-floor spreading. The rapid denudational event caused the removal of 3-4.5 km (depending on the geothermal gradient) of crust at the coast and of approximately 2 km at the present base of the escarpment. The thermochronological data are inconsistent with the downwarped rift shoulder model and the apatite (U-Th)/He data indicate that, while the coast was denuded very rapidly, the coastal lowlands were excavated in place at a much lower pace, and the escarpment reached its present position no later than 60 Ma. This suggests that during continental extension and breakup, rates of denudation at the coast were approximately 80-30m/Myr (depending on the geothermal gradient), whereas at the base of the present escarpment they were about 10-5 m/Myr. The period after sea-floor spreading was characterised by stability and low rates of erosion. The pre-breakup topography, reconstructed using the backstacking technique, is characterised by a considerable relief in the area of the present escarpment. This result confirms the hypothesis that the escarpment evolved pinned to its present position.

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Painter, Clayton S. "Sequence Stratigraphy, Geodynamics, and Detrital Geo-Thermochronology of Cretaceous Foreland Basin Deposits, Western Interior U.S.A." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/307071.

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Three studies on Cordilleran foreland basin deposits in the western U.S.A. constitute this dissertation. These studies differ in scale, time and discipline. The first two studies include basin analysis, flexural modeling and detailed stratigraphic analysis of Upper Cretaceous depocenters and strata in the western U.S.A. The third study consists of detrital zircon U-Pb analysis (DZ U-Pb) and thermochronology, both zircon (U-Th)/He and apatite fission track (AFT), of Upper Jurassic to Upper Cretaceous foreland-basin conglomerates and sandstones. Five electronic supplementary files are a part of this dissertation and are available online; these include 3 raw data files (Appendix_A_raw_isopach_data.txt, Appendix_C_DZ_Data.xls, Appendix_C_UPb_apatite.xls), 1 oversized stratigraphic cross section (Appendix_B_figure_5.pdf), and 1 figure containing apatite U-Pb concordia plots (Appendix_C_Concordia.pdf). Appendix A. Subsidence in the retroarc foreland of the North American Cordillera in the western U.S.A. has been the focus of a great deal of research, and its transition from a flexural foreland basin, during the Late Jurassic and Early Cretaceous, to a dynamically subsided basin during the Late Cretaceous has been well documented. However, the exact timing of the flexural to dynamic transition is not well constrained, and the mechanism has been consistently debated. In order to address the timing, I produced new isopach maps from ~130 well log data points that cover much of Utah, Colorado, Wyoming and northern New Mexico, producing in the process, the most detailed isopach maps of the area. These isopach maps span the Turonian to mid-Campanian during the Late Cretaceous (~93–76 Ma). In conjunction with the isopach maps I flexurally modeled the Cordilleran foreland basin to identify when flexure can no longer account for the basin geometry and identified the flexural to dynamic transition to have occurred at 81 Ma. In addition, the dynamic subsidence at 81 Ma is compared to the position of the hypothesized Shatsky Oceanic Plateau and other proposed drivers of dynamic subsidence. I concluded that dynamic subsidence is likely caused by convection over the plunging nose of the Shatsky Oceanic Plateau. Appendix B. The second study is a detailed stratigraphic study of the Upper Cretaceous, (Campanian, ~76 Ma) Sego Sandstone Member of the Mesaverde Group in northwestern Colorado, an area where little research has been done on this formation. Its equivalent in the Book Cliffs area in eastern Utah has been rigorously documented and its distal progradation has been contrastingly interpreted as a result of active tectonism and shortening in the Cordilleran orogenic belt ~250 km to the west and to tectonic quiescence, flexural rebound in the thrust belt and reworking of proximal coarse grained deposits. I documented ~17 km of along depositional dip outcrops of the Sego Sandstone Member north of Rangely, Colorado. This documentation includes measured sections, paleocurrent analysis, a stratigraphic cross section, block diagrams outlining the evolution of environments of deposition through time, and paleogeographic maps correlating northwest Colorado with the Book Cliffs, Utah. The sequence stratigraphy of the Sego Sandstone Member in northwest Colorado is similar to that documented in the Book Cliffs area to the south-southwest, sharing three sequence boundaries. However, flood-tidal delta assemblages between fluvio-deltaic deposits that are present north of Rangely, Colorado are absent from the Book Cliffs area. These flood-tidal-delta assemblages are likely caused by a large scale avulsion event in the Rangely area that did not occur or was not preserved in the Book Cliffs area. In regards to tectonic models that explain distal progradation of the 76 Ma Sego Sandstone Member to be caused by tectonic quiescence and flexural rebound in the thrust belt, the first study shows that at 76 Ma, flexural processes were no longer dominant in the Cordilleran foreland, so it is inappropriate to apply models driven by flexure to the Sego Sandstone Member. Dynamic processes dominated the western U.S.A. during the Campanian, and flexural processes were subordinate. Appendix C. In order to test the tectonic vs. anti-tectonic basin-filling models for distal coarse foreland deposits mentioned above, the third study involves estimating lag times of Upper Jurassic to Upper Cretaceous conglomerates and sandstones in the Cordilleran foreland basin. Measuring lag time requires a good understanding of both the stratigraphic age of a deposit and the thermal history of sedimentary basin. To further constrain depositional age, I present twenty-two new detrital zircon U-Pb (DZ U-Pb) sample analyses, spanning Upper Jurassic to Upper Cretaceous stratigraphy in Utah, Colorado, Wyoming and South Dakota. Source exhumation ages can be measured using thermochronology. To identify a thermochronometer that measures source exhumation in the North America Cordillera, both zircon (U-Th)/He, on eleven samples, and apatite fission track (AFT) thermochronology, on eleven samples was performed. Typically, the youngest cooling age population in detrital thermochronologic analyses is considered to be a source exhumation signal; however, whether or not these apatites are exhumed apatites or derived from young magmatic and volcanic sources has been debated. To test this, I double dated the detrital AFT samples, targeting apatites with a young cooling age, using U-Pb thermochronology. Key findings are that the maximum depositional ages using DZ U-Pb match existing biostratigraphic and geochronologic age controls on basin stratigraphy. AFT is an effective thermochronometer for Lower to Upper Cretaceous foreland stratigraphy and indicates that source material was exhumed from >4–5 km depth in the Cordilleran orogenic belt between 118 and 66 Ma, and zircon (U-Th)/He suggests that it was exhumed from <8–9 km depth. Double dating apatites (with AFT and U-Pb) indicate that volcanic contamination is a significant issue; without having UPb dating of the same apatite grains, one cannot exclude the possibility that the youngest detrital AFT population is contaminated with significant amounts of volcanogenic apatite and does not represent source exhumation. AFT lag-times are 0 to 5 Myr with relatively steady-state to slightly increasing exhumation rates. We compare our data to orogenic wedge dynamics and subsidence histories; all data shows active shortening and rapid exhumation throughout the Cretaceous. Our lag-time measurements indicate exhumation rates of ~.9–>>1 km/Myr.

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Ribeiro, Marli Carina Siqueira. "Termocronologia e história denudacional da Serra do Mar e implicações no controle deposicional da Bacia de Santos /." Rio Claro : [s.n.], 2007. http://hdl.handle.net/11449/103022.

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Orientador: Peter Christian Hackspacher
Banca: Norberto Morales
Banca: Sandro Guedes
Banca: Cláudio Riccomini
Banca: Pedro José Nunes
Resumo: Neste trabalho são apresentados os resultados obtidos por meio de análises geomorfológicas (Mapa de Níveis de Paleosuperfícies) e termocronológicos (traços de fissão em apatitas e U-Th/He em apatitas) ao longo da Serra do Mar nos setores (1), (2), (3) e (4). As correlações entre as analises geomorfológicas e termocronológicas evidenciaram uma geológica e geomorfológica compreendida entre o Cretáceo Superior e Paleoceno, demonstrando que a evolução das morfologias que compõem a área de estudo estiveram associadas a eventos tectônicos e sucedidos por uma intensa atividade erosiva. De acordo com as datações realizadas utilizando termocronômetros com temperatura de fechamento distintas, estes indicaram que as configurações dos relevos que compõem a Serra do Mar não podem ser associadas apenas aos efeitos das atividades erosivas (recuo de escarpa) e isostáticas, para poderem explicar a homogeneidade entre as idades de traços de fissão e (U-Th)/He em apatitas, sem a presença da atuação tectônica soerguendo e desnivelando parte destes relevos.
Abstract: In this paper the results obtained geomorphological analysis (Map of levels of Palaeosurfaces) and thermochronogical analysis (apatite fission-track and UTh/ He). The correlation between the geomorphologica and the thermochronological analysis evidenced a geological and geomorphological evolution from the Upper Cretaceous to the Palaeocene, showing that the evolution of the morpholoies composing the study area were associated to tectonics events and preceded by intense erosive activity. According to the datings done using thermocronometers with distinct closing temperatures the configuration of the relieves that compose the Serra do Mar can not be associated only to the effects of the erosive (escarpment retreate) and isostatic activities but also to the tectonic motion uplifting and unlevelling part such morphologies, in order to explain the homogeneity between the ages of the fission-track and U-Th/He of apatites.
Doutor

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Silva, Luiz Guilherme de Almeida do Eirado. "A interação entre os eventos tectônicos e a evolução geomorfológica da Serra da Bocaina, Sudeste do Brasil." Universidade do Estado do Rio de Janeiro, 2006. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=171.

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O relevo da Serra da Bocaina revela o forte controle das estruturas dúcteis e rúpteis relacionadas à Faixa Ribeira gerada na Orogênese Brasiliana (ca. 790-480 Ma) e às reativações mesozóica-cenozóicas. As rochas são agrupadas em 4 terrenos tectônicos colados nas etapas colisionais brasilianas, que formaram as estruturas mais penetrativas: foliação com mergulho para NW, zonas de cisalhamento dúcteis NESW e dobras. Zonas de cisalhamento rúptil-dúcteis NW marcam o colapso orogênico. A abertura do Atlântico Sul (ca. 135-120 Ma) é registrada pelos enxames de diques toleíticos NNE e ENE, em parte condicionados pelas estruturas brasilianas. No Planalto da Bocaina uma idade de traço de fissão em apatita (TFA) de ca. 145 Ma data o resfriamento ainda da fase pré-rifte do Gondwana. O soerguimento da margem continental na fase rifte pode ter alçado este nível para fora da zona de apagamento parcial do TFA. A reativação neocretácea é datada pelo TFA (ca. 85 Ma) na costa e na escarpa atlântica, indicando novo pulso de denudação e soerguimento da margem continental. Isto também concorda com o extenso aporte de sedimentação siliciclástica na Bacia de Santos. No Paleógeno, a formação dos Riftes Continentais do Sudeste Brasileiro (RCSB) gerou a reativação das estruturas dúcteis NE da Faixa Ribeira, falhas e fraturas NW, E-W, além de fraturas NE na Baía da Ilha Grande. O contato tectônico entre os Terrenos Paraíba do Sul e Embu é a principal zona reativada na Serra da Bocaina. Idades TFA (ca. 55 Ma) registram o estágio inicial do RCSB, que provocou o rebaixamento do nível de base e a formação de uma escarpa no interior. A Serra da Bocaina parece constituir uma região elevada desde a formação da Cordilheira Ribeira, incrementada pelos soerguimentos das fases rifte e pós-rifte do Atlântico e do RCSB. Estes eventos tectônicos que elevaram a Serra da Bocaina, também geraram as estruturas que conduzem sua denudação. Neste contexto, destaca-se o par de estruturas NE (foliação e zonas de cisalhamento reativadas ou não) e NW (fraturas e falhas), as mais freqüentes, que orienta a rede de drenagem, os níveis de base locais (knickpoints) e as formas côncavas das encostas (cabeceiras de canais). Diques toleíticos também conduzem a dissecação dos vales fluviais. Por outro lado, granitos e ortognaisses que sustentam as elevações e segmentos de escarpas mostram o papel da erosão diferencial em rochas mais resistentes. A denudação do Planalto da Bocaina e o recuo de suas escarpas (atlântica e interior) são regulados por diferentes níveis de base (p.ex. nível do mar, rio Paraíba do Sul no RCSB, diversos knickpoints), sensíveis aos eventos de reativações tectônicas (soerguimento), variações eustáticas e à erosão diferencial. Os pulsos erosivos vêm dissecando de modo diferencial os vales suspensos do planalto, através da incisão fluvial e reativação das cabeceiras de canais, que avançam sobre as encostas promovendo a quebra dos divisores e capturas de drenagens. Este processo rebaixamento de relevo parece levar à formação das superfícies colinosas que ocorrem em diferentes níveis topográficos. As idades TFA antigas indicam baixas taxas de denudação na porção mais elevada do Planalto da Bocaina, o que contrasta com as altas taxas da região costeira. Este caráter diferencial da denudação condicionada pelo substrato geológico e pelos eventos de soerguimento, vem preservando antigas paisagens no Planalto da Bocaina. No outro extremo, a denudação propagada pelo recuo das duas escarpas vem degradando as bordas e introduzindo a dissecação no interior do planalto. As duas escarpas geradas por eventos riftes distintos vêm se ajustando ao controle das rochas e estruturas da Faixa Ribeira.
The Bocaina Ridge landscape is strongly controlled by both ductile and brittle structures related to the Ribeira Belt (Brasiliano Orogeny ca. 790-480Ma) and also to the mesozoic-cenozoic reactivations. The rocks were subdivided in four tectonic terrains accreted in the brasiliano collisional stages. The most prominent structures related to these collisions are: NW dipping foliation, NE-SW ductile shear zones, and folds. NW ductile-brittle shear zones represent the orogenic collapse stage. The South Atlantic opening (ca.135-120 Ma) is registered in NNE and ENE tholeitic dike swarms, partly conditioned by brasiliano structures. In the Bocaina Plateau one apatite fission track age (AFT) of ca.145Ma represents pre-rift Gondwana cooling. The continental margin uplift associated to the rift phase might have raised this level out of the AFT partial annealing zone. Neocretaceous reactivation (ca. 85Ma) was AFT dated both in the coast and the atlantic scarp, pointing out to a newer continental margin denudation and uplift pulse. This reactivation is in accordance with the Santos basin significant siliciclastic sedimentation. In paleogene times, the Southeastern Brazil Continental Rift System (SBCR) development was responsible for: the reactivation of the Ribeira Belt NE ductile structures, NW and E-W faulting and fracturing, and NE fracturing in Ilha Grande Bay. The tectonic boundary between Paraíba do Sul and Embu Terrains is the main reactivation zone in the Bocaina Ridge. AFT ages of ca. 55 Ma register the initial stage of the SBCR, which produced base level lowering and the formation of an inland scarp. The Bocaina Ridge seems to constitute an elevated region since the development of the Ribeira Cordillera, increased by the South Atlantic rift and post-rift uplifts and also by the SBCR.

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28

Raab, Matthias Johannes. "The geomorphic response of the passive continental margin of northern Namibia to Gondwana break-up and global scale tectonics." Doctoral thesis, [S.l.] : [s.n.], 2001. http://webdoc.sub.gwdg.de/diss/2001/raab/index.html.

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29

Robert, Xavier. "Séquence d'activité des failles et dynamique du prisme himalayen : apports de la thermochronologie et de la modélisation numérique." Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00352596.

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L'influence de l'érosion sur la localisation de la déformation dans une chaîne de montagnes est un phénomène souvent envisagé à la suite de modélisations numériques. Or les données géologiques pertinentes en faveur de cette hypothèse sont encore fort peu nombreuses. Aussi, la mise en évidence d'une évolution temporelle et spatiale de la déformation constitue une observable clef pour tester les relations érosion/localisation de la déformation. Nous testons cet effet, sur un objet géologique soumis à des conditions de déplacements aux limites simples et sur un objet géologique soumis à des conditions climatiques et érosives variables latéralement : le flanc sud de l'Himalaya (située au dessus d'un décollement crustal majeur). Elle est soumise à une convergence continue et de valeur constante depuis au moins une dizaine de millions d'années et sa rhéologie est invariante au cours du temps ; elle est en revanche soumise à un gradient climatique d'est en ouest (transversalement par rapport à la direction de convergence), gradient de plus variable au cours du temps. Nous avons mis en oeuvre des techniques de thermochronologie basse température pour consituer une base de données conséquente, que nous avons utilisée dans des modélisations numériques thermo-cinématiques directes et inverses. Nous montrons que 1) au Népal central,le MHT présente une rampe crustale prononcée, et aucun mécanisme de chevauchement en hors-séquence n'est nécessaire pour expliquer les données, 2) la géométrie du MHT varie d'est en ouest, avec une rampe moins prononcée dans l'est de la chaîne, et 3) les variations latérales en terme de mise en place et de cinétique du MFT sont peu importantes.

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30

Wu, Cheng-Yin, and 吳承穎. "Fission-Track Ages of Apatite from Tachosui gneiss and their Geologic Implications." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/28090862141975998846.

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碩士
國立臺灣大學
地質科學研究所
97
Taiwan is located in a remarkable tectonic setting at the convergence between the Luzon arc and Eurasian plate. In order to understand the thermal history of the northern Tananao Schist of East. Taiwan, since the Penglai Orogeny, a total of nine bedrock samples were collected from the Tachosui Gneiss along the Hopin forest trail as a vertical transect within an area of few km2. The samples were analyzed by fission-track dating technique. The results and the localities of the sub-vertical section allowed us to discuss the relationship between elevation and apatite fission-track ages. The apatite fission-track ages of the nine samples range from 0.6±0.1Ma to 0.3±0.1Ma and display unimodal distributions, implying these bedrock samples were totally annealed during the Penglai Orogny. It suggests that the northern Tananao Schist had been subjected to a higher temperature and then cooled down below the closure temperature of the apatite fission-track system which probably initiated at ~0.6 Ma. The positive correlation between apatite fission-track ages and sampling elevations implied that the bedrock of the studied area was close to exhume steady state. In this study, two different uplift rates of the studied area based on different approaches can be obtained. The denudation rate of 2.2mm/yr was estimated by the difference in elevation divided by the difference in apatite fission-track ages between two samples; the other estimation involves assumption of geothermal gradient and closure temperature which gives uplift rates in the range of 4-9 mm/yr. Combined with the previous zircon and apatite fission-track studies, these data demonstrate that the cooling rates have continuously increased since the Penglai Orogeny. Key word: Tananao schist, Tachosui gneiss, fission track, apatite, denudation rate

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31

Liang, Jia-Hung, and 梁嘉宏. "Zircon and apatite fission Track Dating along the “Lishan Fault” and its tectonic implication." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/45635204996456259089.

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32

Lee, Ting-Yuan, and 李定原. "Fission-track dating of Apatite from the Northern Hsuehshan Range and Four Other Localities, Taiwan." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/43375971389748500069.

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33

Jepson, Gilby Mats Morrison. "The low-temperature tectonic evolution of the Western Tian Shan (Kazakhstan, Kyrgyzstan, Uzbekistan, Tajikistan)." Thesis, 2018. http://hdl.handle.net/2440/118072.

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The evolution of intracontinental mountain ranges represent a unique challenge in our understanding of the Earth’s history. One of the largest of these intracontintal mountain ranges on Earth is the Tian Shan in Central Asia. The crustal architecture of the Tian Shan formed during the closure of the Palaeo-Asian Ocean in the Palaeozoic and underwent multiple reactivations in response to distant tectonic events at the Eurasian plate margin, to give rise to the modern expression of the Tian Shan we see today. Most of the previous thermochronological studies in the Tian Shan focused on the core of the mountain range, deciphering a punctuated tectonic history throughout the Mesozoic, with a dominant Cenozoic overprint as a result of the India-Eurasia collision. However, little work has been done on the eastern and western extents of the Tian Shan. These regions are characterised by low relief and record less Cenozoic overprint, providing opportunity to better constrain the Mesozoic thermo-tectonic history of the Tian Shan. In this project, we used multiple thermochronometers (apatite uranium-lead, zircon (UTh- Sm)/He), zircon fission track, apatite fission track, and apatite (U-Th-Sm)/He) on >100 basement samples taken along the western-most extent of the Tian Shan. More specifically, samples from the Karatau–Talas range in the north (Kazakhstan and Uzebkistan), the Chaktal–Kurama range (Uzbekistan and Tajikistan) and the Kyzylkum–Nurata Segment (Uzbekistan and Tajikistan) in the middle, and the Garm region in the south, were analysed to decipher key periods of deformation and mountain building in the Tian Shan. Initially, the western Tian Shan underwent a period of Triassic–early Jurassic fast-cooling and exhumation interpreted as a response to the collision of the Qiangtang block with the Eurasian margin. Subsequently a period of slow-cooling and denudation during the late Jurassic–Cretaceous was recorded, as the western margin of the Tian Shan experienced a hiatus in reactivation. However, the major suture zones in the western Tian Shan still preserve a signal of late Jurassic–Cretaceous fast-cooling and reactivation, as a possible response to extensional tectonics on the Eurasian margin. Finally, much of the Mesozoic Tian Shan is overprinted by the distal effects of the India-Eurasia collision in the Cenzoic. The India- Eurasia collision, the latest and possibly the largest of the Gondwanan fragments to collide with the Eurasian continent, generated a thermal overprint along faults and generated most of the topography that we see today. Using multiple middle to low temperature thermochronometers, this study attempted to unpack the complex and convoluted evolution of the world’s largest intracontinental mountain range. Showing that it is possible to track the evolution, both spatially and temporally, of such a vast orogen from its ancestral foundation through to the more modern controls of continental growth. Furthermore, it has been possible to apply constraints and unpack the tectonic regimes that influence the growth of an intracontinental mountain range, providing an analogue for the definition of other intracontinetal tectonic settings throughout the globe.
Thesis (Ph.D.) -- University of Adelaide, School of Physical Sciences, 2018

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34

Otasevic, A. "Thermal history of the Junggar Alatau (SE Kazakhstan, NW China): insights from apatite fission track thermochronology." Thesis, 2018. https://hdl.handle.net/2440/133457.

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The Junggar Alatau is located along the border of SE Kazakhstan and NW China, representing the western extent of the northern Chinese Tian Shan within the Central Asian Orogenic Belt. This study applies apatite U–Pb and low temperature thermochronology to constrain the exhumation history of the Junggar Alatau through the Meso-Cenozoic period. Apatite U–Pb results record Ordovician-Permian ages, reflecting the post-magmatic cooling of granitoids that intruded during the progressive closure of the Palaeo-Asian Ocean. Apatite fission track data obtained from Palaeozoic basement and (meta)sedimentary samples record (partial) preservation of post-magmatic cooling ages and suggests at least two subsequent cooling periods during the Late Triassic (~230–210 Ma) and Early Cretaceous (~150–120 Ma). Permian-Triassic cooling signals are preserved in low-relief areas distal to major NW-SE orientated shear zones, reflecting post-magmatic cooling during the Palaeo-Asian Ocean closure and regional exhumation in response to the Qiangtang collision. The Early Cretaceous rapid cooling signal is localised for samples taken along the Central Kazakhstan Fault Zone (CKFZ). The record of younger signals localised in the CKFZ suggests the reactivation of faulting during the Early Cretaceous, which can be linked to a phase of slab-rollback and associated extension in the distant Tethys Ocean. Cretaceous exhumation is thought to have induced rapid cooling in the exhuming footwalls with respect to subsiding hanging walls of the CKFZ. Additionally, few samples from higher relief areas record Late Cretaceous cooling, although there is no consensus on the cause. The results obtained in this study indicate that the extent of Cenozoic exhumation within Central Asia has not propagated to the Junggar Alatau. Results obtained in this work fit with those obtained from samples along other major NW-SE orientated shear zones in the vicinity of the study area, improving the overall understanding of strain propagation through Central Asia.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2018

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35

Lai, Pei-Chi, and 賴斾綺. "Apatite Fission Track Dating of the Fold-and-Thrust Belt in Northern Taiwan and its Tectonic Implications." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/80177431021328993016.

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碩士
國立臺灣大學
地質科學研究所
99
Taiwan mountain belt was resulted from the collision between NE trending continental margin of the Eurasia and N-S trending Luzon arc on Philippine Sea plate.The Philippine Sea plate moves in NW direction that results in an oblique collision and the mountain building propagates southwardly, with a rate of 50-90 km/Ma. This model suggests that the development of the fold and thrust propagates southwardly. With the cessation of active folding and thrusting during the collision, northern Taiwan is now undergoing post-collisional extension, followed by the eruption of the Tatun volcanoes since 2.6Ma. In this study, we examine the fission track systematics of apatites from the fold and thrust belt in northern Taiwan. Forty-one rock samples were successfully collected from the Tertiary sequences but only sixteen of them yield enough apatites with reliable ages. The results show that the reset boundaries of the apatite fission tracks are quite different between the eastern and western sides of the Chushih fault. In the western side, the reset boundary appears in the Miocene Mushan Formation. In contrast, it locates in the Oligocene to Eocene formations on the eastern side. The difference of reset boundary may reflect the thickness difference of the sedimentary sequences on both sides. On the hanging wall the sequence thickness above the Oligocene Formation may have been less than 4~5 km, as reflected by the partial reset ages. By contrast, the resetting boundary is located in the Miocene Mushan Formation, which is much younger than that on the hanging wall, due to the thicker foreland basin deposits. The oldest total reset ages appear to be near 3 Ma from the formations on hanging wall of the Kanchiao fault and Chushih fault, indicating that the fault-and-thrust belt in northern Taiwan may have been developpned at near 3 Ma. This age appears to be similar to that discovered in southern Taiwan. This similarity further implies that the southward propagation model of the fold-and-thrust belt in Taiwan has not gained supports from the fission track data.

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36

Simpson, A. D. W. "The Meso-Cenozoic deformation history of Thailand and Myanmar; insights from calcite U-Pb and apatite fission track thermochronology." Thesis, 2018. https://hdl.handle.net/2440/133682.

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Given the absence of suitable dating methods, the timing of low-temperature crustal deformation is usually established by indirect methods (such as apatite fission track (AFT) thermochronology). Few studies have previously ventured into directly constraining the absolute timing of brittle deformation (such as authigenic illite dating). U-Pb dating of calcite in tectonic veins represents a new method to potentially directly date brittle deformation events (Roberts and Walker, 2016). By utilising this method in combination with apatite U-Pb and fission track thermochronology, this study sheds new light on the upper crustal deformation history of Thailand and Myanmar. U-Pb calcite ages demonstrate tectonic activity at ~216-209Ma in the Khao Kwang Fold and Thrust Belt associated with the Indosinian stage 2 collision between the Sibumasu Block and the Indochina Block. Brittle deformation along the Three Pagodas Fault Zone (TPFZ) was dated at ~45Ma and ~24Ma (and possibly as recently as ~1.3Ma). AFT thermochronology suggests exhumation in the Tin province of southern Myanmar at ~26Ma-18Ma. These dates are in agreement with previous regional AFT studies in Thailand and with calcite U-Pb dates for the TPFZ, suggesting fault reactivation in response to the India-Eurasia collision and rifting in the Andaman Sea. Calcite U-Pb ages were obtained with uncertainties as low as ~1%, which is an unprecedented precision for the timing of brittle deformation. This work further demonstrates that calcite elemental mapping, in combination with U-Pb dating, can be used to distinguish different calcite growth events. Particularly enrichments in Mn or depletions in LREE concentrations in calcite seem useful to distinguish different fluids and associated calcite (re)crystallisation events. Although further work is required to enhance our understanding of both Pb diffusion in calcite as well as geochemical tracers for calcite recrystallization, the combination of calcite U-Pb with apatite fission track thermochronology is a promising novel tool to enhance our understanding of the timing of brittle deformation.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2018

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37

van, der Beek Pieter. "Tectonic evolution of continental rifts. Inference from numerical modelling and fission track thermochronology." Phd thesis, 1995. http://tel.archives-ouvertes.fr/tel-00785951.

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38

HUANG, CHENG-JIA, and 黃承加. "Numerical Simulation of Middle Crustal Flow And Formation of The Danba Anticline: Constrained by Apatite And Zircon Fission Track Ages." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/am5y2k.

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碩士
國立中正大學
地震研究所
104
We applied a finite difference method to simulate the thermal evolution of the Danba Anticline, Sichuan, China. The anticline is located to the northwest of the Sichuan Basin within the Songpan-Ganzi orogen. Because the fold axis of the anticline is subparallel to the direction of the surface compression, buckling is unlikely the mechanism responsible for the growth of the Danba Anticline. We suspect that the formation of the Danba Anticline in Cenozonic period may be related to the middle crustal flow. The sharp change in GPS velocity field near the Sichuan Basin implies that the ductile middle crust materials flow around the relatively rigid Sichuan Basin. As a result, the velocity fields between the upper crust and middle crust are different. In this study, we employed the corner flow model to estimate the velocity and direction of middle crust flow in Danba area. We found that the direction of the middle crust flow is nearly perpendicular to the fold axis of the Danba Anticline. This finding confirms that the growth of the Danba Anticline may result from injection of the middle crust materials, which are driven by the uprising Tibet, beneath the Danba Anticline. We used the apatite and zircon fission track ages across the Danba Anticline as our model constraints. With that we can simulate the thermal history of the Danba Anticline by solving thermo-kinematic equations for detachment folding and calculated the corresponding fission track ages. According to our results, the velocity of middle crust increased with time in Cenozoic (<25Ma), and the thickness of the middle crust channel is about 14 km, the width of the anticline is about 140 km, and the amount of exhumation in the hinge of the Danba Anticline is about 19 km, which agrees with the amount of exhumation (17~26 km) estimated by geobarometry upon a Mesozoic decollement.

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39

Locke, Brian David. "Thermal evolution of the eastern Serrania del Interior foreland fold and thrust belt, northeastern Venezuela, based on apatite fission track analyses." Thesis, 2001. http://hdl.handle.net/1911/17443.

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Apatite fission track data show a gradual decrease in age (∼30 Ma to ∼15 Ma) from north to the south in the eastern SerranIa del Interior, northeastern Venezuela. Based on a previous study, a model for the tectonic evolution of the eastern SerranIa is proposed in which two stages of deformation occurred. Stage 1 (45 Ma--20 Ma) involves the internal deformation of fault blocks. Stage 2 (20 Ma--12 Ma) involves envelopment thrusting, doubling the thickness of the thrust sheet. Shortening within the SerranIa del Interior ceased at 12 Ma. In stage 1, cooling and exhumation rates were 5.8°C/km and 0.26 km/my, respectively, and in stage 2, cooling and exhumation rates were 4.25°C/km and 0.2 km/my, respectively. The deformation of the SerranIa prior to the collision of the Caribbean plate with South America is probably related to the convergence of the North and South American plates.

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40

Sanguinito, Sean Michael. "Investigating the effect of high-angle normal faulting on unroofing histories of the Santa Catalina-Rincon and Harcuvar metamorphic core complexes, using apatite fission-track and apatite and zircon (U-Th)/He thermochronometry." 2013. http://hdl.handle.net/2152/23197.

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The formation and evolution of metamorphic core complexes has been widely studied using low temperature thermochronometry methods. Interpretation of these data has historically occurred through the lens of the traditional slip rate method which provides a singular rate that unroofing occurs at temporally as well as spatially, and assumes unroofing is dominated by motion on a single master detachment fault. Recently, several new studies have utilized (U-Th)/He ages with a higher spatial density and greater nominal precision to suggest a late-stage rapid increase in the rate of unroofing. This analysis is based on the traditional slip rate method interpretation of broad regions of core complexes that display little to no change in age along the slip direction. An alternative interpretation is presented that instead of a change in slip rate, there may have been a change in the style of unroofing, specifically caused by the transfer of displacement from low-angle detachment faulting to high-angle normal faults. Apatite fission-track (AFT), and apatite and zircon (U-Th)/He (AHe and ZHe) analyses were applied to samples from the Santa Catalina-Rincon (n=8 AHe, and n=9 ZHe) and Harcuvar (n=12 AFT, n=16 AHe, and n=17 ZHe) metamorphic core complexes in an attempt to resolve the possible thermal effects of high-angle normal faulting on core complex formation. Samples from the Harcuvars were taken along a transect parallel to slip direction with some samples specifically targeting high-angle normal fault locations. The AFT data collected here has the advantage of improved analysis and modeling techniques. Also, more than an order of magnitude more data were collected and analyzed than any previous studies within the Harcuvars. The AFT ages include a trend from ~22 Ma in the southwest to ~14 Ma in the northeast and provide a traditional slip rate of 7.1 mm/yr, similar to previous work. However, two major high-angle, detachment-parallel normal faults were identified, and hanging-wall samples are ~3 m.y. older than the footwalls, indicating high-angle normal faults rearranged the surface expression of the distribution of thermochronometer ages to some extent. AHe ages range from 8.1 Ma to 18.4 Ma but in general decrease with increasing distance in the slip direction. ZHe ages generally range between 13.6 Ma and 17.4 Ma. A series of unexpectedly young AFT ages (10-11 Ma), given by three complete samples and distinct population modes in others, suggest that some parts of the range underwent a later-stage unroofing event possibly caused by high-angle faulting. Confined fission-track length distributions were measured for Harcuvar samples and modeled using the modeling software HeFTy to infer thermal histories and calculate local cooling rates. These imply a component of steady cooling in some parts of the range, evidence of a different departure from a single-detachment dominated model.
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41

Carrière, Kevin L. [Verfasser]. "Neoproterozoic to Holocene tectonothermal evolution of the southern Cantabrian Mountains NW Iberia, revealed by apatite fission track thermochronology / vorgelegt von Kevin L. Carrière." 2006. http://d-nb.info/980665566/34.

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42

Fernie, Nicholas Stewart. "Thermal History of Central Australia: Cooper Basin, South Australia & Anmatjira Range, Northern Territory: Insights from Apatite Fission Track and U-Pb Thermochronology." Thesis, 2019. http://hdl.handle.net/2440/123092.

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A large number of geological studies around the globe have used radiogenic isotopes in accessory minerals to thoroughly investigate upper and lower crustal processes. Minerals such as zircon, monazite, rutile and apatite are some examples of high and low temperature geochronometers which have been applied to various geological problems. Heavy mineral geochronometers have been commonly used to date high temperature igneous and metamorphic processes. Further developments extended their use to dating the depositional ages of sedimentary successions and being able to make conclusions about sediment provenance. Advances in the more recent fission track method have extended the use of these minerals to low-temperature processes such has heating due to burial and cooling due to uplift allowing scientists to date orogenic systems, brittle fault reactivation and basin development. Advances in LA-ICP-MS technology and double dating apatite for fission track and U-Pb chronometers increases the minerals efficiency and applicability to investigatng multiple temperature ranges on a single sample. This study utilizes apatite as the primary tool to investigate and assessa variety of geological settings. Detrital apatite was sampled from the oil and gas rich Cooper-Eromanga Basin to assess and test Cretaceous heating, charge timing and subsequent late Cretaceous cooling profiles from a number of well bores in the region. In this case time-temperature paths were derived by collecting samples over a vertical profile from a range of present-day downhole temperatures, modelled and compared to the results from previous fission track and vitrinite reflectance studies. Apatite U-Pb from was used to make conclusions about the provenance of the stratigraphic unit from which it was sampled and assessed in conjuction with published zircon U-Pb. A secondary assessment was conducted on the cratonic Anmatjira Range, Central Australia. The stability of cratonic regions around the globe has begun to be brought into question due t1o the development of low temperature thermochronometres. In this case apatite fission track was used to assess the assumed Mesozoic stability of the Palaeoproterozoic differentially metamorphosed granitoids of the Anmatjira Range. The actual cause of Mesozoic cooling in Central Australia remains inconclusive but evidence suggests long-wavelength tectonism from either mantle dynamics or synchronous far field orogenic events. Apatite U-Pb, trace and rare earth element analysis was applied to the same samples to assess the effect that prograding greenschist facies to amphibolite facies metamorphism has on the U-Pb chronometer and diffusion characteristics of Mn, Sr and REEs. The result exhibits significant variations in closure temperature between the measured isotopes, indicating a decoupling between U-Pb chronometers, trace and rare earth elements which could have strong implications for sedimentary provenance. Application of multiple apatite chronological methods gives an indication of the minerals flexibility and can be utilized across a range of geological environments. Through the assessment of apatite behavior from recently deformed basin environments to cratonic metamorphosed granitoids, this study investigates some of the uses apatite has and its possible applications to future chronological studies.
Thesis (Ph.D.) -- University of Adelaide, School of Physical Sciences, 2019

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MERESSE, Florian. "Dynamique d'un prisme orogénique intracontinental : évolution thermochronologique (traces de fission sur apatite) et tectonique de la Zone Axiale et des piémonts des Pyrénées centro‐occidentales." Phd thesis, 2010. http://tel.archives-ouvertes.fr/tel-00772154.

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Ce travail de thèse concerne une transversale complète des Pyrénées centro-occidentales, où on a combiné la thermochronologie basse température (traces de fission sur apatites, TFA) avec une analyse structurale détaillée pour décrire les mouvements verticaux associés à l'évolution du système chevauchant, et pour déterminer l'influence de ce dernier sur le cycle sédimentation/enfouissement/exhumation des dépôts synorogéniques du bassin d'avant‐chaine sud (bassins de Jaca et Ainsa). L'analyse TFA complète les données déjà publiées dans la Zone Axiale et la Zone Nord‐Pyrénéenne, e tconstitue la première étude de ce genre dans un bassin d'avant‐chaîne pyrénéen. Les données TFA sur la transversale du bassin sud‐pyrénéen montrent une diminution vers le sud du degré d'effacement des traces de fission, traduisant la diminution vers le sud de la quantité d'enfouissement, supérieure à 5 km au nord et inférieure à 3 km au sud dans l'hypothèse un géotherme de 25°.km‐1. Le contexte géologique montre que l'enfouissement est principalement lié à l'accumulation des dépôts synorogéniques. Les données TFA de lapartie nord du bassin montrent un refroidissement d'âge Oligocène supérieur‐Miocèneinferieur (moyen). Par ailleurs, une nouvelle interprétation de profils de sismiques réflexiondans le bassin de Jaca montre que le chevauchement d'Oturia s'enracine dans lechevauchement de socle de Bielsa, responsable de l'exhumation tectonique hors‐séquencedu bord sud de la Zone Axiale au Miocène inférieur (‐moyen) (Jolivet et al., 2007). Cesrésultats attestent donc de l'exhumation tectonique hors‐séquence au Miocène inférieur (Burdigalien‐ ?Langhien) de la partie nord du bassin d'avant‐chaine sud‐pyrénéen. Des données TFA obtenues dans la Zone Axiale et la Zone Nord‐Pyrénéenne confirment lamigration générale vers le sud du système chevauchant, et mettent également en évidencela réactivation tectonique hors‐séquence du bord nord de la Zone Axiale à l'Oligocèneterminal‐Miocène inférieur. L'ensemble de ces résultats atteste donc de la réactivation en " pop‐up " de la parties interne des Pyrénées centre‐ouest à l'Oligocène supérieur‐Miocèneinférieur (Burdigalien‐ ?Langhien), postérieurement au scellement du front sud‐pyrénéen (Aquitanien‐ ?Burdigalien) classiquement considéré comme marquant la fin de lacompression pyrénéenne. Ces données nous ont permis de proposer un nouveau modèle d'évolution crustale des Pyrénées centro‐occidentales en 3 grandes étapes : (i) du Crétacé supérieur à l'Eocène moyen, le prisme est caractérisé par une absence de relief, en lien avec l'inversion de structures extensives crétacées conduisant à l'accrétion de petites écailles crustales ; (ii) la période Eocène supérieur‐Oligocène correspond à la collision continentale proprement dite, et est marquée par la création d'importants reliefs associés à l'accrétion d'épaisses unités crustales ; (iii) au Miocène inférieur, la partie interne du prisme pyrénéen est réactivée.

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Reddy, M. C. "Low-temperature thermochronologic insight into the exhumation of the Northern Gawler craton (South Australia)." Thesis, 2014. http://hdl.handle.net/2440/110559.

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The Gawler Craton (South Australia) records a complex thermal history during the Phanerozoic. Previous work has indicated that the central Gawler Craton was largely exhumed during the Carboniferous as a far-field effect of the Alice Springs Orogeny. Besides this widespread exhumation event, localised Mesozoic and Tertiary thermal events have been documented for the central Gawler Craton as well. The extent of these events into the northern Gawler Craton is not well understood as low-temperature thermochronological data is lacking for this region. For this study, granitoid samples along a roughly north-south transect through the northern and central Gawler Craton were analysed using the apatite fission track (AFT) and apatite (AHe) and zircon (ZHe) U-Th-Sm/He methods. Results from these low-temperature methods yield Neoproterozoic through to Cretaceous AFT, AHe and ZHe ages. Cumulative AFT age plots reveal a multi-phase Phanerozoic cooling history for the central and northern Gawler Craton. Significant AFT age peaks were found at ~480-450 Ma and ~350-300 Ma. The Ordovician age peak is thought to be related with the final stages of the Delamerian Orogeny, while the Carboniferous age peak is interpreted as being a far field response to the Alice Springs Orogeny. This is consistent with previous interpretations throughout South Australia. Additionally, localised Jurassic and Cretaceous AFT and ZHe ages were obtained which are thought to be related with rifting at the southern Australian margin and river incision respectively.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2014

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Mansour, El Mehdi. "THERMOCHRONOLOGIE PAR LA METHODE DES TRACES DE FISSION DANS L'APATITE. APPLICATION AUX MASSIFS DE L'ARGENTERA-MERCANTOUR (ALPES OCCIDENTALES) ET DES JEBILET (MESETA MAROCAINE)." Phd thesis, 1991. http://tel.archives-ouvertes.fr/tel-00452094.

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Dans les apatites des roches plutoniques et métamorphiques, les Traces de Fission (TF) de l'Uranium 238 ne commencent à être enregistrées que lorsque la température ambiante est inférieure à environ 130°C. Elles sont conservées quantitativement lorsque cette température se situe au-dessous de 60-70°C. Nous avons utilisé cette propriété pour l'étude de l'histoire de refroidissement de deux massifs hercyniens: l'ArgenteraMercantour (Alpes Occidentales) et les Jebilet (Meseta Marocaine). Après avoir, dans la première partie de ce travail, exposé l'état actuel de la datation par TF et discuté de ses applications et de ses limites pour les apatites, on expose les résultats d'un travail de calibration mené à partir d'irradiations dans trois réacteurs nucléaires: Mélusine (CEN-Grenoble), RHF (ILL-Grenoble) et Orphée (CENSaclay). Dans l'Argentera, 16 échantillons ont été prélevés selon une transversale NW-SE. Les âges TF des apatites correspondantes montrent que le massif s'est refroidi au dessous de 130°C à partir de 10 Ma et que son taux apparent de surrection-érosion entre 10 Ma et 2.8 Ma est resté sensiblement constant, de l'ordre de 0,15-0,20 mm/an. Entre 2,8 Ma et 0,3 Ma, ce taux est passé à 0,6±0,1 mm/an pour le flanc SW et 0,9±0,2 mm/an du côté NE, en accord avec les mouvements différentiels déjà mis en évidence par les données de la géologie. Dans les Jebilet, les 7 échantillons étudiés présentent des âges TF concordants. Le début de l'enregistrement des traces, à 186±6 Ma, concorde avec l'âge de l'ouverture de l'Atlantique Central. II implique un paléogradient géothermique, au Jurassique inférieur, de l'ordre de 55-60°C/km. Le dernier évènement thermique enregistré dans ces minéraux est, à 38±3 Ma, la phase atlasique majeure.

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Trenouth, C. W. "An insight into the lowtemperature thermal evolution of the covered eastern Gawler Craton margin: the Stuart Shelf basement." Thesis, 2015. http://hdl.handle.net/2440/118240.

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Multi-method thermochronology applied to the eastern Gawler Craton, beneath the Stuart Shelf cover (Olympic Dam Domain, South Australia), reveals multiple episodes of exhumation. Modelled data from Apatite Fission Track (AFT) analysis identifies four time periods where the eastern Gawler Craton basement experienced cooling into AFT closure temperatures (~60-120°C); at1050 ± 55 Ma (Mesoproterozoic), 439 ± 14 Ma (late Ordovician-Silurian), 304 ±36 Ma (mid-Carboniferous-mid Permian) and 245 ± 52 Ma (late Permian-early Jurassic). In addition, the Carboniferous and Jurassic peaks are supported by zircon (ZHe) and apatite (AHe) (U-Th-Sm)/ He results. The Ordovician peak is interpreted as resulting from the final pulses of the Delamerian Orogeny partially, mixed with the first pulses of the Alice Springs Orogeny. The Carboniferous-Permian event is linked with widespread exhumation likely due to the final pulses of the Alice Springs Orogeny (~300Ma). The preserved Mesoproterozoic event presents new AFT data in the area and coincides with some recent studies. However, it occurs only in samples obtained from the Gawler Range Volcanics and more prominent in core depth shallower than 500m. The late Permian-early Jurassic event is comparable to events believed have to stemmed from hydrothermal events. This event compliments AFT studies in the northern Flinders Ranges. The Late Ordovician-Silurian and Carboniferous-early Permian AFT pulses confirm events seen in studies of surrounding regions. Other geochronological studies around the Olympic Dam area indicate that this pulse either results from a localised hydrothermal event or distal effects of the Musgravian Orogeny. The Jurassic event suggests that the hydrothermal effect on AFT ages may be a more widespread event and not just localised to the northern Flinders Ranges as previously thought. The Ordovician event represents mixing between Delamerian and Alice Springs Orogenies. The Carboniferous-Permian event represents late distal effects of the Alice Springs Orogeny. These events match those of surrounding regions.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2015

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47

Lelarge, Maria Lidia. "Thermochronologie par la méthode des traces de fission d'une marge passive (dôme de Ponta Grossa, SE Brésil) et au sein d'une chaîne de collision (zone externe de l'arc alpin, France)." Phd thesis, 1993. http://tel.archives-ouvertes.fr/tel-00603209.

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La méthode de datation par les Traces de Fission (TF) sur apatite, géothermomètre sensible aux faibles températures "150°C) s'est révélée être un outil efficace dans l'étude de l'histoire thermique des roches. Elle permet de contribuer à l'établissement d'une thermochronologie des évènements tectoniques (soulèvement, dénudation, basculement des blocs, etc ... ) survenus dans une région donnée, d'apporter de nouvelles contraintes dans l'interprétation des données géologiques et géophysiques connues, et dans une certaine mesure, d'évaluer des taux apparents de dénudation et d'estimer des paléo-gradients géothermiques. La méthode des traces de fission sur apatite est alors susceptible de fournir des renseignements précieux dans des cadres géologiques divers, où les phénomènes géodynamiques peuvent être liés aussi bien à des zones de divergence de plaques litho sphériques qu'à des zones de convergence. Ainsi, à partir des potentialités d'une même méthodologie (méthode des traces de fission), nous nous sommes proposés d'apporter des données nouvelles d'ordre thermo chronologiques dans deux contextes géologiques différents: une marge continentale passive (dôme de Ponta Grossa, Sud-Est du Brésil) et une chaîne de collision (massif de Belledonne, Alpes occidentales Françaises). Ce mémoire est subdivisé en deux parties principales, soit quatre chapitres. Dans le premier chapitre, nous avons tout d'abord présenté les principes généraux de la méthode des traces de fission: les mécanismes susceptibles de créer des traces de fission, les détecteurs solides capables de les enregistrer, les paramètres intervenant sur leur stabilité ainsi que la technique utilisée pour les rendre visibles au microscope optique. Nous avons ensuite rappelé les principes de la datation par TF, sa mise en équation, les modes d'acquisition et de traitement des données, ses domaines d'application et enfin différents modèles permettant d'attribuer aux âges apparents TF une signification géologique. Le deuxième chapitre est consacré à l'exposé des différentes procédures analytiques utilisées dans notre laboratoire, de nos résultats sur la calibration d'une position d'irradiation en réacteur nucléaire ainsi que sur la détermination des paramètres de l'équation d'âge dépendants des conditions opérationnelles adoptées (facteur de géométrie "g" et "zeta"). Le troisième chapitre, est quant à lui dédié à l'application de la méthode des traces de fission à une marge continentale passive. Nous y exposons la contribution de la méthode à la compréhension de l'histoire thermochronologique des roches du socle du dôme de Ponta Grossa et l'implication avec les phénomènes tectoniques de la région. Le quatrième et dernier chapitre, porte sur l'utilisation de la méthode des traces de fission sur apatite dans le cadre de l'étude d'une chaîne de collision. De l'analyse des résultats obtenus sur les roches métamorphiques du massif de Belledonne, nous avons proposé, à partir de nos dormées Traces de Fission sur apatite, un certaine nombre de contraintes pour l' histoire du refroidissement de la région étudiée et son implication avec le contexte tectonique.

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Perez, De Armas Jaime Gonzalo. "Tectonic and thermal history of the western Serrania del Interior foreland fold and thrust belt and Guarico Basin, north central Venezuela: Implications of new apatite fission track analysis and seismic interpretation." Thesis, 2005. http://hdl.handle.net/1911/18800.

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Structural analysis, interpretation of seismic reflection lines, and apatite fission-track analysis in the Western Serrania del Interior fold and thrust belt and in the Guarico basin of north-central Venezuela indicate that the area underwent Mesozoic and Tertiary-to-Recent deformation. Mesozoic deformation, related to the breakup of Pangea, resulted in the formation of the Espino graben in the southernmost portion of the Guarico basin and in the formation of the Proto-Caribbean lithosphere between the diverging North and South American plates. The northern margin of Venezuela became a northward facing passive margin. Minor normal faults formed in the Guarico basin. The most intense deformation took place in the Neogene when the Leeward Antilles volcanic island arc collided obliquely with South America. The inception of the basal foredeep unconformity in the Late Eocene-Early Oligocene marks the formation of a perisutural basin on top of a buried graben system. It is coeval with minor extension and possible reactivation of Cretaceous normal faults in the Guarico basin. It marks the deepening of the foredeep. Cooling ages derived from apatite fission-tracks suggest that the obduction of the fold and thrust belt in the study area occurred in the Late Oligocene through the Middle Miocene. Field data and seismic interpretations suggest also that contractional deformation began during the Neogene, and specifically during the Miocene. The most surprising results of the detrital apatite fission-track study are the ages acquired in the sedimentary rocks of the easternmost part of the study area in the foreland fold and thrust belt. They indicate an Eocene thermal event. This event may be related to the Eocene NW-SE convergence of the North and South American plates that must have caused the Proto-Caribbean lithosphere to be shortened. This event is not related to the collision of the arc with South America, as the arc was far to the west during the Eocene.

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Wolff, Reinhard. "Fluorite (U-Th-Sm)/He thermochronology." Thesis, 2015. http://hdl.handle.net/11858/00-1735-0000-0028-87A4-2.

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