| Summary: | This thesis focuses on an examination of the Transantarctic Mountains continental margin, a high-elevation rift flank that has experienced uplift since the Early Cretaceous, driven by various geological processes related primarily to continental thinning, erosion, and mantle dynamics. The Transantarctic Mountains have historically represented a key site where low-temperature thermochronology techniques were applied and discussed. For this reason, a comprehensive revision of published apatite fission-track and (U-Th)/He data has been compiled and numerically analyzed to discriminate spatial and temporal variations along the chain. Much attention has been given to observe landscape patterns that change along the strike of the rift flank, which are correlated with geomorphic metrics and lithospheric properties as proxies for surface and deep-seated geological processes. A deeper investigation into the tectonic evolution of the rift flank was conducted by dating new samples from the Convoy Range sector in southern Victoria Land using apatite fission-track thermochronology. Samples processed for thermochronology purposes were collected (during expeditions performed before this thesis project) along fault zones, together with rock samples prepared for petrographic and geochemical analyses, and detailed structural fault data. New age determinations for hydrothermal events and brittle deformation are linked to oblique rifting in the western Ross Sea, which propagated to the Transantarctic Mountains margin escarpments in the early Miocene. Lastly, the post-middle Miocene tectono-magmatic evolution has been tested using a thermo-mechanical numerical model coupled with a landscape evolution model, conceptualized to study how erosion and sedimentation efficiency may drive decompression melting and deformation in rift basins. The abrupt sediment starvation in the western Ross Sea following climate cooling after the middle Miocene may act as a forcing factor in the increased magmatic production in the McMurdo Volcanic ...
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