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Full-Text Articles in Physical Sciences and Mathematics
Archean Geodynamic Conditions Using P-T Constraints Of The East Pilbara Craton Ttgs, Andrew Kody Webb
Archean Geodynamic Conditions Using P-T Constraints Of The East Pilbara Craton Ttgs, Andrew Kody Webb
LSU Master's Theses
We know very little about the tectonic setting present during the Hadean, but based on studies of surviving Hadean zircons, we know that a Hadean protocrust must have been established by at least 4.4 Ga (Kemp et al. 2010), and it must have also been able to accommodate minimum melt conditions (Harrison 2005). Tectonic models for Earth during the Hadean and Archean follow two trends: uniformitarianism and non-uniformitarianism. Uniformitarian models (following the famed geological concept that the present is the key to the past) argue that Hadean zircons and Archean rocks formed via processes akin to modern-style oceanic crust production …
Spatiotemporal Distribution Of The Himalayan Leucogranite: Implications For Mountain-Building As A Function Of Indian Slab Dynamics, Hongcheng Guo
Spatiotemporal Distribution Of The Himalayan Leucogranite: Implications For Mountain-Building As A Function Of Indian Slab Dynamics, Hongcheng Guo
LSU Master's Theses
The Himalayan orogen, as a natural laboratory for continental collision, has attracted intense research attention for decades. However, the question of how the orogen was built is still debated, and potential answers are few when considering how and why along-strike variations of the mountain-building processes occurred. Various tectonic models have been proposed to explain the kinematics of the mountain-building. These models include two dimensional models, such as wedge extrusion (Burchfiel and Royden, 1985; Grujic et al., 1996; Kohn, 2008), channel flow coupled to focused denudation (Beaumont et al., 2001; Hodges et al., 2001), tectonic wedging (Yin, 2006; Webb et al., …
Deciphering Controls On Polyphase Intraplate Deformation In The Ertomiao Region, Lang Shan, North-Central China, Michael Blevins
Deciphering Controls On Polyphase Intraplate Deformation In The Ertomiao Region, Lang Shan, North-Central China, Michael Blevins
LSU Master's Theses
The Ertomiao region of the Lang Shan, China, is located approximately 700 km west of Beijing, in the north-central portion of the North China block. This area is characterized by multiple periods of deformation, including periods of extension and contraction, spanning from Permian through Cenozoic time. This setting provides the structural relationships necessary to decipher the controls of polyphase crustal deformation. During fieldwork key structural observations and crosscutting relationships were established. Beginning with a period of contraction, northeast striking post Jurassic, pre Early Cretaceous (123 ma) thrust faults place Precambrian gneiss (unit PCB) onto Jurassic/Cretaceous sandstone and conglomerate (unit Jr/K). …
Early-Middle Tertiary Deposition In The Corque Syncline, Altiplano Plateau, Bolivia, Brian A. Hampton
Early-Middle Tertiary Deposition In The Corque Syncline, Altiplano Plateau, Bolivia, Brian A. Hampton
LSU Master's Theses
Tertiary age rocks are exposed along north-south trending structures throughout the hinterland Altiplano plateau, central Andes. The east limb of the Corque syncline (SW Bolivia) contains the thickest and most continuous successions of late Eocene–Oligocene age non-marine strata (Potoco Formation) on the Altiplano. The Potoco is up to ~6500 m thick and has continuous exposure >103 km2 making it the thickest and most extensive remnant of the mid-Tertiary Altiplano basin. Basin fill during late Eocene–Oligocene time remains the most rapid and sustained period of deposition since Andean orogenesis, recording a long-term sediment accumulation rate of ~0.5 mm/my. The …