Please read abstract in the article.https://www.cambridge.org/core/journals/geological-magazinehj2021Geolog

Bumby, Adam John

Grantham, Geoffrey H.

Moabi, Neo Geogracious

The study area is located across the Kalahari Craton-Maud Belt boundary in Dronning Maud Land (DML), Antarctica. The â�¼1100 Ma Maud Belt in the east is situated where the â�¼900-600 Ma East African and â�¼530-500 Ma Kuunga orogenies overlap. The Kalahari Craton cover in the west of the study area comprises â�¼1100 Ma Straumsnutane Formation lavas in Straumsnutane. In Straumsnutane, early â�¼1100 Ma low-grade structures suggest top-to-the-NW deformation. Younger â�¼525 Ma structures suggest conjugate top-to-ESE and-WNW transport under low-grade conditions. Western Straumsnutane and Ahlmannryggen do not show the same complex deformation, the intense deformation being restricted to NE Straumsnutane along the eastern margin of the Kalahari Craton. In Sverdrupfjella, in the east, the Maud Belt is underlain by medium-grade, deformed â�¼1140 Ma supracrustal gneisses and younger intrusions. Four deformation phases in the gneisses comprise D1 + D2 with top-to-the-N and-NW folds, D3 top-to-the-S and-SE folding and D4 brittle faulting. Syn-D3 emplacement of granitoid veins is inferred at â�¼490 Ma. Comparison of the deformation vergence of NE Straumsnutane with western Sverdrupfjella suggests D1 in Straumsnutane is correlatable with D1 + D2 Mesoproterozoic structures in western Sverdrupfjella. D2 deformation in Straumsnutane can be correlated with D3 structures and Cambrian-age granites in Sverdrupfjella. D2 deformation in eastern Straumsnutane and D3 in western Sverdrupfjella are inferred to have occurred in a mega-nappe footwall, implying the Ritscherflya Supergroup cratonic cover in eastern Straumsnutane was partially submerged in the footwall, the mega-nappe formed during Gondwana amalgamation, involving collision between N and S Gondwana in the Kuunga Orogeny, â�¼530-500 Ma ago

Bumby, Adam

The structural evolution of the Straumsnutane and western Sverdrupfjella areas, western Dronning Maud Land, Antarctica: Implications for the amalgamation of Gondwana

UPSpace at the University of Pretoria

The structural evolution of the Straumsnutane and western Sverdrupfjella areas, western Dronning Maud Land, Antarctica : implications for the amalgamation of Gondwana

http://repository.ub.ac.id/220610/1/The_structural_evolution_of_the_Straumsnutane_and_western_Sverdrupfjella_areas_western_Dronning_Maud.pdf

The structural evolution of the Straumsnutane and western Sverdrupfjella areas, western Dronning Maud Land, Antarctica : implications for the amalgamation of Gondwana

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UPSpace at the University of Pretoria