Long term structural development and landscape evolution of eastern Dronning Maud Land, and implications for the geological evolution of the Weddell Sea region

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This proposal applies for the funding of fieldwork in Sør Rondane/ eastern Dronning Maud Land (DML) during the expedition “GEA II” in 2011/12, and subsequent isototpe-geochemical and thermochronological research. Sør Rondane is located at a key position where the still unknown suture between East and West Gondwana is presumed to pass through DML. It also occupies a crucial position at the Karoo-Maud Plume between Antarctica, Africa/ Madagascar and India/ Sri Lanka, and therefore represents a key locus for our understanding of the Gondwana breakup history, the opening of the South Atlantic Ocean, and the establishment of the present plate configuration. Structural mapping, isotope geochemistry and geochronology (U-Pb SHRIMP and LA-ICP-MS, Ar-Ar) will be used to gain a better knowledge on the geodynamic evolution of the basement rocks and to detect the position of the E-W-Gondwana suture. Thermochronological methods (fission track/ FT and (U-Th-Sm)/He) and structural analyses of brittle fault zones will be applied to investigate the Phanerozoic shallow crustal dynamics of eastern DML. The regional paleo-isotherm pattern will provide constraints on the geological/ paleogeographic setting of DML within Gondwana, the Gondwana breakup history and regional passive margin evolution, and the long-term landscape and climate evolution of DML within the Antarctic continent. Moreover, the subglacial geology will be investigated by an aerogeophysical survey in combination with ground-geophysical studies in order to trace rock units and tectonic structures on a regional scale.