| Summary: | The Grenville Orogeny represents a globally pervasive tectonothermal event resulting in the amalgamation of the supercontinent Rodinia between ca. 1.3 and 1.0 Ga. The Grenville Orogen appears to be a continuous collisional orogen connecting Laurentia, Amazonia, Baltica and Kalahari and is generally compared to the modern Himalaya-Alpine orogenic system. Its eastern lateral termination is seen in the Sveconorwegian orogen in Baltica, while on the extreme other end, the Namaqua–Natal–Maud orogenic system, on the periphery of the Proto-Kalahari Craton, represents the western lateral termination along the conjugate Kalahari-Laurentia margin. This study focuses on the Grenville-age orogenic history of the Maud Belt, East Antarctica, and the Sveconorwegian orogen exposed in Caledonian nappe windows, West Norway, with an aim to provide a potentially comprehensive understanding of spatial terminations of the Grenville Orogen with comparison to its modern analogues. The specific goals are (1) to figure out the tectonic evolution and develop a refined tectonic model of the Maud Belt, and thus shed light on the orogenic style of the Grenville-age orogenic system along the margin of the Proto-Kalahari Craton; (2) to determine the extent and distribution of the Sveconorwegian crust, and to test a continental collision vs. accretionary model for the formation and evolution of the Sveconorwegian orogen. These aims are addressed by conducting large-scale regional investigations on geochronology and isotopic (radiogenic and stable) compositions of magmatism and high-grade metamorphism. It has been proposed that the formation of the Namaqua-Natal belt is related to the process of continental collision between Laurentia and the Proto-Kalahari Craton, however, the tectonics of the Maud Belt, which is located perpendicular to the Namaqua-Natal belt, were poorly understood so far. In this study, new zircon U–Pb–Hf–O isotopic data along a regional profile from western to eastern Dronning Maud Land (DML) and the comparison to the Natal ...
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