Constraints for Kalaharis position in Rodinia as derived from detrital zircon studies in highgrade metasedimentary rocks from Dronning Maud Land, East Antartica

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The Kalahari plate is rimmed by a Mesoproterozoic orogenic belt, the Namaqua-Natal-Maud Belt, that documents high-grade metamorphism and continent-continent collision between c. 1090 and 1060 Ma. A major part of Dronning Maud Land in East Antarctica is part of the Kalahari plate at 1000 Ma. Two very different reconstructions for Kalahari have recently been proposed. One interprets Kalahari as an indenter into Laurentia, the other places Kalahari along Western Australia. Both, in eastern Laurentia (the Grenville Orogen) and in Western Australia, the occurrence of c. 1080 Ma high-grate rocks would conform with a continent-continent collision with Kalahari at c. 1080 Ma. However, neither structural nor paleomagnetic data unequivocally resolve whether Kalahari collided with one or the other. In Western Australia, only a very narrow strip of c. 1080 Ma old rocks is preserved, the Pinjarra Orogen, the major portion of which probably dismembered by later rifting. Thus, if Kalahari was ever attached to Western Australia, Mesoproterozoic sedimentary rocks in Dronning Maud Land close to any Neoproterozoic suture zone in Dronning Maud Land shoud indicate a typical Australian zircon age population. In this project therefore, detrital zirkons from metasedimentary rocks in Dronning Maud Land will be dated in order to test whether Kalahari collided with Laurentia, Western Australia or neither of these.