Thursday, 30 August 2007
4.PS-109
A comparative provenance study of the late Mesoproterozoic Maud Belt (East Antarctica) and Pinjarra Orogen (Western Australia): implications for a possible Mesoproterozoic Kalahari-Western Australia connection
Anna K. Ksienzyk1, Joachim Jacobs1, Jan Kosler1, and Keith N. Sircombe2. (1) Department of Earth Science, University of Bergen, Allegaten 41, Bergen, 5007, Norway, (2) Onshore Energy and Minerals Division, Geoscience Australia, Cnr. Jerrabomberra Ave & Hindmarsh Drive, Canberra, ACT 2601, Australia
The Maud Belt (East Antarctica) and the Pinjarra Orogen (Western Australia) are both late Mesoproterozoic orogens which formed during continent-continent collision. Based on paleomagnetic data, recent Rodinia models suggest a collision between Kalahari and Western Australia along a combined Maud Belt/Pinjarra Orogen. Although attempts have been made to support this model with geochronological data, the size of the available data sets is as yet insufficient to allow statistically sound conclusions. In this contribution, we present new ca. 950 detrital zircon ages (LA-ICPMS and SHRIMP) from the Maud Belt and Pinjarra Orogen. Whereas samples from the Maud Belt show a clear Kalahari signature, metasediments of the Northampton Complex (Pinjarra Orogen) were probably derived from sources within Australia and the adjacent Mawson Craton. A direct comparison between both regions shows significantly different age distributions and no clear evidence for a Kalahari-Western Australia connection.