HR: 1340h
AN: U33A-0035    [Abstracts]
TI: Testing Inheritance of Nuna Paleogeography Into the Supercontinent Rodinia
AU: * Raub, T M
EM: theresa.raub@yale.edu
AF: Yale University, Kline Geology Laboratory 210 Whitney Ave., New Haven, CT 06511 United States
AU: Evans, D A
EM: dai.evans@yale.edu
AF: Yale University, Kline Geology Laboratory 210 Whitney Ave., New Haven, CT 06511 United States
AB: Apparent Polar Wander paths based on high quality paleomagnetic poles are critical tools for evaluating paleogeographic reconstructions of Precambrian supercontinents. Recently such data have presented challenges to various reconstructions for the Neoproterozoic supercontinent, Rodinia. In light of these challenges it has become increasingly important to refine our understanding of the positions of two of the largest landmasses making up Rodinia, Laurentia and Australia. Laurentia and Australia, connected in various reconstructions of Rodinia without an intervening Grenville-aged orogenic belt, should have inherited such a connection from an earlier supercontinent, Nuna. Although existing Paleoproterozoic APWPs for Laurentia and Australia have appeared to support this inherited connection, revised ages for key poles in the North American path and lack of field tests on key poles from Australia warrant a recomparison of these APWPs. New data from the Wharton Group of the Dubawnt Supergroup in the Western Churchill Province, Canada, help contribute to a better understanding of the Laurentian APWP. Results from the ca. 1755-Ma Pitz rhyolites and associated conglomerates lend preliminary support to the recently published pole by Irving et al. from the Cleaver dykes in northwest Canada. Additional data from the Thelon sandstone, overlying the Wharton Group unconformably, can provideconstraints on this pole position and the succeeding APWP segment. Future work from the Lochness formation of the northern Australian Lawn Hill platform should refine the comparison between Laurentian and Australian Paleoproterozoic APWPs, and allow for better understanding of the paleogeography of Nuna and its transition to Rodinia.
DE: 9330 Australia
DE: 9350 North America
DE: 9619 Precambrian
DE: 8157 Plate motions--past (3040)
DE: 1525 Paleomagnetism applied to tectonics (regional, global)
SC: Union [U]
MN: 2004 AGU Fall Meeting