Tectonic development of late Precambrian to Mesozoic Australia through plate motions possibly influenced by the Earth's rotation

Abstract

During late Precambrian to Mesozoic time an overall northward migration of the locus of east Australian orogeny was complemented by an overall southward migration of the locus of initial rifting in western Australia. Related shifts in dextral and/or compressive strain occurred along a trans‐Australia zone of relative crustal mobility. Palaeomagnetic data show that this overall anticlockwise migration of compressive and tensional tectonic regimes about the continent corresponded to apparent overall clockwise rotation upon the globe by Palaeozoic Australia. We propose that the pattern of Australia's tectonism during late Precambrian to Mesozoic time accords with the episodic application in eastern Australia of major continent‐ward‐directed compressive forces. Such forces, moreover, were directed generally palaeowestward, and relative northward migration of the locus of stress application arose by Australia's apparent clockwise rotation upon the globe.

From the integration of geological and geophysical data we infer that Australia underwent episodes of eastward drift and clockwise rotation during the Palaeozoic. These motions mirror those by Palaeozoic North America; together with ‘palaeontological clock’ data and evidence of broad synchronism in worldwide orogeny they suggest an influence of the Earth's rotation on global tectonism.

Notes

Present address: South Australian Dept of Mines & Energy, P.O. Box 151, Eastwood, S.A. 5063.