Himalayan-type indenter-escape tectonics model for the southern part of the late Neoproterozoic–early Paleozoic East African– Antarctic orogen

The East African–Antarctic orogen is one of the largest orogenic on the planet. It resulted from the collision of various parts of –East and West Gondwana during late Neoproterozoic–early time (between 650 and 500 Ma). We propose that the part of this Himalayan-type orogen can be interpreted in of a lateral-escape tectonic model. Modern Gondwana reconstructions that the southern part of the East African– orogen can best be reassembled when a number of microplates (the Falkland, Ellsworth-Haag, and Filchner blocks) are between southern Africa and East Antarctica. This microplate is unusual. The microplates probably represent -zone–bounded blocks, produced by tectonic translation lateral escape, similar to those currently evolving in Southeast . One of the escape-related shear zones is exposed as the 20-km-wide Heimefront transpression zone in western Dronning Land. Coats Land, a crustal block within the orogen, probably a block of older crust that was not subjected to reworking ca. 500 Ma by lateral tectonic escape. southern part of the orogen is also typified by very large of late-tectonic A2-type granitoids, intruded ca. 530–490 , probably as a consequence of delamination of the orogenic and the subsequent influx of hot asthenospheric mantle during escape. Erosional unroofing of the orogen is documented the remnants of originally massive areas covered by Cambrian– molasse-type sedimentary rocks throughout Africa, , and Antarctica, testifying to the past extent and size of this of orogens.