Antarctic Peninsula continental magnesian andesites: indicators of ridge-trench interaction during Gondwana break-up

Subduction of young, hot oceanic lithosphere and a major episode of lithospheric extension have been considered as key tectonomagmatic factors in the genesis of ‘Setouchi-type’ continental magnesian andesites. We present data on a new discovery of such andesites from the northern part of the Antarctic Peninsula and propose that subduction of newly created oceanic lithosphere occurred along the proto-Pacific margin of Antarctica during the Middle Jurassic. Continental magnesian andesite magmatism was contemporaneous with the early stages of Gondwana break-up and we suggest that subduction of young, hot oceanic lithosphere and ridge-trench interaction may have contributed to the disintegration of Gondwana by thermally weakening the lithosphere and developing a broad, linear extensional zone along the proto-Pacific margin.

Details

Publication status:
Published
Author(s):
Authors: Alabaster, Tony, Storey, Bryan C.

Date:
1 July, 1990
Journal/Source:
Journal of the Geological Society / 147
Page(s):
595-598
Digital Object Identifier (DOI):
https://doi.org/10.1144/gsjgs.147.4.0595