A mid-Cretaceous age for the Palmer Land event, Antarctic Peninsula: implications for terrane accretion timing and Gondwana palaeolatitudes

New structural and age data suggest that West Gondwana may have been at lower palaeolatitudes than previously interpreted from Albian sequences in Gondwana marginal suspect terranes. The Palmer Land event, which juxtaposed Mesozoic terranes on the Gondwana margin, deformed granitoids in the southern...

Full description

Bibliographic Details
Published in:Journal of the Geological Society
Main Authors: Vaughan, Alan P.M., Pankhurst, Robert J., Fanning, C.Mark
Format: Article in Journal/Newspaper
Language:unknown
Published: Geological Society of London 2002
Subjects:
Online Access:http://nora.nerc.ac.uk/id/eprint/17478/
http://jgs.geoscienceworld.org/content/159/2/113.abstract
Description
Summary:New structural and age data suggest that West Gondwana may have been at lower palaeolatitudes than previously interpreted from Albian sequences in Gondwana marginal suspect terranes. The Palmer Land event, which juxtaposed Mesozoic terranes on the Gondwana margin, deformed granitoids in the southern Antarctic Peninsula. U–Pb SHRIMP dating of zircons from a microgranite dyke yields a crystallization age of 106.9± 1.1 Ma. This result and re-interpretation of the structural position of another granite pluton date the Palmer Land event, and probable terrane collision, as late Early Cretaceous, and not latest Jurassic as formerly interpreted.