Granitoids and dykes of the Pine Island Bay region, West Antarctica

Abstract We present geochronological and geochemical data for eight plutonic rocks from five locations in the Pine Island Bay area of West Antarctica, collected during RV Polarstern expedition ANT-XXIII/4. Ar-Ar laser method dating yielded closure temperatures ages of c. 147–98 Ma for dioritic and g...

Full description

Bibliographic Details
Published in:Antarctic Science
Main Authors: Kipf, Andrea, Mortimer, Nicholas, Werner, Reinhard, Gohl, Karsten, Van Den Bogaard, Paul, Hauff, Folkmar, Hoernle, Kaj
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2012
Subjects:
Antarc*
Antarctic Science
Antarctica
Pine Island
Pine Island Bay
West Antarctica
Online Access:http://dx.doi.org/10.1017/s0954102012000259
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102012000259
Description
Summary:Abstract We present geochronological and geochemical data for eight plutonic rocks from five locations in the Pine Island Bay area of West Antarctica, collected during RV Polarstern expedition ANT-XXIII/4. Ar-Ar laser method dating yielded closure temperatures ages of c. 147–98 Ma for dioritic and granitic plutonic rocks and an age range of c. 97–95 Ma for granitoid and trachyandesitic dykes. Major and trace element compositions indicate that all rocks have an I-type subduction-related chemistry. There are no A-type granitic rocks in our dataset, and none are yet reported from the Pine Island Bay area. Our results confirm earlier models of post 100 Ma subduction on this part of the Gondwana margin.

Similar Items