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Title: The Athabasca Granulite Terrane and Evidence for Dynamic Behavior of Lower Continental Crust
Deeply exhumed granulite terranes have long been considered nonrepresentative of lower continental crust largely because their bulk compositions do not match the lower crustal xenolith record. A paradigm shift in our understanding of deep crust has since occurred with new evidence for a more felsic and compositionally heterogeneous lower crust than previously recognized. The >20,000-km 2 Athabasca granulite terrane locally provides a >700-Myr-old window into this type of lower crust, prior to being exhumed and uplifted to the surface between 1.9 and 1.7 Ga. We review over 20 years of research on this terrane with an emphasis on what these findings may tell us about the origin and behavior of lower continental crust, in general, in addition to placing constraints on the tectonic evolution of the western Canadian Shield between 2.6 and 1.7 Ga. The results reveal a dynamic lower continental crust that evolved compositionally and rheologically with time.  more » « less
Award ID(s):
1255277
PAR ID:
10255433
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Annual Review of Earth and Planetary Sciences
Volume:
46
Issue:
1
ISSN:
0084-6597
Page Range / eLocation ID:
353 to 386
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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