Authors
Jerome H Guynn, Paul Kapp, Alex Pullen, Matthew Heizler, George Gehrels, Lin Ding
Publication date
2006/6/1
Journal
Geology
Volume
34
Issue
6
Pages
505-508
Publisher
Geological Society of America
Description
The U-Pb and 40Ar/39Ar studies of a unique exposure of crystalline basement along the Jurassic–Early Cretaceous Bangong suture of central Tibet reveal previously unrecognized records of Mesozoic metamorphism, magmatism, and exhumation. The basement includes Cambrian and older orthogneisses that underwent amphibolite facies metamorphism coeval with extensive granitoid emplacement at 185–170 Ma. The basement cooled to ∼300 °C by 165 Ma and was exhumed to upper crustal levels in the hanging wall of a south-directed thrust system during Early Cretaceous time. We attribute Jurassic metamorphism and magmatism to the development of a continental arc during Bangong Ocean subduction, and Early Cretaceous exhumation to northward continental underthrusting of the Lhasa terrane beneath the Qiangtang terrane. We speculate that a Jurassic arc extended regionally along the length …
Total citations
2007200820092010201120122013201420152016201720182019202020212022202320248111981215232929314833644940443213