Cretaceous magmatism and lithospheric extension in Southeast China

A new compilation of reliable isotope age data indicates that Cretaceous magmatism in SE China occurred in four major episodes during 136-146 Ma, 122-129 Ma, 101-109 Ma and 87-97 Ma. A-type granitic and within-plate basaltic magmatism from 140-90 Ma suggests a dominant extensional environment in the region. Voluminous coeval high-K calc-alkaline rocks, which have geochemical features similar to those formed in continental back-are and post-collision extension settings, are interpreted to have been generated in response to lithospheric extension. Cretaceous magmatism, NNE-trending wrench faulting and formation of extensional basin systems favour an extensional tectonic regime in SE China at that time, which was probably similar to present-day Basin and Range Province in the western US. (C) 2000 Elsevier Science Ltd. All rights reserved.