Characteristics and Mechanism of the Dangra Yun Co and Xuru Co NS-Trending Graben in the Gangdese, Tibet
CAO Sheng-hua
LI De-wei
YU Zhong-zhen
XU Zu-feng
TANG Feng-lin
Abstract：The Dangra Yun Co and Xuru Co NS-trending graben located at central section of the Gangdese, is controlled by NS-trending high-angle normal faults and consists of the Dangqung Co. Dangra Yun Co and Xuru Co. Miocene alkati volcanic rock distributed along the graben indicates an intraplate extensional tectonic environment by its petrochemical and geochemical analyses. A 12. 6 Ma age is determined for leucite phonolite by the K-Ar method, and it is found that graben occurred at the late time of Miocene (about 13 Ma), and remained active until Holocene. There are Middle Pliocene to Holocene lacustrine deposits in the graben. The Dangra Yun Co and Xuru Co graben, as well as other NS-trending grabens, is the results of extension of upper crust driven by the thermal upderplating of the lower crust flowing and thickening. S-N extension became E-W extension with the change of flow direction in the lower crust.
Keywords：NS-trending grabenstructural geologyLate CenozoicDangra Yun Co and Xuru Cothe Qinghai-Tibet plateau.
Publication Date：2009-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 914-920 )