Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Journal of Chengdu University of Technology(Science & Technology Edition)》 2009-02
Add to Favorite Get Latest Update

~(40)Ar-~(39)Ar dating of the orthoclase from the Bugasi syenite body in the Coqen area,Tibet,China

MA Run-ze,SHI He,TAO Xiao-feng,LIU Deng-zhong,HU Xin-weiCollege of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China  
The Bugasi syneite body of the Coqen area belongs to a mid-deep intrusion dominated by medium to medium-coarse grained or medium-coarse porphyroid aegirine-augite syenite.It is located in the west segment of Gangdise and intimately associated with the widespread Miocene potassic volcanics.40Ar-39Ar plateau age and isochronal dating of the orthoclase from the syneite body are(27.14±0.05)Ma and(27.15±0.04)Ma,respectively.They represent the crystalline age of the intrusion.The new data indicate that the Bugasi syneite may be the earliest post-collision ultrapotassic alkaline magmatic rock found around the southern Tibet Plateau so far,and suggest that the Cenozoic post-collision potassic and ultrapotassic magmatism in the Lhasa block should start from 27 Ma B.P.at latest,and likely started from around 30 Ma B.P.rather than 25 Ma B.P.believed now.The obtained results provide more reliable space-time restriction for the future investigation of lithospheric evolution of the southern Tibet Plateau as well as for the comparative study of post-collision magmatic events over the Tibet Plateau.
【Fund】: 中国地质调查局资助项目
【CateGory Index】: P588.122
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved