• 责任者：Ma Runze (College of Earth Sciences ; Chengdu University of Technology ; Chengdu 610059 ; China) ; Shi He
• 刊名：Journal of Chengdu University of Technology
• 出版年：2009
• 卷期：36(2)
• 关键词：syenites ; 氩—氩计时 ; Ar-Ar dating ; 西藏 ; Tibet
• 页码：p.172-176
• 图表：3 illus., 1 table, 28 refs.
• 分类号：0801
• issnNo：ISSN1671-9727
• isbnNo：CN51-1634/N

MARGIN: 0cm 0cm 0pt" class=MsoNormal>man">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.  man">The new data indicate that the Bugasi syneite may be the earliest post-collision ultrapotassic alkaline magmatic rock found around the southern Tibetan 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 results provide more reliable space-time restriction for the future investigation of lithospheric evolution of the southern mas-microsoft-com:office:smarttags" />Tibetan Plman">ateau as well as for the comparative study of post-collision magmatic events over the Tibetan Plateau.mas-microsoft-com:office:office" />