摘要
笔者报道了运用LA-ICP-MS锆石U-Pb方法对云南个旧地区碱性岩侵入年龄和煌斑岩的测年结果,即白云山碱性岩的形成时代为76.6±3.6Ma,煌斑岩的形成时代为77.2±2.4Ma,这两种类型的岩石均为燕山晚期岩浆作用的产物。结合区域地质地球物理资料、岩石学组合的构造指示意义及前人的有关其他研究成果,认为这些岩石形成于岩石圈伸展的动力学环境。
This paper report the LA-ICP-MS zircon U-Pb age data of the alkaline rocks and lamprophyres in the Gejiu tin district, Yunnan Province. Combined with the character of local geology and geophysical of this area, authors try to discuss the geodynamic setting of western Cathaysia block during Late Yanshan epoch. The dating data shows the alkaline rocks formed at 79.9 Ma and the age of lamprophyre is 82.0 Ma, both of which emplaced during late Yanshanian epoch. Based on the previous geophysical profile, tectonic evolution, and the data achieved this time as well as the rock formation we propose that the Gejiu giant tin deposit formed in an extensional setting in Late Yanshanian epoch.
出处
《中国地质》
CAS
CSCD
2008年第6期1138-1149,共12页
Geology in China
基金
国家重点基础研究发展计划项目(2007CB411405、2007CB411407)
中国地质调查局地质大调查项目(1212010634001)
“斯伦贝谢科技研究计划项目(SLBX0804)”资助
作者简介
程彦博，男，1983年生，博士生，矿物学、岩石学、矿床学专业；E-mail：chamboll@126.com。
