摘要
二叠纪是塔里木盆地演化的一个很重要阶段。在研究塔里木盆地内部岩浆作用的过程中首次发现盆地内部正长岩岩体，其３９Ａｒ－４０Ａｒ年龄为２７７．７±ｌ．３Ｍａ，属于早二叠世。该正长岩为形成于板块内部的碱性正长岩，它与盆地内部的二叠纪玄武岩、辉绿岩岩墙一起构成了一套发育于裂谷性盆地的岩浆岩组合，说明二叠纪时塔里木盆地处于裂谷构造环境。
The Permian Period is an important period for geological evolution of the Tarim basin.The syenite body inside the Tarim basin was first found during the study of magmatism inside the basin, and the isochron age of39Ar-40Ar is 277.7±l.3Ma, being equivalent to the Permian. Through the systematical study of petrology, petrochemical and geochemical characteristics, the author concludes that it is an alkali syenite formed inside plate. The syenite,together with basalt, diabase dyke inside the basin forms a special magmatic rock assemblage that always developed in rift basin. These facts show that the tectonic setting of Tarim basin during Permian was rifting. The discovery of alkali syenite is of importance in the study of the tectonic evolution of the Tarim basin.
出处
《地球化学》
CAS
CSCD
北大核心
1996年第2期121-128,共8页
Geochimica
