摘要
本文对秦岭环斑花岗岩带进行了系统的测年工作 ,通过对实测U -Pb ,Rb -Sr ,4 0 Ar/ 39Ar年龄测定结果研究 ,认为 2 10～ 2 17Ma是秦岭造山带主造山阶段结束的时间 ,为秦岭主造山期结束提供了确切的证据 ,具有重要的科学意义 .
The Qinling orogenic belt is a famous continental orogenic belt in the world with signature of multistage and multisystem evolution. It underwent all geological evolutionary processes including preorogenic, climactic orogenic and postorogenic phases But until now, there is still different understanding in the terminal stage of the climactic orogenic phase. Discovery of rapakivi granites distributed in the main suture zone of Qinling orogenic belt (Shangdan tectonic zone) has provided a possibility to solve this important geological problem. It is an indisputable fact that rapakivi granites are regarded as the result of post orogenic magmatism Therefore, the terminal time of the climactic orogenic phase of Qinling belt can be estimated by accurate dating of formation age of the Qinling raprkivi granites Basd on the systematic dating of rapakivi granite belt and analysis of U-Pb, Rb-Sr, 39 Ar- 40 Ar and K-Ar age data in Qinling, we regard 210-217Ma as the termnal time of the Qinling climactic orogenic phase This precise evidence has an important scientific significance in understanding the geological history of the Qinling orogenic belt.
出处
《高校地质学报》
CAS
CSCD
1999年第4期372-377,共6页
Geological Journal of China Universities
基金
国家自然科学基金!(编号
4 9672 111
4 973 182 )资助项目
