摘要
老爷庙地区位于东准噶尔东部,是中亚造山带的重要组成部分。老爷庙流纹岩与典型A型花岗岩相似,成因类型上属A2型流纹岩,产于后碰撞环境。锆石U-Pb定年显示其形成于(311. 6±3. 1) Ma,属晚石炭世。综合文中数据及区域地质特征,老爷庙地区在晚石炭世已经拼贴到西伯利亚板块,进入后碰撞向板内转化的过渡期,结束了该区洋陆过渡环境。
Laoyemiao area is located in east of east Junggar, known as the important tectonic metallogenic belt of the Central Asian Orogenic Belt. Laoyemiao rhyolite is similar to the typical A-type granite,and the genetic type belongs to A2-type rhyolite, which is produced in post-collision environment. Zircon U-Pb dating shows that it was formed at( 311. 6 ± 3. 1) Ma in the Late Carboniferous. Based on the data and regional geological features,Laoyemiao area has been planted into the Siberian plate in the Late Carboniferous,entering the transition period from the post-collision to the intraplate transformation,and put an end to the ocean-land transition environment.
引文
[1]熊双才,张征峰,李广,等.东准噶尔老爷庙地区碱性花岗岩锆石U-Pb定年、地球化学及其地质意义[J].地质论评,2019,65(1):221-231.XIONG Shuangcai,ZHANG Zhengfeng,LI Guang,et al.Zircon U-Pb dating,geochemical characteristics of alkaligranites in Laoyemiao Area,Eastern Junggar,and geological significance[J].Geological Review,2019,65(1):221-231.(in Chinese with English abstract)
[2]WHALEN J B,CURRIE K L,CHAPPELL B W.A-type granites:geochemical characteristics,discrimination and petrogenesis[J].Contributions to Mineralogy and Petrology,1987,95(4):407-419.
[3]EBY G N.Chemical subdivision of the A-type granitoids:petrogenetic and tectonic implications[J].Geology,1992,20(7):641-644.
[4]PEARCE J A,HARRIS N B W,TINDLE A G.Trace element discrimination diagrams for the tectonic interpretation of granitic rocks[J].Journal of Petrology,1984,25(4):956-983.
[5]KING P L,WHITE A J R,CHAPPELL B W,et al.Characterization and origin of aluminous a-type granites from the Lachlan Fold Belt,southeastern Australia[J].Journal of Petrology,1997,38(3):371-391.
[6]张祺,金惟俊,李承东,等.再论花岗岩按照Sr-Yb的分类:标志[J].岩石学报,2010,26(4):985-1015.ZHANG Qi,JIN Weijun,LI Chengdong,et al.Revisiting the new classification of granitic rocks based on whole-rock Sr and Yb contents:Index[J].Acta Petrologica Sinica,2010,26(4):985-1015.(in Chinese with English abstract)
[7]史建杰,陈宣华,丁伟翠,等.中亚造山带西准噶尔晚古生代洋陆转换与构造演化--来自晚石炭世流纹岩的证据[J].地质力学学报,2017,23(1):150-160.SHI Jianjie,CHEN Xuanhua,DING Weicui,et al.Late paleozoic ocean-continent transition in West Junggar,Central Asian Orogenic belt:evidence from late carboniferous rhyolites[J].Journal of Geomechanics,2017,23(1):150-160.(in Chinese with English abstract)