江西田里和浙江游溪韧性剪切带特征及其意义

Characteristics and Significance of Ductile Shear Zone in Tianli, Jiangxi Province and Youxi, Zhejiang Province

本文的测试结果表明，展布在江西广丰的田里岩组白云母４０Ａｒ／３９Ａｒ坪年龄为１０１９±０．９Ｍａ，而分布于浙江江山政棠的游溪岩组的黑云母４０Ａｒ／３９Ａｒ坪年龄为５０１．２±２．２Ｍａ，热事件年龄为１２７Ｍａ。它们是两条较大规模的韧性剪切带，该年龄代表了它们的形成年代。本文还综合分析了区域地质调查资料，它们分属扬子和华南两个构造单元的组成部分。该区的江—绍构造带经历了晋宁期、加里东期、印支期和燕山期多期造山作用。这对华南地壳演化的再认识，具有重要的地质意义。

The result of experiment show that 40 Ar/ 39 Arplateau age of muscovite which is from Tianli petrofabric in Guanfeng county, Jiangxi Province is 1 019± 0.9 Ma, and 40 Ar/ 39 Ar plateau age of biotite which is from migmatite in Youxi petrofabric Jiangshan county, Zhejiang Province is 501.2±2.2 Ma , and the heat event age is 127 Ma. The research shows that they are two larger scale ductile shear zones. The 40 Ar/ 39 Ar plateau ages represent respectively the forming time of Tianli ductile shear zone and Youxi ductile shear zone. According to the age data and regional geological investigation analysis, they belong separately to the part of two tectonic units of Yangtze and south China. It also shows that Jiang-Shao tectonic zone undergoes multiphase orogeny which are Jinning, Caledonian, Indosinian and Yanshanian epoch. It is of geological significance for re-understand again the crust evolution of south China.