陈炜;马昌前;边秋娟;胡远清;龙桃成;喻水林;陈冬明;屠江海;

• 1:中国地质大学研究生院
• 2:湖北省鄂东北地质大队
• 3:中国地质大学地球科学学院
• 4:湖北省地质调查院

摘要(Abstract)：

对西藏得明顶地区叶巴组英安岩进行了锆石SHRIMP的U-Pb测年,获得(192.7±1.3)Ma的年龄值可代表得明顶地区叶巴组的年龄,其形成时代为早侏罗世,与达孜县地区叶巴组火山岩近同期。地质年代学研究和岩石组合特征显示,得明顶地区的叶巴组岩性主要为一套浅变质安山岩、英安岩、流纹岩、酸性凝灰岩夹少量碎屑岩、碳酸盐岩,可分为上、中、下3部分。地球化学特征显示,叶巴组为一套中酸性火山岩,可能是雅鲁藏布江洋向北俯冲、消减的产物,形成于岛弧环境。

关键词(KeyWords)： 早侏罗世;叶巴组;火山岩;年龄;得明顶;西藏

Abstract:

Keywords:

基金项目(Foundation): 中国地质调查局矿产资源补偿费矿产勘查项目(矿调[2005]1-10]

作者(Author): 陈炜;马昌前;边秋娟;胡远清;龙桃成;喻水林;陈冬明;屠江海;

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