深圳大鹏半岛国家地质公园中生代火山地层的时代讨论

DISCUSSION ON AGE OF THE MESOZOIC VOLCANIC STRATA FROM DAPENG PENINSULA NATIONAL GEOPARK IN SHENZHEN

深圳地区中生代火山地层分布区是我国东南沿海浙闽粤港火山活动带的一个重要组成部分,是我国沿海地区侏罗纪—白垩纪火山地层较有代表性地段,也是研究我国东南沿海侏罗纪—白垩纪火山活动的天然博物馆。近期通过野外观察,测制火山地层剖面,进行锆石同位素激光定年测试,对大鹏半岛国家地质公园中生代火山地层的时代提出新的认识,将原划分为上侏罗统高基坪群划分为早—中侏罗世塘厦组（181.8 Ma？）、中侏罗世吉岭湾组（165.8 Ma）、晚侏罗世梧桐山组（156.9~145.6 Ma）、晚侏罗世—早白垩世七娘山组（146.3~131.0 Ma）、早白垩世官草湖群等。

In recent years,through investigation,field geological survey and the zircon trace element LA-ICP-MS analysis for the volcanic rocks of the Dapeng Peninsula National Geopark in Shenzhen,the authors consider the previous Jurassic Gaojiping Group may be divided into： Lower-Middle Jurassic Tangxia Formation（181.8 Ma？）,Middle Jurassic Jilingwan Formation（165.8 Ma）;Late Jurassic Wutongshan Formation（156.9~145.6 Ma）;Late Jurassic-Early Cretaceous Qiniangshan Formation（146.3~131.0 Ma） and Early Cretaceous Guancaohu Group.The Jurassic-Cretaceous volcanic rock in the Park with more representation,is one of the natural museum of coastal areas of Southeast China to study the Jurassic-Cretaceous volcanic activity.