粤东丰顺地区中生代火山活动旋回划分  

Division of Mesozoic Volcanic Cycles in the Fengshun Area,Eastern Guangdong Province

作　　者：李瑞 王建荣 凌恳 曾钧跃 胡弦 朱世博 LI Rui;WANG Jian-Rong;LING Ken;ZENG Jun-Yue;HU Xian;ZHU Shi-Bo(Guangdong Geological Survey,Guangzhou 510080,China)

机构地区：[1]广东省地质调查院,广州510080

出　　处：《华南地质》2021年第1期29-44,共16页South China Geology

基　　金：中国地质调查局“南岭成矿带中西段地质矿产调查”子项目:广东1∶5万丰顺县幅、坪上幅、五经富幅、揭阳县幅区域地质调查(DD20160032-14)。

摘　　要：本文以丰顺地区出露的大套中生代高基坪群中酸性火山岩为研究对象,重新厘定火山岩岩石地层单位自下而上为热水洞组、水底山组和南山村组。高精度LA-ICP-MS锆石U-Pb定年结果显示,热水洞组和南山村组锆石年龄分别介于150±2.1~163.3±1.9 Ma和145.8±1.9~146.6±1.7 Ma,属晚侏罗世。结合野外接触关系、岩性岩相组合和锆石U-Pb年代学将高基坪群划分为两个旋回,水底山组作为其划分标志,代表着区域喷发间断。The Mesozoic Gaojiping Group intermediate-acid volcanic rocks are widely exposed in the Fengshun area and redefined as Reshuidong,Shuidishan and Nanshancun Formations from bottom to top.LA-ICP-MS zircon U-Pb dating results show that the ages of the Reshuidong and Nanshancun Formations are 150±2.1-163.3±1.9 Ma and 145.8±1.9-146.6±1.7 Ma,respectively.According to the field contact relationship,lithology and lithofacies association and zircon U-Pb geochronology,the Gaojiping Group is subdivided into two cycles,and the Shuidishan Formation indicates a regional eruption discontinuity and can be regarded as the subdivision mark of volcanic cycles.

关 键 词：中生代火山岩 锆石U-PB年龄 喷发旋回 粤东丰顺地区 

分 类 号：P688.14[天文地球—地质学]