粤北下庄矿田坪田花岗岩外接触带型铀矿找矿潜力预测

Prospecting Potential Prediction of Granite Outer Contact Zone Type Uranium Deposit of Pingtian in Xiazhuang Ore Field of Northern Guangdong

粤北下庄铀矿田坪田花岗岩外接触带型铀矿床,矿体主要赋存于粤北贵东岩体的外接触带变质砂岩中,受北北东向构造、热液活动、岩性及接触带共同控制。运用流体包裹体测温测试分析方法,对该地区铀矿体成矿期均一温度和流体盐度进行测试,测试结果:含铀包裹体均一温度范围为150.0℃~252.0℃,流体盐度为0.411~4.857 wt%NaCl eqv,属于中低温、低盐度活动范围。坪田地区热液活动具有多期次性、含矿构造发育、围岩蚀变强烈及低温、低盐度的含矿流体特征,是铀成矿有利的地质条件,也是下庄铀矿田开展花岗岩外带型铀矿找矿潜力较大的重要地区之一。

The Pingtian granite outer contact zone type uranium deposit in Xiazhuang uranium ore field,northern Guangdong Province,mainly exists in metamorphic sandstone of outer contact zone of Guidong rock mass,which is controlled by NE-trending structure,hydrothermal activity,lithology and contact zone.The homogenization temperature and fluid salinity of uranium ore bodies in this area were tested by the method of fluid inclusion temperature measurement and analysis.The test results show that the homogenization temperature of uranium-containing inclusions is 150.0℃~252.0℃,and the fluid salinity is 0.411~4.857 wt%NaCl eqv,which belongs to the range of low temperature and low salinity.The hydrothermal activity in Pingtian area is characterized by multiple stages,ore-bearing structure development,strong alteration of surrounding rock,low temperature and low salinity,which is a favorable geological condition for uranium mineralization and one of the important areas with high potential for granite out-belt type uranium prospecting in Xiazhuang uranium ore field.