摘要
广德县山北地区位于下扬子地块皖南褶断带绩溪穹褶断束北缘,属于典型的花岗岩型铀矿(化)分布区.为研究该地区的铀矿(化)分布特征,寻找隐伏铀矿体,本文通过开展地面伽玛能谱、可控源音频大地电磁测深(CSAMT)、土壤氡气等综合物探方法,有效地发现与成矿有关的地球物理异常,结合地质资料,推断了与矿化体有关的岩体接触带和构造发育情况,圈定找矿靶区,并于后期开展的钻探验证工程中辅以伽玛测井定量确定异常铀矿化分布情况.研究结果表明,地面伽玛能谱测量能有效圈定与铀成矿有关的异常靶区;可控源音频大地电磁测深垂向分辨力高,能较准确探测花岗岩体厚度,推断断裂构造发育情况;土壤氡气测量能准确指示深部铀矿化信息.因此合理选用多种物探方法有助于提高地质找矿效果.
The Shanbei area is located in the north margin of the lower Yangtze block, belonging to the typical distribution area of granite type uranium deposit. In order to study the distribution characteristics of uranium deposits in this area, this project is looking for potential hidden uranium deposits. By carrying out comprehensive geophysical exploration methods such as ground gamma spectra, Controlled Source Audio Magnetotelluric Sounding(CSAMT)and soil radon,it can effectively detect geophysical anomalies related to mineralization. Combined with geological data, this work has identified the rock contact zone and tectonic development related to the mineralization body, delineated the prospecting target area, carried out the drilling verification project, and quantitatively determined the uranium mineralization situation by gamma logging. The results show that Ground gamma spectrometry can effectively delineate abnormal target areas related to uranium mineralization. CSAMT has high vertical resolution and can accurately detect the thickness of granite mass and infer the development of faults. Soil radon measurements can accurately indicate deep uranium mineralization information. It is helpful to improve the effect of geological prospecting after selecting several geophysical prospecting methods rationally.
作者
周乾
许强平
何金华
杨彪
谢忠泉
吴姿颖
ZHOU Qian;XU Qiang-ping;HE Jin-hua;YANG Biao;XIE Zhong-quan;WU Zi-qing(Anhui Nuclear Exploration Technology Central Institute,Wuhu 241000,China;No.327 Geological Team,Bureau of Geology and Mineral Resources of Anhui Province,Hefei 230011,China)
出处
《地球物理学进展》
CSCD
北大核心
2019年第5期1980-1987,共8页
Progress in Geophysics
基金
安徽省公益性地质调查基金项目(2016-g-1-9)资助
关键词
地面伽玛能谱
可控源音频大地电磁测深
土壤氡气
花岗岩型铀矿
断裂构造
Ground gamma spectrometry
Controlled Source Audio Magnetotelluric Sounding(CSAMT)
Soil radon
Granite type uranium ore
Fracture structure
