新疆雪米斯坦火山岩带阿日合拉提地段隐伏断层的物探异常特征

Geophysical anomaly characteristics for buried faults at Arihelati section in Xuemistan volcano rock belt,Xinjiang

新疆雪米斯坦火山岩带铀-多金属矿化受EW向深大断裂控制,因阿日合拉提地段第四系广泛覆盖,依靠野外观察来查明断裂构造位置、产状存在困难。对研究区开展音频大地电磁测深与土壤氡浓度综合测量,断层在反演电阻率断面图上表现为高低阻等值线梯度密集带或相对低阻带,在断层破碎带上方土壤氡浓度出现明显的高值异常,曲线尖峰对应着断层在地表的投影位置。综合分析反演电阻率和土壤氡浓度异常特征,快速地查明了隐伏断层的位置、产状及其深部展布形态,为进一步工作部署提供了参考依据。

The uranium-polymetallic mineralization of the Xuemistan volcanic belt in Xinjiang is controlled by EW-trending deep faults.For its widely covered by Quaternary system,the location and occurrence of fault in the Arihelati section is difficult to be explored with field observation.In this study,a comprehensive measurement of audio magnetotelluric(AMT)and soil radon concentration in the area was made,the fault appeared as a high-low-resistivity contour gradient dense belt or a relatively low-resistivity zone on the inversion resistivity profile,and the soil radon concentration appeared as high value anomalies above the fracture zone,with the curve peak corresponding to the projected position of the fault on the surface.Through the comprehensive analysis of the characteristics of inversion resistivity and soil radon concentration anomalies,the location,occurrence and deep distribution pattern of the concealed fault was identified quickly,which would provide a reference for further work deployment.