摘要
青海省柴达木盆地是著名的钾肥生产基地,也是中国盐类矿产的主要产地.以往盐类矿产勘查主要针对第四纪浅部盐类矿产,对第四纪深部及古近纪—新近纪卤水钾矿工作程度较低,资源勘查情况不明.由于盐湖区浅部卤水矿化度较高,会对电阻率类方法造成严重的低阻屏蔽效应,从而影响其探测深度,对于应用地球物理方法造成了极大的局限性.为查明该区深部卤水钾矿资源情况,采用对低阻异常敏感、信号强度大、纵横向分辨率高的瞬变电磁法(TEM),并结合勘探深度较大的大地电磁测深法(MT)对深层卤水钾矿进行探测.勘查结果识别出了相对低阻异常区,经后期钻孔验证,显示探测结果较为可靠,表明TEM、MT两种物探方法应用于盐湖区深层卤水钾矿探测是有效的,揭示了TEM、MT综合物探方法在盐湖区探测深层钾盐资源的良好应用前景.
Qaidam Basin in Qinghai Province is a well-known potash fertilizer production base as well as major producer of salt minerals in China.The previous exploration mainly focused on the Quaternary shallow salt minerals,while the work on the Quaternary deep part and Paleogene-Neogene brine potash deposit was not enough,and the situation of resources is still unknown.Due to the high salinity of shallow brine in salt lake area,the resistivity method will have a serious low resistance shielding effect,thus affecting its detection depth and causing great limitations for application of geophysical methods.To find out the deep brine potassium mineral resources in the area,the transient electromagnetic method(TEM)with high sensitivity to low resistance,strong signal intensity and high vertical-lateral resolution,combined with the magnetotelluric sounding(MT)with large exploration depth,is used to explore the deep brine potassium deposit.The exploration results identify the relatively low resistivity anomaly area,and the detection results are reliable through later drilling verification,indicating that the geophysical methods of TEM and MT are effective in exploration of deep brine potassium deposit in salt lake areas,which reveals good prospects of the two methods in exploration of deep potassium resources in salt lake areas.
作者
何胜
苏世杰
侯利朋
HE Sheng;SU Shi-jie;HOU Li-peng(Qinghai Bureau of Environmental Geology Exploration/Qinghai Provincial Key Laboratory of Environmental Geology,Xining 810008,China;Qinghai Institute of Geological Environment Survey/Qinghai No.906 Engineering Survey and Design Institute,Xining 810008,China)
出处
《地质与资源》
CAS
2021年第5期628-636,共9页
Geology and Resources
基金
青海省地质勘查基金项目“青海省柴达木盆地盐湖整装勘查区淡-卤水过渡区地球物理探测试验”(青国土资矿[2014]57号).
