CSAMT测量在林西县曹家营子地区铀矿勘查中的应用

通过地质调查工作在曹家营子地区发现了较好的铀矿化信息,但地表覆盖严重,构造形迹不明显,主控矿构造不清晰,赋矿层位发育情况不明确,无法揭露铀矿化异常与断裂之间的关系。本次研究在该矿区选用了勘探深度范围大、分辨率高、地形影响和高阻层的屏蔽作用小的可控源音频大地电磁测深法(CSAMT)来了解地层和断裂展布及往深部延伸情况。本文论述了CSAMT的基本原理和工作方法,根据地质资料布设了5条北西向CSAMT剖面,通过应用Occam算法对CSAMT实测数据进行二维反演计算,结合研究区地质特征和岩石电阻率资料,推断解译了5条剖面的岩性垂向分布及断裂空间展布情况。通过ZK1、ZK2、ZK3、ZK4钻探验证,查证了4条断裂的存在并揭露到4段工业铀矿体。本次找矿成功案例为合理运用物探方法寻找铀矿提供了借鉴,同时预示了该地区深部及外围具有很大的找矿前景。

Application of CSAMT survey in uranium exploration in Caojiayingzi area of Linxi County

Good uranium mineralization information was found in the Caojiayingzi area through geological survey work, but the surface coverage is serious, the structure is not obvious, the main controlling ore structure is not clear, the development of the ore-bearing horizon is not clear, and it was impossible to reveal the relationship between uranium mineralization anomalies and faults. This time, the sound source magnetotelluric sounding method (CSAMT) with a large exploration depth range, high resolution, low topographical influence, and controllable shielding e.ect of high-resistance layers was selected in this mining area to understand the formation and depth distribution. This article .rst discusses the basic principles and working methods of CSAMT. Based on geological data, .ve NW-trending CSAMT pro.les are laid out. The Occam algorithm is used to perform two-dimensional inversion calculations on the CSAMT measured data, combined with the geological characteristics of the study area and rock resistivity data. Inferred and interpreted the vertical distribution of lithology and the spatial distribution of faults in 5 sections. Through ZK1, ZK2, ZK3, and ZK4 drilling veri.cation, the existence of 4 faults was verified and 4 sections of industrial uranium ore bodies were exposed. This successful case of prospecting provides a reference for the rational use of geophysical prospecting methods to .nd uranium deposits, and at the same time indicates that the deep and peripheral areas of this area have great prospects for prospecting.