广域电磁法在隐伏金矿中的应用

相对于传统的电磁法,广域电磁法具有一系列的优点。本文介绍广域电磁法的基本原理、特点及广域视电阻率的定义,并阐述其工作方法,综合剖面与平面测试结果分析广域电磁法查找隐伏金矿的有效性。应用该方法在山东某金矿中查找隐伏金矿,根据该区地质背景、成矿条件和矿区岩石物性特征,遵循已知到未知的原则,由广域视电阻率的分布规律推断低阻局部膨大部位与断裂带,从而间接推断金矿成矿的有利部位。广域电磁法推断的断裂带与已知断裂带位置基本一致,圈定的部分局部膨大部位经开挖证明有金矿存在,结果表明利用广域电磁法查找深部隐伏金属矿是有效的、可行的。

The Application of Wide-Field Electromagnetic Method to Hidden Gold Deposit

Wide-field electromagnetic method has a number of advantages compared to conventional electromagnetic method.This paper introduces the basic principle and characteristics of wide-field electromagnetic method and the definition of apparent resistivity of the wide field,and expounds its work methods and analyzes the validity of wide-field electromagnetic method through cross-section and flat-section test result for finding concealed gold.Application of this method is used to find hidden gold deposit in a gold mine in Shandong.According to the geological background,metallogenic conditions and mine petrophysical characteristics of the area,the principle is followed from the known to unknown.The expanding part of low impedance and the fault zone are deduced from the distribution of wide-area apparent resistivity so as to indirectly have the favorable position of the gold mineralization.The fault zone locations inferred by wider field electromagnetic method is consistent with the locations of the known fault zone.It proves that there is a gold mine exists in some local enlargement sites after excavating.The results show that the using of wider field electromagnetic method to find deep concealed metal ore is effective and feasible.