重磁方法在国内外金属矿中的研究进展

Review of the gravity and magnetic methods in the exploration of metal deposits

重磁勘探技术是国内外发展最早的查找多金属矿体的地球物理方法,其以多金属矿体与围岩之间的密度或磁性差异为物理基础,对密度和磁性差异较大的地质体分辨能力强.随着仪器设备的发展,航空重磁测量技术使地形陡峭地区的测量成为了可能,其勘探深度大、效率高、工作限制条件较少等优点也越来越受到物探工作者的关注.通过重磁勘探可以直接对致矿目标体进行勘探,也可用于圈定断裂和岩体的空间分布,查明成矿相关地质构造和划分构造单元等,为勘探金属矿起到关键的指示作用.在过去的几十年里,重磁勘探技术在国内外大量的金矿、铜矿、铁矿等有色多金属矿产的勘探发现中起到了至关重要的作用.本文主要对重磁勘探在金属矿勘察方面的原理、仪器、数据处理方法、反演解释及其应用的进展进行了比较全面的论述,总结了未来高精度重磁测量和数据处理技术方面的发展前景.

The Gravity andmagnetic methodsare the first geophysical techniques to be used in metal deposit exploration. These methods are very useful for any targets for which there is a strong density or magnetic contrast at depth. A steady progression in instruments and field operations,especially the airborne platform has enabled the acquisition of gravity and magnetic data in nearly all environments,even on the areas with extremely steep topography. These techniques has become more and more popular for geophysicists because of the significantly improvements in data accuracy,field efficiency and exploration depth. The gravity and magnetic methodsnot only are employed to explore the mental mineral deposits, but also are particularlyuseful in regional geological mapping of favorable terranes for the occurrence of metal deposits,as well as to identify appropriate structures and rock types that host metal deposits. In the past half century,these two methods played very important roles in the exploration of many types of metal ore bodies,such as gold,copper,and iron deposits and so on. This study reviewed the continuous evolution of gravity and magnetic methods in the basic theory,instruments,field operations,data processing techniques,methods of interpretation and applications,and summarized their development prospect infuture.