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业已证实地面电法地球物理技术在如下三个方面间接地为勘探提供了有价值的信息: ①追踪硫化物矿化带②圈定拉矿构造或与矿有关的构造③蚀变带填图。若硫化物矿化与金矿共生,通常可用激发极化法(IP)加以圈定,该技术能够探测占体积总量小于0.2%的黄铁矿,有时还可以从石墨和粘土异常中分辨出黄铁矿体,对于构造和蚀变带填图,常常是用可控源音频磁大地电流法(CSAMT),因为这个方法有极好的横向分辨能力和垂向穿透率。典型的CSAMT的探测对象包括:硅化沉积与火山岩、断层、角砾岩带、泥质蚀交、粘土和石墨层,以及其它岩性。为了在贵金属勘探中有效地应用地球物理方法,必须注意以下几项:第一,勘探学家必须准确地划分勘探阶段;第二,勘探学家必须清楚地了解采用地球物理方法所能查明的“示踪”矿化或围岩地质蚀变的类型;第三,正确地选择解决问题所需方法技术(电法、磁法、重力和地震等),提供成功解决问题的最好机会;第四,勘探学家必须有足够的财力去进行适当的地球物理工作,只要认真和充分地应用这些原则,地球物理方法可在降低勘探成本的同时,大大地提高勘探的成功率。
Ground-based geophysical techniques have proven to provide valuable information indirectly for exploration in the following three areas: (1) tracking of sulfide mineralization zones (2) delineation of ore-bearing structures or ore-related structures, and (3) alteration zone mapping. If sulphide mineralization is symbiotic with the gold, it can usually be delineated by IP, which detects pyrite, which accounts for less than 0.2% of the total volume, and sometimes resolves yellow from graphite and clay anomalies Iron ore bodies, for structural and alteration zone mapping, are often controlled by a source-controlled magnetic-earth current method (CSAMT) because of the excellent lateral resolution and vertical transmittance of this method. Typical CSAMT targets include silicification and volcanics, faults, breccia zones, muddy erosion, clay and graphite layers, and other lithologies. In order to effectively use geophysical methods in precious metal exploration, the following must be noted: First, explorationists must accurately classify the exploration phase; second, exploration scientists must have a clear understanding of what geophysical methods can Third, the correct choice of methodological techniques for solving problems (electrical, magnetic, gravity, earthquakes, etc.) provides the best chance of a successful solution to the problem Fourth, exploration scientists must have sufficient financial resources to carry out appropriate geophysical work. As long as these principles are seriously and fully applied, geophysical methods can greatly reduce exploration success while reducing exploration costs.