Research And Application Of CSAMT In The Deep Mineral Exploration

As the country increased demand for mineral resources, the domestic shallowreserves of mineral resources can not meet the needs of national construction. Theproblem of mineral resources is related to the strategic issues of national economicand social development. Deep mineralization theoretical studies by domestic andforeign geologists show that, Chinese mainland deep bears great potential mineralresources. Development and utilization of the mineral resources of the deep will bemore conducive to economic construction and social development. However, due tothe interference of ambient noise, the complex geological structure of the deep anddeep detection limit of the level of technology and other factors, deep exploration ofmineral resources technology is facing enormous challenges.Controlled audio-frequency Magnetotelluric method (CSAMT) is anelectromagnetic sounding method which is use of the electrical properties of rocksand minerals difference resistance, and observes response to electromagnetic fieldswhich are generated by an artificial source in the earth. CSAMT is exploration depth,high efficiency, small topographic effects, Sensitive to the low resistivity andfrom the high resistivity shield, and high resolution. It is widely used in the deep solidore body mineral exploration in recent years and develops very quickly.First of all, the paper described the research background and research status of thecontrolled source audio-frequency Magnetotelluric method; then introduced theCSAMT method basic theory and field work methods. For the CSAMT data distortionand its correction problems encountered in practical work, a detailed analysis of thecauses of the near-source effect, static effects, source data distortion effects, andnumerical simulation by means of contrasts discuss data correction of the distortioneffect.Finally, the paper takes the CSAMT exploration applications in wudaolingmolybdenum ore as example, based on geological data, the physical properties ofrocks and minerals based on mining gravity and magnetic exploration results, analysisand investigate the electrical inversion of CSAMT profile for the division ofmagmatic intrusions spatial location, to determine tendency of the depth faults, thelocation and depth of wall rock alteration, and the initial division strata.The following conclusions of the CSAMT method in mineral exploration in the deep.1, CSAMT can be used for making a distinction among mining, powerdifferences exist anomalous body of rock, formation structure, alteration zones, andachieving indirectly prospecting.2, Combined with geological gravity and magnetic data, the CSAMT profile canbe made a finer division, to help build a3D geological model.3, The CSAMT can be able to meet the needs of the resolution of deep mineralexploration; in the near zone electric field is more stable than the deep measuredeffect of the magnetic field, and used for near-field distortion correction of data.4, The CSAMT is in various forms, and summarized in essentially non-planareffects, charge effects.