| Resources and environmental issues are chief problems in the 21st century. Resource sustainable development has always been the primary task for earth scientists. With shallow resources getting exhausted, development of deep resources has become an inevitable trend of resource exploration. Exploration methods and techniques are challenges that deep resource development must face, while traditional metal ore prospecting techniques can not meet requirements of the deep mineral exploration. Gravity and magnetic exploration methods have critical limitations in detecting deep metal ores, due to the low vertical resolution and fact that the potential field strength attenuation is in inverse proportion to distance square. Nor is DC electrical prospecting method suitable, owing to shallow detection depth. Electromagnetic exploration method is also limited because of its low vertical resolution in deep areas. Consequently, the development of geophysical technology for wide investigation depth range from 500m to 2000m will be the focus of future mineral resource exploration. Seismic exploration method can be used to solve geological exploration issues in the depth range of 500-2000m.Aiming at seismic exploration technique with great depth and density points for metal mine, this paper expounds the following:1. Brief introduction on present research situation of metal mine seismic exploration, as well as recent development trends of seismic acquisition technology with high density; Systematic discussion on principles and applications of seismic exploration methods and techniques for metal mine.2.Based on exploration with depth up to 2000m and ore scale not less than 50m, generation of seismic wave and design of field geometry system have been studied, and feasible schemes have been provided. Full-wave modeling has been conducted for several ore-body models, with imaging study on forward data.3. Aiming at the subproject“Seismic Method Test for Metal Mine”of the national program“Alternative Resources Exploration in Crisis Mines”, metal mine seismic data processing techniques have been investigated based on“Metal Mine Seismic Exploration in Luohe-Dabaozhuang Region”. A set of practical processing procedure has been formed through analyzing the real data and adopting corresponding measures based on different issues. Specific processing techniques, such as wavelet transform, Radon transform, radial trace transform and curverlet transform, etc. have been applied to eliminate main interference waves in metal mine survey. Relative programs have been written and trial calculations have been conducted on model data and actual data, obtaining very good effects.4. Relationship between scatter wave and reflection wave has been analyzed, and full-wave forward calculations have been conducted on several models containing scatterer. Scattered imaging has been done with the self-developed pre-stack migration programs based on equivalent offset, achieving better results, so that the correct way of processing seismic scatter wave data has been found.5. Based on my special fund project“Study on Seismic Exploration Technique with Great Depth and Density Points for Metal Mine”, the newly introduced 428XL seismic data acquisition system was applied to conduct experiment of methods and techniques at Da-gai-tan lead-zinc mine in Huade country of Inner Mongolia. Through optimization of the observing systems, acquisition of reflection wave and scatter wave has better effects and clearer first break wave can be obtained, which is favorable for accurate inversion on seismic tomography. Different processing techniques have been applied to treat real data with predetermined results. |
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