安徽铜陵舒家店铜矿三维音频大地电磁探测研究

摘要

Audio-frequency magnetotelluric method and 3D inversion code were used to study the porphyry copper deposit in Shujiadian, Tongling, Anhui Province. A 3D inversion was demanded. Sites data were selected and frequencies were decided, and the WSINV3DMT code was used with a reasonable parameter design to obtain the 3D conductivity structure. The electrical characteristics and structure framework of the 3D model were discussed by slices of the model with different depths and orientations. The results show that 2D/3D characteristics for the deep structure of the region are obvious. The model is proved to be high in precision by comparison between the observed data and the model response. Combined with the discussion of properties of the main geological body, the deep low resistivity anomaly between the high resistivity rock mass may be the reflection of altered rock or the ore body.%利用音频大地电磁法,对安徽省铜陵矿集区舒家店斑岩型铜矿床进行三维探测研究.对经过预处理的实测AMT数据利用相位张量进行维性分析;通过挑选适当的测点和频域数据,设计合理的参数,利用WSINV3DMT程序进行实测AMT数据3D反演,得到舒家店铜矿床的3D电性模型;利用模型响应与实测AMT数据的拟合对比对反演结果进行评价;利用不同深度、不同方向的空间切片讨论3D反演模型的电性结构特征.研究结果表明:该区深部2D/3D构造特征明显;所选反演模型整体精度较高,仅部分局部精度低;深部与代表岩体的高阻体相间共存的低阻体异常极可能是蚀变岩体或直接是矿体的反映.