利用重、磁资料研究于都-赣县矿集区盘古山地区断裂构造及花岗岩体分布

摘要

Pangushan area is an important mining area inYudu-Ganxian ore district in which tungsten and tin formed, and the faults structure and granite body have great influnce in orebody formed in this mining area. The purpose of this study in which the faults struc-ture and granite body distribution of the study area are researched useing gravity and magnetic data is to provide geophysical basis for deep prospecting. We, in this paper, have done the following work: ① the plane position of the faults structure is inferred using the technique of normalizing the total horizontal derivative of vertical derivative of the gravity anomaly; ② the vertical first derivative of gravity anomaly is inversed using Euler deconvolution method, and the average depth of the faults structure is inferred;③the plane po-sition of the granite body is inferred using the vertical first derivative of gravity and magnetic anomalies;④the intersection position of the granite body is inferred using the forward and inversion techniques of 2.5D gravity and magnetic profile data in human-computer in-teraction by RGIS software, and the correctness of interpretation results is verified using borehole data; ⑤ the spatial position of the granite body is showed using the model editing module of 3D gravity and magnetic anomalies area data by RGIS software. The results show that Pangushan area has exposed faults, buried faults, exposed low density and weak magnetic granite body, buried low density and strong magnetic granite body. The granite body distribution is controlled by the faults structure, and the orebody distribution is jointly controlled by the faults structure and granite body.%盘古山地区是于都-赣县矿集区内一个重要的钨锡矿成矿区，研究区断裂构造和花岗岩体与成矿关系密切。利用重、磁资料研究盘古山地区断裂构造及花岗岩体分布，为深部找矿提供地球物理依据。利用重力异常归一化总水平导数垂向导数技术推断断裂构造平面位置；利用欧拉反褶积方法对重力异常垂向一阶导数进行反演计算，推断断裂构造平均深度；利用重磁异常垂向一阶导数技术推断花岗岩体平面位置；利用RGIS软件2．5D重磁剖面人机交互正反演技术推断花岗岩体断面位置，并用钻孔验证解释结果的正确性；利用RGIS软件3D重磁模型编辑模块展示花岗岩体空间位置。研究结果显示盘古山地区既有出露断裂，又有隐伏断裂，既有出露低密度、弱磁性花岗岩体，又有隐伏低密度、强磁性花岗岩体，花岗岩体分布受断裂构造控制，矿体分布受断裂构造和花岗岩体共同控制。