Parker法视磁化强度填图方法研究及应用  

Research and Application of Parker′s Method of Magnetization Mapping

作　　者：秦熠 杨宇山[1] 刘天佑[1] 朱丹[1] Qin Yi;Yang Yushan;Liu Tianyou;Zhu Dan(Institute of Geophysics&Geomatics,China University of Geosciences,Wuhan Hubei 430074,China;Sichuan Institute of Coal Field Geological Engineering Exploration and Designing,Chengdu Sichuan 610000,China)

机构地区：[1]中国地质大学地球物理与空间信息学院,湖北武汉430074 [2]四川省煤田地质局地质工程勘察设计研究院,四川成都610000

出　　处：《工程地球物理学报》2020年第6期721-731,共11页Chinese Journal of Engineering Geophysics

基　　金：国家自然科学基金(编号:41674102);宁夏回族自治区重点研发计划项目(编号:2018BFG02012)。

摘　　要：Parker R L.、Oldenburg D W.提出密度界面与磁性界面的正反演法,该方法在频率域计算,计算速度快,是一种连续界面正反演方法。但是受到方法以及资料的限制,前人运用视磁化强度填图法时通常采用单界面无限延深或水平双界面磁性体模型进行反演计算,在地形(或磁性界面)起伏较大的地区往往得不到理想效果。针对这一问题,提出一种起伏双界面模型快速视磁化强度填图的新思路,即结合功率谱分析法反演上下起伏界面深度约束下的快速视磁化强度填图。理论模型计算结果说明,功率谱分析约束下的Parker法视磁化强度填图双界面起伏模型相较于水平界面模型提高了反演结果的精度。将该方法应用于小秦岭地区,圈定了与钼、金成矿密切相关的隐伏中生代花岗岩体11个,预测了成矿有利区域,为后期找矿工作提供了地球物理依据。Parker R L.(1973)and Oldenburg D W.(1974)proposed a forward and inverse method for density interface and magnetic interface.This method is fast in frequency domain calculation and is a continuous interface forward and backward inversion method.However,due to the limitations of methods and data,when using the apparent magnetization mapping method,the previous inversion calculation usually uses the single interface infinite extension or the horizontal dual-interface magnetic body model,and the ideal effect is often not obtained in the area with large fluctuation of topography(or magnetic interface).To solve this problem,this paper proposes a new fast apparent magnetization mapping based on the fluctuating dual interface model,that is,combine it with the power spectrum analysis method to invert the fast apparent magnetization mapping under the constraints of the upper and lower fluctuating interface depths.The theoretical model calculation results show that the Parker method apparent magnetization mapping dual interface fluctuation model under the constraints of power spectrum analysis improves the accuracy of the inversion results compared with the horizontal interface model.This method is applied to the Xiaoqinling area,and 11 concealed Mesozoic granite bodies closely related to the formation of molybdenum and gold are delineated,and favorable areas for mineralization are predicted,which provides a geophysical basis for later prospecting.

关 键 词：视磁化强度填图 Parker法 岩体 小秦岭地区 

分 类 号：P631.2[天文地球—地质矿产勘探]