摘要
频率域半航空电磁法能快速助推复杂地区的矿产勘查工作,为复杂地质条件下的找矿难题提供了强有力的技术支撑。该方法作为地球物理勘探领域的一种新兴技术,通过无人机搭载电磁传感器在空中测量垂直磁场,具有高效率、低成本,适用于复杂地形等优点。本文采用非结构化四面体网格实现了频率域半航空电磁法的正演模拟,并基于高斯-牛顿法开展了反演算法研究。在正演程序准确性验证方面,通过构建均匀半空间模型,将三维正演结果与Dipole1D的一维解析解进行对比,二者结果吻合良好,验证了算法的可靠性。在此基础上,本文探讨了发射源位置和飞行高度对垂直磁感应强度的影响。在反演研究中,本文分别对多源模型、双峰模型以及基于云南北衙金矿区地质特征构建的理论模型进行了合成数据反演试算,反演结果均有效恢复了地下异常体的分布特征,表明本文反演方法的可行性与稳定性。本文研究为频率域半航空电磁法在矿产勘查中的实际应用提供了有效的数值模拟支撑,对该技术的进一步推广与发展具有积极意义。
The frequency-domain semi-airborne electromagnetic method(FSAEM)can rapidly advance mineral exploration incomplex regions,providing strong technical support for solving exploration challenges under complicated geological conditions.As an emerging technique in geophysical prospecting,this method utilizes unmanned aerial vehicles equipped with electromagneticsensors to measure the vertical magnetic field in the air,offering advantages such as high efficiency,low cost,and suitability forrugged terrain.In this study,forward modeling of the FSAEM was implemented using an unstructured tetrahedral mesh,and aninversion algorithm was implemented based on the Gauss-Newton method.To verify the accuracy of the forward modeling program,a homogeneous half-space model was constructed,and the 3D forward modeling results were compared with the analytical 1Dsolutions from Dipole1D.The excellent agreement between the two results confirms the reliability of the algorithm.On this basis,theeffects of transmitter position and flight altitude on the vertical magnetic field response were further investigated.For the inversionstudy,synthetic inversion tests were conducted for a multi-source model,a double-peak model,and a theoretical model constructedbased on the geological features of the Beiya gold deposit in Yunnan.The inversion results successfully recovered the distributioncharacteristics of the subsurface anomalies,demonstrating the feasibility and stability of the proposed inversion method.Thisresearch provides effective numerical modeling support for the practical application of the FSAEM in mineral exploration and holdssignificant implications for the further promotion and development of this technology.
作者
吴豪
王堃鹏
杨剑
余长恒
唐煜杰
WU Hao;WANG Kunpeng;YANG Jian;YU Changheng;TANG Yujie(Key Laboratory of Earth Exploration and Information Techniques(Chengdu University of Technology),Ministry of Education,Chengdu 610059,China;Chengdu Center,China Geological Survey(Geosciences Innovation Center of Southwest China),Chengdu 610218,China;Sichuan Resources Group Geophysical Prospecting Institute,Chengdu 610051,China;ShandongUniversity of Science and Technology,Qingdao 266590,China)
出处
《沉积与特提斯地质》
北大核心
2025年第4期870-883,共14页
Sedimentary Geology and Tethyan Geology
基金
国家重点研发计划课题(2023YFB3905004)
四川省科技计划资助项目(2024ZHCG0112)
地球深部探测与矿产资源勘查国家科技重大专项(2024ZD1002100)
国家自然科学基金重点项目(42230311)。
