摘要
音频大地电磁法(AMT)作为应用广泛的地球物理测深方法在北方砂岩及南方硬岩型铀矿勘查中均取得了很好的应用效果。随着铀矿勘探深度的不断增加以及勘探环境中电磁干扰的日益严重,对地下目标体的准确识别成为铀矿勘探研究人员重点关注的问题。基于此,本研究有针对性地开展二维电磁数值模拟,通过建立高、低阻异常体典型模型并对其进行正反演计算,讨论了AMT方法针对不同围岩背景下电阻率不同的电性异常体的探测效果。通过对上述模型响应叠加不同强度的噪音信号,对比噪音强度对探测效果的影响程度。最后通过对上述模型不同条件下反演结果的对比分析,总结了AMT探测效果与异常体埋深、围岩背景电阻率以及噪音强度的关系,为后续AMT方法在不同地区的更好应用及准确解译提供了依据。
Audio frequency magnetotelluric(AMT)method,as a geophysical sounding method widely used in recent years,has achieved good results in uranium exploration of hard rock in the south and sandstone type uranium deposits in the north.With the continuous increase in the depth of uranium exploration and the growing severity of electromagnetic noise interference in the exploration environment,the accurate identification of underground targets has become a key concern for uranium exploration researchers.Based on this,the author carried out two-dimensional electromagnetic numerical simulation.By establishing typical models of high and low resistivity anomalies and conducting forward and inverse calculations on them,the detection effects of the AMT method on different electrica l anomalies under different resistivity backgrounds of surrounding rocks were discussed.By superimposing different intensities of noise signals on the above models,the influence of noise intensity on the detection effect was compared.Finally,through the comparative analysis of the inversion results under different conditions,the relationship between the AMT detection effect of the above typical models and the depth of the anomaly body,noise intensity,and resistivity background of the surrounding rocks was summarized,which provides a basis for the subsequent application and accurate interpretation of the AMT method in different regions.
作者
张濡亮
刘一凡
王恒
ZHANG Ruliang;LIU Yifan;WANG Heng(National Key Laboratory of Uranium Resources Exploration-Mining and Nuclear Remote Sensing,Beijing 100029,China;Beijing Research Institute of Uranium Geology,Beijing 100029,China)
出处
《世界核地质科学》
2025年第6期1282-1290,共9页
World Nuclear Geoscience
基金
核技术研发项目(编号:物H2301-1-4)资助。
关键词
音频大地电磁法
围岩
埋深
探测效果
噪音
AMT
surrounding rock
depth
detection effect
noise
numerical simulation
