Abstract:In recent years, non-seismic exploration has played a guiding role in the study of igneous rocks, deep-seated results, and fractures in western Sichuan, especially in the extraction and fine inversion of weak anomaly information by the time-frequency electromagnetic (TFEM) method, which has a good effect in searching for volcanic conduits and exploring the forming mechanism of volcanic rocks. However, the non-plane wave effect, sha-dow effect, and the additional effect of the artificial field source result in the multi-solutions to the data inversion, which leads to the low quality of inversion data imaging or even false anomalies. Multi-component electromagnetic data inversion is an effective method to overcome the difficulties mentioned above. On the basis of the principle of time-frequency electromagnetic exploration, the finite-difference forward modeling formula for the nine-point finite-difference structure of the two-dimensional model and three-dimensional source was derived. According to the principle of regularization inversion, a multi-component joint inversion objective function was constructed, and a multi-component joint inversion algorithm suitable for the time-frequency electromagnetic method was derived. To balance the difference in the order of magnitude between different components, we added the dynamic equilibrium coefficient to the inversion process. The theoretical model test results show that the multi-component joint inversion is more effective than single-component data inversion, and the noisy model test results indicate that the algorithm is correct and reliable and has great anti-noise performance. This method was applied to the observed time-frequency data from western Sichuan, and the inversion results were in good agreement with drilling information and other known information, which shows that the algorithm is practical and effective.
郭鸿喜, 曹杨, 何宇霖, 王轶, 杨俊, 邝锡汉. 时频电磁法多分量联合反演及在川西火成岩勘探中的应用[J]. 石油地球物理勘探, 2022, 57(2): 452-458.
GUO Hongxi, CAO Yang, HE Yulin, WANG Yi, YANG Jun, KUANG Xihan. Multi-component joint inversion for time-frequency electromagnetic (TFEM) method:A case study of igneous rock prospecting in western Sichuan. Oil Geophysical Prospecting, 2022, 57(2): 452-458.
马新华,李国辉,应丹琳,等.四川盆地二叠系火成岩分布及含气性[J].石油勘探与开发,2019,46(2):216-225.MA Xinhua,LI Guohui,YING Danlin,et al.Distribution and gas-bearing properties of Permian igneous rocks in Sichuan Basin,SW China[J].Petroleum Exploration and Development,2019,46(2):216-225.
[2]
马新华,杨雨,张健,等.四川盆地二叠系火山碎屑岩气藏勘探重大发现及其启示[J].天然气工业,2019,39(2):1-8.MA Xinhua,YANG Yu,ZHANG Jian,et al.A major discovery in Permian volcanic rock gas reservoir exploration in the Sichuan Basin and its implications[J].Natural Gas Industry,2019,39(2):1-8.
[3]
张光荣,张宇生,赵晓红,等.时频电磁在川西南部火山岩勘探中的初步探索[C].中国石油学会2019年物探技术研讨会论文集,成都,2019,1044-1047.ZHANG Guangrong,ZHANG Yusheng,ZHAO Xiaohong,et al.Time-frequency electromagnetic (TFEM) method in volcanic rock exploration in southwestern Sichuan[C].Proceedings of 2019 Geophysical Exploration Technology Seminar of China Petroleum Society,Chengdu,2019,1044-1047.
[4]
何展翔,王绪本.油气藏电性异常模式与电磁法油气检测[J].石油地球物理勘探,2007,42(1):102-106.HE Zhanxiang,WANG Xuben.Geo-electrical anomalous pattern of reservoir and oil/gas detection by electromagnetic survey[J].Oil Geophysical Prospecting,2007,42(1):102-106.
[5]
HE Z X,HU W B,DONG W B.Petroleum electromagnetic prospecting advances and case studies in China[J].Surveys in Geophysics,2010,31(2):207-224.
何展翔,陈忠昌,任文静,等.时频电磁(TFEM)勘探技术:数据采集系统[J].石油地球物理勘探,2020,55(5):1131-1138.HE Zhanxiang,CHEN Zhongchang,REN Wenjing,et al.Time-frequency electromagnetic (TFEM) method:data acquisition system and its application[J].Oil Geophysical Prospecting,2020,55(5):1131-1138.
[8]
ZHAO Z,HE Z X,LI D C,et al.Detecting favorable oil and gas targets with time-frequency electromagnetic method-case studies[C].72nd EAGE Confe-rence and Exhibition Incorporating SPE EUROPEC 2010,2010.
[9]
NABIGHIAN M N.Electromagnetic methods in applied geophysics:volume 1:theory[M].Society of Exploration Geophysicists,Tulsa,Oklahoma,1988.
[10]
傅良魁.电法勘探教程[M].北京:地质出版社,1983.
[11]
陈明生,闫述,石显新,等.二维地质体的瞬变电磁场响应特征[J].地震地质,2001,23(2):252-256.CHEN Mingsheng,YAN Shu,SHI Xianxin,et al.Time-domain behavior of transient electromagnetic field for 2D model[J].Seismology and Geology,2001,23(2):252-256.
[12]
王若,王妙月,卢元林.三维三分量CSAMT法有限元正演模拟研究初探[J].地球物理学进展,2007,22(2):579-585.WANG Ruo,WANG Miaoyue,LU Yuanlin.Preliminary study on 3D3C CSAMT method modeling using finite element method[J].Progress in Geophysics,2007,22(2):579-585.
[13]
陈小斌,胡文宝.有限元直接迭代算法及其在线源频率域电磁响应计算中的应用[J].地球物理学报,2002,45(1):119-130.CHEN Xiaobin,HU Wenbao.Direct iterative finite ele-ment (DIFE) algorithm and its application to electromagnetic response modeling of line current source[J].Chinese Journal of Geophysics,2002,45(1):119-130.
[14]
LI Y G,KEY K.2D marine controlled-source electromagnetic modeling:part 1-an adaptive finite-element algorithm[J].Geophysics,2007,72(2):WA51-WA62.
[15]
KEY K.1D inversion of multicomponent,multifrequency marine CSEM data:methodology and synthetic stu-dies for resolving thin resistive layers[J].Geophysics,2009,74(2):F9-F20.
[16]
CONSTABLE S C,PARKER R L,CONSTABLE C G.Occam's inversion:a practical algorithm for generating smooth models from electromagnetic sounding data[J].Geophysics,1987,52(3):289-300.
王若,王妙月.可控源音频大地电磁数据的反演方法[J].地球物理学进展,2003,18(2):197-202.WANG Ruo,WANG Miaoyue.Inversion method of controlled source audio-frequency magnetotelluric data[J].Progress in Geophysics,2003,18(2):197-202.
[19]
王若,王妙月.一维全资料CSAMT反演[J].石油地球物理勘探,2007,42(1):107-114.WANG Ruo,WANG Miaoyue.Inversion of 1-D full CSAMT data[J].Oil Geophysical Prospecting,2007,42(1):107-114.
[20]
何梅兴,胡祥云,陈玉萍,等.CSAMT奥克姆一维反演的应用[J].工程地球物理学报,2008,5(4):439-443.HE Meixing,HU Xiangyun,CHEN Yuping,et al.Application of 1D Occam's inversion to CSAMT[J].Chinese Journal of Engineering Geophysics,2008,5(4):439-443.
[21]
邱卫忠,闫述,薛国强,等.CSAMT的各分量在山地精细勘探中的作用[J].地球物理学进展,2011,26(2):664-668.QIU Weizhong,YAN Shu,XUE Guoqiang,et al.Action of CSAMT field components in mountainous fine prospecting[J].Progress in Geophysics,2011,26(2):664-668.
[22]
王志刚,何展翔,覃荆城,等.时频电磁技术的新进展及应用效果[J].石油地球物理勘探,2016,51(增刊1):144-151.WANG Zhigang,HE Zhanxiang,QIN Jincheng,et al.Advances of TFEM technique and its application[J].Oil Geophysical Prospecting,2016,51(S1):144-151.
[23]
何展翔,胡祖志,王志刚,等.时频电磁(TFEM)技术:数据联合约束反演[J].石油地球物理勘探,2020,55(4):898-905.HE Zhanxiang,HU Zuzhi,WANG Zhigang,et al.Time-frequency electromagnetic (TFEM) technique:step-by-step constraint inversion based on artificial fish swarm algorithm[J].Oil Geophysical Prospecting,2020,55(4):898-905.