Frequency-domain electromagnetic method with ground moving source and its detection effect
WAN Wei1, WANG Zhigang2, LU Yao2
1.School of Geophysics and Measurement-control Technology, East China University of Technology, Nanchang, Jiangxi 330013, China; 2.GME & Geochemical Surveys, BGP Inc., CNPC, Zhuozhou, Hebei 072751, China
Abstract：As the traditional ground frequency-domain controlled-source electromagnetic (CSEM) method uses a single transmitter,large source-receiver distances need to be adopted for observation to obtain large detection depths,which is highly likely to cause a low signal-to-noise ratio of the observed data. This paper attempts to use ground moving sources and achieve the purpose of improving the signal-to-noise ratio of the data by narrowing the source-receiver distance and employing transmitters with different offsets for observation. More-overthe effective detection depth is enhanced by comprehensively using geometric sounding and frequency sounding.The typical one-dimensional layered model is utilized to comparatively analyze the detection effects of the frequency-domain electromagnetic method with ground moving sources, i.e.,the ground frequency-domain MSEM method,and the traditional ground CSEM method.The results show that the MSEM method has a favorable detection effect on common geoelectric models and that it can make up for the disadvantage of the traditional ground CSEM method that it is not sensitive to underground high-resistance layers.Experiments on the proposed method are conducted in a mining area in northeast Jiangxi Province,and the data processing results verify the applicability of the ground MSEM method to solve practical problems.
王绪本,陈进超,郭全仕,等. 沁水盆地北部煤层气富集区CSAMT勘探试验研究[J]. 地球物理学报,2013,56(12):4310-4323.WANG Xuben,CHEN Jinchao,GUO Quanshi,et al. Research of the CSAMT exploration mode and experi-ment for the coalbed methane enrichment region in the North Qinshui Basin[J]. Chinese Journal of Geophysics,2013,56(12):4310-4323.
[2]
STREICH R. Controlled-source electromagnetic approaches for hydrocarbon exploration and monitoring on land[J]. Surveys in Geophysics,2016,37(1):47-80.
[3]
ŠUMANOVAC F,OREŠKOVIĆ J. Exploration of buried carbonate aquifers by the inverse and forward modelling of the Controlled Source Audio-Magnetotelluric data[J]. Journal of Applied Geophysics,2018,153:47-63.
[4]
EDWARDS N. Marine controlled source electromagnetics:principles,methodologies,future commercial applications[J]. Surveys in Geophysics,2005,26(6):675-700.
[5]
ELLINGSRUD S,EIDESMO T,JOHANSEN S,et al. Remote sensing of hydrocarbon layers by seabed logging (SBL):results from a cruise offshore Angola[J]. The Leading Edge,2002,21(10):972-982.
[6]
CONSTABLE S. Ten years of Marine CSEM for hydrocarbon exploration[J]. Geophysics,2010,75(5):75A67-75A81.
[7]
景建恩,伍忠良,邓明,等. 南海天然气水合物远景区海洋可控源电磁探测试验[J]. 地球物理学报,2016,59(7):2564-2572.JING Jian’en,WU Zhongliang,DENG Ming,et al. Experiment of marine controlled-source electromagnetic detection in a gas hydrate prospective region of the South China Sea[J]. Chinese Journal of Geophy-sics,2016,59(7):2564-2572.
[8]
刘勇,李文彬,邓方顺,等. 海洋可控源电磁法深海油藏开采监测仿真[J]. 石油地球物理勘探,2022,57(1):237-244.LIU Yong,LI Wenbin,DENG Fangshun,et al. Simulation of deep-sea reservoir development monitoring using marine controlled-source electromagnetic me-thod[J]. Oil Geophysical Prospecting,2022,57(1):237-244.
[9]
罗延钟,张桂青. 频率域激电法原理[M]. 北京:地质出版社,1988.LUO Yanzhong,ZHANG Guiqing. Principle of Frequency Domain IP Method[M]. Geological Publishing House,Beijing,1988.
[10]
赵宁,黄明卫,申亚行,等. 高阶自适应有限元三维直流电阻率正演方法及其在沁水盆地煤气层压裂监测中的应用[J]. 石油地球物理勘探,2021,56(1):209-216.ZHAO Ning,HUANG Mingwei,SHEN Yahang,et al. Forward modeling of 3D DC resistivity based on high-order adaptive finite element and its application in Qinshui Basin[J]. Oil Geophysical Prospecting,2021,56(1):209-216.
WRIGHT D A,ZIOLKOWSKI A,HOBBS B A. Hydrocarbon detection with a multi-channel transient electromagnetic survey[C]. SEG Technical Program Expanded Abstracts,2001,20:1435-1438.
[13]
薛国强,底青云,王若,等. 多通道瞬变电磁法资料处理方法技术综述[J]. 地球物理学进展,2020,35(1):211-215.XUE Guoqiang,DI Qingyun,WANG Ruo,et al. Overview on data processing methods of multi-channel transient electromagnetic method[J]. Progress in Geo-physics,2020,35(1):211-215.
[14]
王显祥,底青云,邓居智. 多通道瞬变电磁法油气藏动态检测[J]. 石油地球物理勘探,2016,51(5):1021-1030.WANG Xianxiang,DI Qingyun,DENG Juzhi. Reservoir dynamic detection based on multi-channel transient electromagnetic[J]. Oil Geophysical Prospecting,2016,51(5):1021-1030.
[15]
张文伟,底青云,雷达,等. 物探新方法——多通道瞬变电磁法在金属矿勘探中的应用[J]. 黄金科学技术,2018,26(1):1-8.ZHANG Wenwei,DI Qingyun,LEI Da,et al. Multi-channel transient electromagnetic method:a new geophysical method and its application in exploring metallic ore deposits[J]. Gold Science and Technology,2018,26(1):1-8.
[16]
鲁瑶,严良俊,谢兴兵,等. 移动源电磁成像方法研究[C]. 第十一届中国国际地球电磁学术讨论会论文集,2013,139-146.LU Yao,YAN Liangjun,XIE Xingbing,et al. The research of moving source electromagnetic imaging method[C]. Proceedings of the 11th China International Symposium on Geomagnetism,2013,139-146.
[17]
GOLDSTEIN M A,STRANGWAY D W. Audio-frequency magnetotellurics with a grounded electric dipole source[J]. Geophysics,1975,40(4):669-683.
[18]
何继善. 广域电磁测深法研究[J]. 中南大学学报(自然科学版),2010,41(3):1065-1072.HE Jishan. Wide field electromagnetic sounding methods[J]. Journal of Central South University(Science and Technology),2010,41(3):1065-1072.
[19]
王志刚,张林,许健华,等. 时频电磁技术在水力压裂监测中的应用[C]. CPS/SEG北京2018国际地球物理会议暨展览电子论文集,2018,1300-1304.WANG Zhigang,ZHANG Lin,XU Jianhua,et al. Application of time-frequency electromagnetic technology in hydraulic fracturing monitoring[C]. CPS/SEG Beijing 2018 International Geophysical Confe-rence & Exposition Electronic,2018,1300-1304.
[20]
何展翔,王绪本,孔繁恕,等. 时—频电磁测深法[C]. 中国地球物理学会年刊2002——中国地球物理学会第十八届年会论文集,2002,551-554.HE Zhanxiang,WANG Xuben,KONG Fanshu,et al. Time frequency electromagnetic sounding method[C]. Annual Journal of Chinese Geophysical Society 2002——Proceedings of the 18th Annual Meeting of Chinese Geophysical Society,2002,551-554.
赵国泽,王立凤,汤吉,等. 地震监测人工源极低频电磁技术(CSELF)新试验[J]. 地球物理学报,2010,53(3):479-486.ZHAO Guoze,WANG Lifeng,TANG Ji,et al. New experiments of CSELF electromagnetic method for earthquake monitoring[J]. Chinese Journal of Geophysics,2010,53(3):479-486.
[24]
卓贤军,陆建勋,赵国泽,等. 极低频探地(WEM)工程[J]. 中国工程科学,2011,13(9):42-50.ZHUO Xianjun,LU Jianxun,ZHAO Guoze,et al. The extremely low frequency engineering project using WEM for underground exploration[J]. Strategic Study of CAE,2011,13(9):42-50.
[25]
王显祥,底青云,许诚. CSAMT的多偶极子源特征与张量测量[J]. 地球物理学报,2014,57(2):651-661.WANG Xianxiang,DI Qingyun,XU Cheng. Characteristics of multiple sources and tensor measurement in CSAMT[J]. Chinese Journal of Geophysics,2014,57(2):651-661.
[26]
周亚东. CSAMT多偶极子源特征与张量测量研究[D]. 四川成都:成都理工大学,2015.ZHOU Yadong. Characteristics of Multiple Source and Study on Tensor Measurement in CSAMT[D]. Chengdu University of Technology,Chengdu,Sichuan,2015.
[27]
万伟,唐新功,黄清华. 陆地可控源电磁法探测效果的频率响应[J]. 地球物理学报,2019,62(12):4846-4859.WAN Wei,TANG Xingong,HUANG Qinghua. Frequency effect on land CSEM sounding[J]. Chinese Journal of Geophysics,2019,62(12):4846-4859.
[28]
GRAYVER A V,STREICH R,RITTER O. 3D inversion and resolution analysis of land-based CSEM data from the Ketzin CO2 storage formation[J]. Geo-physics,2014,79(2):E101-E114.
[29]
KEY K. 1D inversion of multi-component,multi-frequency marine CSEM data:methodology and synthe-tic studies for resolving thin resistive layers[J]. Geophysics,2009,74(2):F9-F20.
[30]
CONSTABLE S C,PARKER R L,CONSTABLE C G. Occam's inversion:a practical algorithm for gene-rating smooth models from electromagnetic sounding data[J]. Geophysics,1987,52(3):289-300.
[31]
TIKHONOV A N,ARSENIN V Y. Solutions of Ill-posed Problems[M]. Halsted Press,Washington,1977.
[32]
LIU C S,LIN J,ZHOU F D,et al. Unified physical mechanism of frequency-domain controlled-source electromagnetic exploration on land and in ocean[J]. Geophysical Journal International,2013,195(3):1630-1639.
