NUMERICAL MODELING OF GEOELECTRICAL TIME-LAPSE MONITORING SUBSURFACE
LUO Wei-bin, LI Qing-chun
Western Mineral Resources and Geological Engineering Key Laboratory of Ministry of Education, Department of Geophysics, Chang'an University, Xi'an 710054, China
Based on finite-element numerical modeling, the authors studied the feasibility of applying the resistivity method to monitoring underground geological variations. A time-lapse subsurface monitoring method based on geoelectrical observations is proposed in this paper. The numerical modeling result using 2D resistivity forward and inversion program shows that the relative variation of resistivity can serve as a good indicator for resistivity changes both regionally and locally. High-precision and large quantities of data observations of earth resistivity constitute the foundation of time-lapse subsurface monitoring. With the well-performed 2D or 3D resistivity modeling and inversion, this technique makes geo-electrical survey a useful time-lapse monitoring subsurface method.
[1] Zhou B,Dahlin T.Properties and effects of measurement errors on 2D resistivity imaging surveying [J].Near Surface Geophysics, 2003: 105-117.
[2] Yaramanci U.Geoelectric exploration and monitoring in rock salt for the safety assessment of underground waste disposal sites [J].Journal of Applied Geophysics ,2000,44:181-196.
[3] 李金铭.地电场与电法勘探 [M].北京:地质出版社,2005.
[4] Wright D,Ziolkowski A,Hobbs B.Hydrocarbon detection and monitoring with a multicomponent transient electromagnetic (MTEM) survey [J].The Leading Edge,2002(September):852-864.