Abstract In an effort to reduce the shale gas exploration risks and costs, we applied the wide-field electromagnetic method (WFEM), because of its strong anti-interference capability, high resolution, ability to conduct exploration at large depths, and high efficiency, to the Bayan Syncline in the South Huayuan block, Hunan Province. We collected rock samples and analyzed their resistivity and induced polarization (IP) and built A series of two-dimensional models for geological conditions to investigate the applicability of WFEM to different geological structures. We also analyzed the correlation between TOC of shale and the resistivity and IP ratio to determine the threshold for identifying target formations. We used WFEM to identify the underground structures and determine the distribution, depth, and thickness of the target strata. Resistivity, IP, and total organic carbon were used to evaluate the shale gas prospects and select favorable areas (sweet spots) for exploration and development. Subsequently, drilling in these areas proved the applicability of WFEM in shale gas exploration.
This study was financially supported by the Thirteenth Five-Year-Plan Major Project "Marine Shale Gas Exploration and Evaluation over Laifengxianfeng and Hefeng Block" (No. 2016ZX05034004-004) and China Huadian Engineering Co., LTD (No. CHEC-KJ-2014-Z10).
Cite this article:
. Application of a wide-field electromagnetic method to shale gas exploration in South China[J]. APPLIED GEOPHYSICS, 2017, 14(3): 441-448.
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