High resistivity reservoir identification based on synthetic-sources marine controlled-source electromagnetic data
Li Pan1, Li Yuguo1,2
1. School of Geosciences, Ocean University of China, Qingdao, Shandong 266100, China; 2. Key Laboratory of Submarine Geosciences and Prospecting Technology, Ministry of Education, Ocean University of China, Qingdao, Shandong 266100, China
Abstract：In shallow water areas,the marine controlled-source electromagnetic (CSEM) method faces challenges because the air wave from the air-sea interface interacts with signals from the seabed and dominates the electromagnetic responses,which makes it difficult to acquire signals and improve the ability to identify resistance reservoirs.The synthetic-source processing based on radar field synthetic aperture can be used to highlight high resistivity anomaly of thin beds and identify high resistivity reservoirs.In this paper,we discuss the source-interference method of marine CSEM field.We first calculate normalized amplitude,effective anomaly,and detectivity for 1D model,and compare their identification of high resistivity reservoirs.Then we calculate the normalized amplitude,effective anomaly,detectivity for 2D marine model,and the detectivity of synthetic sources for 3D model.Finally,we apply the proposed method to real data.The examples show that the detectivity can improve high-resistivity reservoir identification on synthetic-source marine CSEM data.
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