1D forward modeling for marine borehole electromagnetic
Feng Xukui1,2, Wang Kunpeng3, Cao Hui1, Lan Xing4
1. Key Laboratory of Earth Exploration and Information Technology, Ministry of Education, Chengdu University of Technology, Chengdu, Sichuan 610059, China;
2. BGP Inc., CNPC, Zhuozhou, Hebei 072750, China;
3. School of Geophysics and Information Technology, China University of Geosciences (Beijing), Beijing 100083, China;
4. Sichuan Shutong Geotechnical Engineering Company, Chengdu, Sichuan 610000, China
Abstract:Placing a borehole vertical bipole source into a metal case of oil drilling well and supplying alternating current is a new cheap method to detect the underground dynamic conductor and monitor the seafloor oil-gas method. This method has gradually drawn attention in internationally. We place a borehole vertical bipole into a marine metal case of oil drilling well and derive the electromagnetic response expression of vertical dipole in one dimensional marine stratiform medium. We disperse the finite line source into a number of finite vertical dipole so that we can simulate the whole line source though superimposing electromagnetic response of every single vertical dipole because of principle of superposition. Besides, we design deep sea, shallow sea model and the mode which under the reservoir has un-known reservoir. We obtain one dimensional forward simulation results when bipole is placed in deep sea and shallow sea respectively. The results show that the special mode of this method is very useful and accurate for prospecting oil and gas in deep sea. Meanwhile this method also has little disturbance from air wave and has real meaning for Chinese marine oil and gas development.
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