Induced polarization in a 2.5D marine controlled-source electromagnetic field based on the adaptive finite-element method
Xu Kai-Jun1 and Sun Jie1
This work was supported by the National Natural Science Foundation of China (No. 41304094) and the National High Technology Research and Development Program of China (863 Program) (No. 2012AA09A20107).
Abstract：
The induced polarization (IP) in rocks and minerals is of significance to the marine controlled-source electromagnetic (CSEM) field. We propose an adaptive finite-element algorithm for the 2.5D frequency-domain forward modeling of marine CSEM that considers the induced polarization. The geoelectrical model is discretized using an unstructured triangular elemental grid that accommodates the complex topography and geoelectrical structures. We use the Cole–Cole model to describe the IP and develop a complex resistivity forward modeling algorithm. We compare the simulation results with published 1D model results and subsequently calculate the electromagnetic field for variable azimuth sources, IP parameters, and topography. Finally, we analyze the IP effect on the marine CSEM field and show that IP of oil reservoirs and topography affects the marine CSEM electromagnetic field.
. Induced polarization in a 2.5D marine controlled-source electromagnetic field based on the adaptive finite-element method[J]. APPLIED GEOPHYSICS, 2018, 15(2): 332-341.
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2018, Vol. 15 
