1D joint inversion of frequency-domain and time-domain MCSEM data in marine shallow waters
(2.Key Laboratory of Exploration Technologies for Oil and Gas Resources, Yangtze University, Ministry of Education, Wuhan, Hubei, China 430100)
(3.Mengcheng National Geophysical Observatory, Mengcheng, Anhui, China 233500)
【Abstract】1D forward modeling of marine electromagnetic (MCSEM) data shows that both frequency-domain data and time-domain data have certain limitations when using a horizontal electric dipole as the emission source in shallow water. In order to better use MCSEM for offshore oil and gas exploration, we acquire frequency-domain and time-domain data at the same time based on the idea of the time-frequency electromagnetic (TFEM) method used on land. We achieve 1D joint inversion of time-domain and frequency-domain electromagnetic data with the regularization inversion method. According to our model data tests, for a deep reservoir model with 300 m water depth, inverted frequency-domain data can show reservoir location and resistivity, but additional time-domain data cannot improve resolution; for a deep reservoir model with 100 m water depth, the joint inversion results are better than that of a single domain data set.
【Keywords】 marine controlled-source electromagnetic method; time domain; frequency domain; joint inversion;
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