In this paper, according to the method of electrical constraint inversion, we can improve the accuracy of inversion interpretation using the constraint of electrical logging data in the inversion process, which is conducive to obtain more abundant geoelectric information. On the basis of the conventional OCCAM inversion algorithm, the model roughness in the objective function is improved, and the formula of the electrical constraint inversion iterative algorithm is derived in detail based on the modified objective function. Taking the geothermal exploration in Changbai Mountain area as an example, the measured CSAMT data are used as the resistivity model for inversion, and the electrical property is constrained by the actual data from wells drilled in the section. It can be found that the method of electrical constraint inversion can improve the accuracy of inversion interpretation and guide the development of constrained inversion methods in different ways.
Key words
CSAMT /
constrained inversion /
OCCAM /
logging data /
inversion accuracy
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Funding
Supported by projects of the National Natural Science Foundation of China (Nos. 41072038, 90814003) and China Geological Survey (Nos. 1212010070301, 1212321013019).
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