Petrophysical substantiation of geological section elastic-velocity property recovery potential based on TEM data

The geological section of Eastern and Western Siberia (Russia) is a very complicated object for seismic exploration. The research presented in the article is aimed at studying a petrophysical relation between electrical resistivity and P-wave velocity, as a basis for predicting the velocity model of the upper part of the section based on TEM sounding. Having performed a numerical modeling of petrophysical function, the authors calculated the dependency curves of electrical resistivity on the P-wave velocity. The obtained results of mathematical modeling and field experiments have proved the effectiveness of the proposed methodology as it increases the accuracy of geological model construction and enhances prediction reliability. Based on the dependences obtained, conclusions were drawn about the geological conditions favorable for a steady transition of section geoelectric characteristics to the velocity ones. The proposed technology is shown to provide a reliable reconstruction of the velocity model of the upper part of the section. The use of the developed methodology allows to improve the quality of seismic data processing and increase the accuracy of geological section boundary mapping at minimum cost based on the nature of the problem under investigation.

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