One-dimensional accurate calculation of transient electromagnetic responses based on B-spline interpolation
XING Tao1(), WANG Yao2, LI Jian-Hui2,3()
1. Beijing Tanchuang Resources Technology Co., Ltd., Beijing 100071, China 2. School of Geophysics and Geomatics, China University of Geosciences (Wuhan), Wuhan 430074, China 3. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Wuhan), Wuhan 430074, China
In the one-dimensional (1D) forward modeling of transient electromagnetic (TEM) responses based on spectral methods, multiple calculation steps significantly influence the calculation accuracy of TEM responses. To improve the efficiency of 1D forward modeling, the common practice is to directly calculate the frequency-domain electromagnetic responses of dozens of frequency points and then obtain the responses of hundreds of frequency points through cubic spline interpolation. Although the numerical results calculated using the cubic spline interpolation function can meet the requirements of most forward modeling scenarios, their accuracy can be further improved. This study introduced high-order B-spline interpolation into the 1D forward modeling of TEM responses to replace the conventional cubic spline interpolation and verified the accuracy of the method based on magnetic dipole sources and circle-shaped loop sources. The results show that the TEM responses of several geoelectric models calculated based on high-order B-spline interpolation exhibit higher accuracy than those calculated using conventional cubic spline interpolation.
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XING Tao, WANG Yao, LI Jian-Hui. One-dimensional accurate calculation of transient electromagnetic responses based on B-spline interpolation. Geophysical and Geochemical Exploration, 2023, 47(5): 1316-1325.
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