Methods for wavenumber-domain transform calculation and DEXP-based quantitative interpretation of third-order gradient tensor anomalies of gravitational potential
QIU Feng()
Research Institute of Building Materials and Geomechanics, Jiangxi Academy of Water Science and Engineering, Nanchang 330029, China
Since the current instrumental measurement technology cannot directly measure the third-order gradient tensor of gravitational potential, this study proposed a wavenumber-domain transform calculation method for the third-order gradient tensor of gravitational potential based on the gravity anomaly and gradient tensor data. To verify the correctness of this method, this study computed the third-order gradient tensor anomalies of gravitational potential using a 3D model and compared the wavenumber-domain transform calculation results with the forward modeling results, suggesting that the wavenumber-domain transform calculation method is feasible. Moreover, the wavenumber-domain transform calculation results based on gravitational gradient tensor data were more accurate than those based on gravity anomaly data, yielding a root mean square error not exceeding 1 pMKS. In addition, based on the measured data of the Vinton salt dome area, the third-order gradient tensor data of gravitational potential of this area were obtained using the wavenumber-domain transform calculation method. The obtained data were used for DEXP-based data interpretation, attaining consistent depth and boundary results with the previous research results.
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