Joint inversion of geophysical data under the guidance of petrophysical properties

The joint processing and integrated interpretation of multi-source geophysical exploration data are indispensable to the exploration evaluation of deep geothermal resources. Joint inversion and post-inversion geological differentiation are two major hot research topics in deep resource exploration. To integrate the multi-source geophysical field information and reduce the inversion multiplicity of single geophysical fields, this study built a structural model using the stratigraphic structure information from seismic interpretation, with the prior information of petrophysical properties as a guide. This study constrained the stratigraphic geophysical parameters using the Gaussian mixture model and conducted regularized joint inversion of gravity, magnetic, and magnetotelluric data, thus achieving the coupling of multiple physical structures. Finally, this study developed the software for the joint inversion of gravity, magnetic, magnetotelluric, and seismic data. Based on the joint inversion results and electrical resistivity, this study predicted the temperature field at typical hot dry rock sites using the Arrhenius law. The forward modeling results of the theoretical model for cubic anomalies were used for the joint inversion. Compared with individual inversion, the joint inversion performs well in the spatial characterization of anomalies and the recovery of physical property values. Furthermore, the joint inversion can fully integrate multiple data on geology, petrophysical properties, and geophysics, thus well conforming to the actual conditions.