Southern China's igneous province,as a significant geothermal resource area in China,possesses abundant geothermal resources owing to its favorable accumulation conditions for medium-to-high temperature geothermal resources.However,gravity-magnetic-magnetotelluric exploration methods fail to sufficiently characterize the formation structures,geothermal reservoir boundaries,and the spatial distribution of geothermal reservoirs within the concealed fault zones,posing challenges in exploring deep geothermal resources.Hence,this study delved into the key seismic processing techniques for deep geothermal exploration based on 3D seismic exploration data,establishing a targeted processing flow.First,the problem of low signal-to-noise ratios in deep layers was solved through fine-scale preprocessing for deep geothermal reservoirs,laying a solid data foundation.Then,a high-precision velocity model was built via fault-guided tomography velocity modeling.Finally,the high-precision imaging of deep geothermal reservoirs was achieved using the amplitude-preserving low-frequency reverse-time migration technology,thus improving the imaging quality and the characterization accuracy of geothermal reservoir spaces and high-steep boundaries.Field data-based testing verified the validity and practicability of the processing flow.
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