Prediction on Basement Fracture in Jambi Depression, South Sumatra Basin, Indonesia

South Sumatra basin, classified as Cenozoic backarc rift basin, had undergone multistage tectonic activities resulting in complicated basement with varied lithologies. With the comprehensive study involving geophysics, geostress field, and seismic attributes on basement, the criteria for lithology determination and distribution are proposed, and the method for fractured basement prediction was also specified. It is shown, from the wells drilled into basement, the lithological types mainly consist of igneous, carbonate, and metamorphic rocks. Based upon geophysical analysis and well logs calibration with core and seismic data, the well-log response model is built. Furthermore, with the application of waveform classification and gamma ray inversion, the distribution of lithological types in basement is presented. Two-stage tectonic fractures, NE–SW fractures during post-rift stage, NW–SE and NNW–SSE fractures during inversion stage, were predominately developed near major faults and uplift areas from geostress field stimulation. The result of fractured basement prediction, using seismic attributes such as ant tracking, enhanced coherence, curvature, and pre-stack anisotropy, matches well with that using geostress field stimulation. It can be concluded that the prediction method, comprehensively using geostress field stimulation and seismic attributes analysis, is effective and suitable for fractured basement and will contribute to hydrocarbon exploration in basement.