Research on Site Selection and Evaluation of Available Conditions for Salt Cavern Gas Storage in the Dawenkou Basin

Large-scale energy storage has become critical for the integration of renewable energy. Compressed air energy storage (CAES) imposes urgent demands on the precise evaluation and efficient exploitation of high-quality salt cavern resources. The Dawenkou Basin is a typical continental layered rock salt distribution area in North China, and the assessment of its salt cavern energy storage potential is vital for regional energy storage layout planning. Taking the continental layered salt deposits in the Dawenkou Basin as the research target, this study integrates 3D seismic surveys, borehole data interpretation, and machine learning algorithms to establish a 10-indicator evaluation system tailored to the energy storage potential of continental layered rock salt. By adopting a coupled weighting method that combines random forest and the analytic hierarchy process, three primary controlling factors are identified: the number of salt layers, thickness of salt layers and depth of salt layers. Quantitative zoning of energy storage potential and optimal zone selection are completed at the basin scale. The results reveal that the high-potential zone for salt cavern energy storage in the Dawenkou Basin covers an area of 12.8 km2 and is capable of generating 11,542~14,333 × 104 m3 of salt cavern volume; the medium-potential zone spans 15.87 km2, with a feasible salt cavern volume of 5773~7169 × 104 m3; and the low-potential zone occupies 25.15 km2, corresponding to a salt cavern volume of 7764~9642 × 104 m3. The evaluation method for the energy storage potential of continental layered rock salt developed in this research fills the gap in evaluation frameworks for thin interbedded rock salt and provides a standardized technical paradigm for the exploitation of salt cavern energy storage resources in analogous salt basins across North China. The evaluation findings can offer scientific support for regional novel energy storage industrial planning and engineering site selection.