Experimental Simulation of Geohazard Evolution During Thermal Recovery of Natural Gas Hydrates Using Electrical Resistivity Monitoring

ABSTRACT The stable occurrence of natural gas hydrates depends on specific temperature and pressure conditions. Disturbances to these conditions readily trigger extensive hydrate decomposition, potentially inducing reservoir instability and engineering geological hazards such as landslides. To elucidate the dynamic patterns of reservoir phase transitions and the evolution of engineering geological risks during heat stimulation of natural gas hydrate extraction, this paper conducted targeted research through indoor physical model experiments. A water tank and sandy soil mixture simulate the seabed sedimentary environment, with high‐resistivity ice blocks substituting for hydrates. A high‐density electrical resistivity metre records dynamic resistivity data during ice melting, simulating reservoir phase transitions and spatial responses during heat stimulation of hydrate extraction. Results show that the initial hydrate‐bearing zone exhibited a resistivity 67% higher than the background, confirming effective identification of hydrate. During decomposition, resistivity decreased significantly, eventually dropping 21% below the background, demonstrating full‐cycle tracking potential. Additionally, the low‐resistivity weak layer expanded to 256 cm 2 , indicating significant soil settlement and pore development that pose structural instability risks. This study provides experimental reference for reservoir dynamic monitoring and disaster risk prevention during heat stimulation of hydrate extraction.