Earthquakes can drive hydrocarbon seepage along the Cyprus Arc

Abstract Understanding the mechanisms controlling hydrocarbon seepage in marine environments is crucial due to the toxicity of liquid components and the contribution of the gaseous fraction to carbon budgets. While natural seepage is common, the role of earthquakes remains poorly understood. Here, we show that major earthquakes along the East Anatolian Fault in 2023 triggered hydrocarbon expulsion hundreds of kilometers away. Satellite monitoring revealed that nine days after the 7.8 moment magnitude mainshock, oil seepage began at a new site, leading to a 71% increase in the emitted oil volume over six months. Four events had energy densities and dynamic strains similar to known cases of earthquake-triggered hydrological responses. Our results suggest that low-frequency waves and high dynamic strains likely extended pathways and mobilized fluids in three-phase systems (oil, gas, water). Earthquake-driven hydrocarbon seepage should be monitored near active seismic zones to better account for greenhouse gas emissions in carbon budgets.