Abstract:
This paper is the result of oil and gas exploration engineering.
Objective The concentrated production area of Huanxiling Oilfield has experienced severe surface subsidence due to long-term hydrocarbon extraction, posing threats to petroleum production facilities and ground infrastructure. Concurrently, recent utilization of near-depleted oil and gas reservoirs in Liaohe Oilfield to construct underground gas storage facilities has introduced additional complexity to surface deformation patterns. The seasonal gas injection/withdrawal cycles during peak-shaving operations induce reservoir pressure fluctuations that compound deformation mechanisms.
Methods This study utilized ascending and descending orbit data from the Sentinel-1 satellite and processed them using the coherence-based SBAS-InSAR technique to obtain LOS deformation for the Huanxiling Oilfield. By combining the two-dimensional surface deformation decomposition method, the vertical and east-west deformation time series results of the study area were obtained. Through fitting the vertical deformation time series results, a seasonal deformation model was constructed, and the seasonal deformation of the study area caused by the injection and withdrawal activities of the nearby gas storage reservoir was analyzed.
Results Results demonstrate a maximum subsidence rate of 88.7 mm/year in the intensive extraction zone, with surface deformation exhibiting both persistent subsidence trends and superimposed annual cyclic "subsidence-rebound" oscillations.
Conclusions These findings provide critical insights into deformation evolution mechanisms for optimizing hydrocarbon production and underground gas storage management strategies.A thorough analysis of the deformation dynamic evolution mechanisms of the Huanxiling Oilfield can comprehensively understand its patterns of change, help predict future deformation, and enable real-time monitoring of reservoir conditions, providing a scientific basis for geological risk assessment and resource development.