Abstract:

According to the coupling effect between tectonic stress and fluid pressure under high-pressure injection , mathematical model simulating strata deformation was put forward. The numerical simulation of southern Saertu area in Daqing Oilfield indicated that the bigger the injection pressure varied in some areas, the larger the strain magnitude of the standardized bed would be. Likewise, the strain magnitude was smaller in areas with smaller injection pressure variations. The simulation results also indicated that the injected water under injection of water at high pressure could disturb the in-situ stress field fiercely, drive the formation slide from north to south, cause regional concentration of abnormal in-situ stress. The shear stress strength could increase one or two orders of magnitude. and will undoubtedly cause regional or large area casing damages.

Key words: high-pressure injection, stratum strain, numerical simulation, southern Saertu area of Daqing Oilfield