Investigation of sensitivity of surface deformation to subsurface properties and reservoir operations

Abstract

An experimental study is performed to understand the sensitivity of ground deformation to subsurface properties and operations of oil and gas fields. Ground deformation, or more severely subsidence, may pose concerns for human settlements situated above the reservoir. This Masters thesis will study a realistic sample problem on its surface deformation sensitivity, in hopes of providing a sound basis for future characterization of subsurface properties and the forecast of surface deformation due to oil and gas production. Iteratively coupled simulations are performed to test how sensitive the surface deformation is to changing subsurface parameters. To test the validity of such coupled simulator, comparison of the displacement results with those of another commercially available software is also carried out. Results show that the change of surface displacement particularly in the vertical direction tends to be within the range of detection of satellites, of which data will serve as the input of future inversions with the Ensemble Kalman Filter (EnKF).