Print this pageAAPG ANNUAL CONFERENCE AND EXHIBITION
Making the Next Giant Leap in Geosciences
April 10-13, 2011, Houston, Texas, USA
An Integrated Geomechanical Approach for Development of the Mars Field in the Gulf of Mexico
(1) Shell Oil Company, New Orleans, LA.
A robust geomechanical model can provide valuable insight into risks associated with near-field exploration, in-field development, and surveillance programs. Throughout the exploration and production history in the Mars field (Mississippi Canyon 807), Shell has continuously updated, enhanced, and calibrated their basin scale 3D geomechanical model. The model has been used extensively at various stages of the Mars development for reservoir management, drilling and completion design, wellbore stability, water flooding, 4D seismic, compaction, and subsidence studies.
With an ongoing drilling and surveillance program, the geomechanical model has been calibrated with new wireline log data, core measurements, surface subsidence measurements, reservoir pressures, and formation compaction data. These updates allowed us to identify potential drilling hazards and high risk zones when drilling near salt or through depleted sands. The model was used to identify a potentially hazardous shear zone near a severely depleted sand and salt nose resulting in choosing a different location for a replacement injector well. We have also utilized the geomechanical model to identify shallow shear zones associated with a series of depleted sands as a site screening tool for a second Mars platform. In addition, by incorporating our dynamic reservoir models into our geomechanical model, we are able to accurately predict the magnitude of future reservoir depletion and the effect on wellbore stability for current and future wells.
As our knowledge of rock properties, stresses, and pressure distribution continued to improve, a series of smaller models focusing on deeper subsalt prospects within the Mars basin were created as extensions to the main Mars model. These models have been successfully integrated and influence field development plans for two new discoveries at a very early stage.