oa Geomechanics Predicts the Characteristics of Overpressured Basins

Sharp pressure transition zones, and alterations of stresses within overpressure compartments, are features that are predictable and expected consequences arising from the geomechanical behaviours of typical mud-rich successions. A qualitative analysis based on poro-plastic material responses explains how seals form, how they fail, and how the stress state evolves within compartments. The analysis predicts that rocks within overpressure compartments may be very weak due to dilational deformations. These conditions pose major challenges to drilling and production operations.