The Effect of Chemical Compaction on Fluid Overpressure Development and Seal Integrity

O-31 THE EFFECT OF CHEMICAL COMPACTION ON FLUID OVERPRESSURE DEVELOPMENT AND SEAL INTEGRITY H.M. HELSET J.C. MATTHEWS and P.H.M. REEMST Summary We demonstrate the importance of chemical compaction on porosity loss rates and overpressure development in case studies from the Gulf of Mexico and from the mid-Norway Halten Terrace. Porosity loss rates due to chemical compaction may exceed porosity loss rates corresponding to mechanical compaction at deep burial. Depending on the basin setting more than 50% of the present day overpressure can be attributed to chemical compaction processes. Our model of fluid overpressure incorporates chemical compaction of sediments including quartz