The Formation Mechanism of Abnormal Overpressure in Depositional Basins and Its Controlling Effect on Hydrocarbon Accumulation

Abstract

Abnormal overpressure is commonly encountered in depositional basins and is considered a key factor influencing the efficiency, safety, and assessment of hydrocarbon accumulation dynamics in drilling projects. Research indicates the following: (1)The genesis of abnormal overpressure in depositional basins can be broadly classified into five types, including disequilibrium compaction, fluid expansion, diagenesis, tectonic squeezing, and pressure transmission;(2) For specific geological conditions in depositional basins, the mudstone logging curve chart method is employed to assess abnormal overpressure;(3) The impact of abnormal overpressure in depositional basins on hydrocarbon accumulation is manifested in four aspects: its influence on hydrocarbon generation from source rocks, its effect on reservoir connectivity, its impact on seal integrity of cap rocks, and its influence on hydrocarbon migration. These research findings provide crucial guidance for a deeper understanding of abnormal overpressure in depositional basins and its significance in the evaluation of hydrocarbon exploration.