Mathematical modelling of gravitational compaction and clay dehydration in thick sediment layers

A R Y Gravitational compaction is an important process in sedimentary basins which controls the reduction of porosity with burial depth and the development of high pore fluid pressures. Often, sediments contain hydrated, expandable clay (smectite) that can undergo a transition to a dehydrated, non-expandable clay (illite). During dehydration, structural water bound within the sheet layers of smectite is released into the pore space, which can increase the pore pressure and influence geological processes such as solute transport, hydrocarbon migration and hydrothermal fracturing.