ABSTRACT
This chapter is concerned with the numerical simulation of compaction of hydrocarbon-bearing rocks, more commonly referred to as reservoir rock. With respect to operations in the petroleum industry, rock compaction may be defined as the reduction in overall volume of a subsurface stratum of rock as a result of production of fluids (oil, water and gas) stored within the pore space of the reservoir rocks. During production, both the volume of fluid and the fluid pressure decrease. The weight of the Earth's crust above the reservoir provides a near-constant state of vertical compressive stress on the reservoir, which results in vertical compressive strain within the reservoir rock as pore pressure is reduced during production. While rock compaction can be an important factor to be considered in reservoir engineering and analysis in gravity drained reservoirs, large amounts of compaction can lead to significant subsidence at the surface above the reservoir and can lead to damage and failure of wells in and around the reservoir. Reservoir compaction in the petroleum industry has been responsible for large financial losses to the operators of oil or gas fields due to well repairs and failures, and even costly damage to offshore platforms. Therefore, the numerical simulation of compaction has played an important role in the development of many fields and in the continued development of fields with compaction-sensitive rocks.
