Most oil and gas reservoirs experience only small amounts of compaction and surface subsidence. Significant subsidence due to production of hydrocarbons has been observed over some oil and gas fields. This paper presents a review of the fundamentals of reservoir compaction and surface subsidence over oil and gas fields and explains why large-scale subsidence is rare. A new method of estimating maximum potential subsidence is presented and used to analyze the subsidence over oil and gas fields in Louisiana. Large-scale compaction and subsidence are evidently associated with inelastic behavior of the reservoir rock and in some cases of the surrounding rock. No reliable methods have been established for predicting either the transition from elastic to inelastic reservoir rock behavior or large-scale reservoir compaction and subsidence.

The preconsolidation effect evident in some field data introduces an additional difficulty in understanding and predicting subsidence. Various possible causes for the effect include uplift and erosion, temporary pressure drop or an increase in horizontal stresses prior to hydrocarbon production, effects of loading rate on reservoir rock, and changes from elastic to inelastic behavior of the reservoir rock or surrounding formations.