We introduce a formalism, Deformation Analysis in Reservoir Space (DARS), to quantitatively predict the degree of compaction and potential for induced faulting in a depleting reservoir. Compaction occurs when the stress state exceeds the end cap (or critical state) of a formation at any given porosity. For reservoirs in which the vertical stress is larger than the two horizontal stresses, there is also a potential to induce normal faulting in a depleting reservoir when the change of minimum horizontal stress, ΔSh, exceeds a critical fraction of ΔPp (the change in formation pressure due to depletion). The stress path defines the change in horizontal stress with depletion (A=ΔSh/ΔPp). Utilizing relatively simple laboratory experiments, we transform the end caps from laboratory space into reservoir space (DARS) such that production data can be evaluated directly to study the evolution of the deforming reservoir due to production. Field X in the Gulf of Mexico is examined in the context of the DARS analysis. The analysis shows that the initial state of the reservoir was such that normal faults present in the field were active. However, production-induced normal faulting is not likely to occur. Deformation is dominated by compaction. Our analysis estimates that porosity of the formation was reduced from about 23% to 21%, while the permeability was reduced from about 230md to 50-140md.

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