Effect of hysteresis on petrophysical properties of limestone hydrocarbon reservoir rock

摘要: Abstract The petrophysical properties of carbonate reservoirs may change when they are subjected to mechanical loadings due the softness formation. As reservoir fluid pressure declines production, net load on rock increases, which leads compaction and decrease in its pore volume, causing blocking throats permeability reduction. In this study, we experimentally investigated hysteresis effect two core samples during loading using CMS-300 apparatus. structure was processed by CT scan images analysis size distribution also conducted mercury injection testing followed scanning electron microcopy (SEM). Our results indicate that isotropic long-term short-term considerably grain structure, while do not have a clear effect. porosity induced cyclic affected intergranular micro-extension fractures. greatest reduction fractured limestone occurred at first step; however, further strongly consolidation adherence matrix. This fluctuating trend observed for permeability, with severe crushed grains were placed connected path. measured carbonated rocks, as stress-sensitive parameters, along micro-fracture effects unloading, can be considered production management reservoirs. They useful predicting any possible risks different periods life determining optimum reservoir.