Experimental Study On Influence Of Saturated Fluid On Acoustic Characteristics Of Shale

At all stages of shale reservoir production,fluid contact with reservoir rock is unavoidable.Based on this,it is of great significance to study the effect of saturated fluid on the physical properties of shale.In this paper,we use shale samples from different regions,apply ultrasonic speed tests,triaxial rock mechanics experiments,acoustic emission,and other experimental means to change the physical properties caused by saturated shale and supercritical CO₂ in reservoirs,influence factors,and laws.,change process and mechanism were studied.Experiments show that the interaction between fluid and shale is much stronger than other types of rock samples.After fluid saturation,the P wave velocity increases,the S wave velocity decreases,the stress sensitivity increases,and dynamic Young's modulus fluctuates.Matsube improved significantly.Clay is the most important factor in the change of physical properties of shale reservoirs during saturation of fluids.The expansion of rock samples correlates well with their Poisson's ratio.The dilatancy of shale is the most important factor for evaluating the strength of shale and water.One of the parameters.In addition,the sensitivity of the strata-developed shale to the fluid saturation effect is much higher than that of the undeveloped rock.The monitoring of water saturation shows this effect.Compared with distilled water,supercritical CO₂ can not only improve the pore permeability,but also has a larger impact range,and can also promote the generation of micro-cracks within the rock.This study reveals the mechanism and laws of changes in shale physical properties during fluid saturation.The proposed ultrasonic monitoring method can detect the range and speed of fluid saturation.Provides monitoring tools for an in-depth understanding of shale saturation mechanisms and processes.