Characteristics And Sensitivity Evaluation Of Tight Sandstone Reservoirs

Tight sands formation is more vulnerable to the impact of acid fluid and other foreign contamination with the obvious characteristics of low porosity and low permeability.For the distribution and development of tight sands in our country,petrographic analysis has been done in the formation of the target area and core physical properties tests have been done in the specific well.Based on the analysis of the lithology,the wettability,the seepage and the electrical relation of the core,the potential sensitivity was predicted.In the core physical properties tests,the nuclear magnetic resonance was used to measure the more accurate porosity.The sensitivity evaluation experiment selected a representative of the 20 core s.Based on the improvement of experimental time and device in the conventional method,including the conventional physical properties analysis and flow experiment of the core,the degree and mechanism of the acid sensitivity of the tight sandstone reservoir were studied with the twenty typical flow results.The sensitivity and intensity of the target single well core scale is water sensitive,alkali sensitive,rapid sensitivity,salt sensitivity,acid sensitivity,which is consistent with the theoretical analysis.This method can be applied to measure the sensitivity of tight sandstone reservoirs in western and a good application effect has been achieved.This research could provide important reference for reservoir evaluation and logging interpretation to improve the enhanced oil recovery.The suggestions are that the related measures should be optimized on regular and the residual fluid should be discharged in time.