ABSTRACT
Here physical experiments were designed to analyze the reason for the low oil flowing capacity through matrix due to fracture plane damage in the process of stimulation at low permeability reservoir. The mixed oil by a neutral white oil and a crude oil from D oilfield has a viscosity of 9.85 mPa ⋅ S under 60°C while the formation water is the standard saline water of KCl type for clay antiswelling purpose. The fracturing fluid is mixed by a hydroxypropyl guanidine gum of 1% and a sodium borate of 0.05%. After enough agitation, sodium carbonate or sodium bicarbonate can be used to change the PH value of the fracturing fluid in 6-11. The 4 fracturing fluids A1, A2, S3 and S4 are developed by an Oilfield Institute for evaluation. A1 and A2 are mixtures while S3 and S4 are composed liquids.
