Development and application of drilling fluid in controlling formation damage of Jilin oil field

The rate sensitivity, water sensitivity, salt sensitivity and alkali sensitivity of Jilin oil field formation are quantitatively evaluated and the potential causes to formation damage are found out. A temporary plugging drilling fluid is developed. This drilling fluid is tested in laboratory and applied to production. The evaluation results show that the rate sensitivity is weak, the water sensitivity is medium, salt sensitivity varies from area to area, the critical salinity ranges from one sixteenth to half of formation water, the alkali sensitivity is weakly medium. During drilling operation, the measures to control formation damage should be controlling the salinity and pH value of drilling fluid. Meanwhile, the invasion of drilling fluid filtrate should be controlled, too. The drilling fluid has a high permeability recovery value and can reduce the formation damage during drilling, which will benefit the discovering of oil reservior and controlling formation damage.