Study on Reservoir Geological Characteristics and Potential Damage Mechanism of FIOC Oilfield in Sargiz

With the in-depth development of the Sargiz oilfield in Kazakhstan, oil layer protection plays an extremely important role in the development process. The petrological characteristics and pore types of the reservoir were analyzed by X-ray diffraction and electron microscopy. The average face ratio of the reservoir was 19.30%. The main pore type was intergranular pore and the face rate was 17.52%. The total amount of clay minerals in the reservoir core is 7% - 10%, and the clay minerals are mainly illite, Yimeng, kaolinite and chlorite; the shale content of the main oil-bearing layer is about 3% - 10%. Refer to relevant industry standards for speed, water, stress, acid, and alkali sensitivity experiments to study the potential damage mechanism of the reservoir. According to the above experiments, the oilfield reservoirs have no speed-sensitive damage and are weakly water-sensitive reservoirs; the reservoirs are highly stress-sensitive and easy to produce sand when the stress changes; they have moderately weak acid sensitivity and weak-medium weak alkaline.