Research On Productivity Prediction Forvolume Fractured Horizontal Well Of Tight Reservoir In Q Oilfield

With the deep-going progress of petroleum exploration and development, people are constantly stepping into the actual development of more compact reservoirs. Currently the shale gas, shale oil and tight oil at extra-low porosity and permeability gradually become the focus of hot spots. America has achieved energy self-sufficiency by the revolution of tight oil and gas, the total output even leaves behind Saudi Arabia’s. The tight reservoirs at low permeability have huge reserves in the world. The reasonable and effective development of such reservoirs have great significance.But tight reservoirs have compact lithology, poor permeability and porosity, greatly developed of micro-fractures, extremely intricate micro-structure. The fluid flow in it doesn’t comply with Darcy’s law and the reservoir has strong stress sensitivity. Usually fractured horizontal well technology is used to explore this petroleum reservoir. Bus a general multi-stage fracturing doesn’t satisfy the effective development and volume fracturing is needed. The volume fracturing transforms reservoir integrally by forming branched fractures from primary or connecting nature cracks and finally take the shape of complex fracture network. But this brings many difficulties to forecast yield accurately. It’s a challenge to correctly describe and model the intricate fracture network in volume fracturing. Meanwhile the output forecast of fractured horizontal well is also a difficult point in fractured horizontal well development technology. Thus, It is of great significant to forecast fractured horizontal well output by considering the characteristics of tight reservoir and complex fracture network in fractured horizontal well technologyIn this paper we carried out research on the production prediction method of horizontal well developed and volume fractured tight sandstone reservoir in Q oilfield. We studied the starting pressure gradient and stress sensitivity of natural cores from tight sandstone reservoir in Q oilfield by experiment, and got the corresponding change law with fitting method. We also made a fracture model of volume fractured crack network by double medium flow model and a productivity model of volume fractured horizontal well by numerical method. Finally we programed a corresponding production prediction software. By the software we studied the output change laws of volume fractured horizontal well in different geology and production conditions. Through the practical application in production prediction of horizontal well developed and volume fractured tight sandstone reservoir in Q oilfield, We got a satisfactory result.