New Methods for Controlled Reserves Analysis in tight oil reservoirs

This paper describes the physical model of a multi-stage fractured horizontal well in tight reservoirs. Moreover, a composite zonal productivity prediction model of staged multi-cluster fracturing horizontal well was established. The inner area of the model is a dual porosity model composed of matrix and micro-fracture network formed by the artificial fracture and natural fractures opened by fracturing treatment, and the outer region is a single matrix. The effects of threshold pressure gradient, stress-sensitive matrix permeability, capillary pressure, and the conductivity failure capacity of artificial fractures in the production forecast are fully considered in the model. The influence of different clusters, different fracturing stages, half-length of fractures, and permeability of the micro-fractures on the oil drainage area of the horizontal well was analyzed via numerical simulation. The influencing factors of different well patterns and drainage area of multi-stage fractured horizontal well were also studied. The method of using drainage radius of multi-stage fractured horizontal well and the technical countermeasures to improve the well productivity are instructive for the development of tight oil reservoirs.