Investigation on Fiber Assisted Multistage Fracturing of Horizontal Well in Tight Low Permeability Sandstone Reservoirs

Abstract

Tight sandstone reservoirs, widely distributed in the world, are the important oil and gas exploration and exploitation area in the future and have a favorable development prospect. Multistage fracturing of horizontal well is a necessary technology to inspiring the production potential and enable commercial productivity for tight reservoirs. Due to the multiple functions, degradable fiber is widely applied during hydraulic fracturing. On the one hand, fiber can enhance the sand patch profile when it was injected into the fracture with the carrier fluid; On the other hand, fiber aggregation can accelerate the formation of temporary plugging agent, which is conducive to the uniform propagation of fractures. In this paper, we conducted a series of experiments to evaluate the properties of fiber in detail. Moreover, the pilot application of fiber which was injected during the whole hydraulic fracturing was also carried out. The laboratory evaluation experiments mainly achieved the following findings: 1. The length, diameter and density of fibers are approximately 6mm, 10μm and 1.24 g/cm3, respectively. 2. The fiber can be well dispersed in high viscosity slick water with almost no settlement. 3. Under high closure pressure, the conductivity of fiber and proppant mixture is higher than that of pure proppant. Furthermore, the field case shows that the fiber assisted fracturing makes the permeability-challenged formations economically recoverable, which deepens the understanding the effect of fibers and provides fundamental for field treatment design.