Optimizing the construction parameters of modified zipper fracs in multiple horizontal wells

Abstract

Abstract In recent years, with the intensive study of volume fracturing, multiple horizontal well fracturing technologies have been widely used in unconventional low-permeability reservoirs to improve production efficiency. Induced stress is the fundamental mechanism that generates a fracture network. In research on the stress disturbance between multiple fractures in continuous construction, changing stress in different fracturing stages have been overlooked; therefore, the mechanism of induced stress changes is not clear in modified zipper fracturing. In this paper, based on the deformation and failure mechanisms of rock, a BEM calculation model considering the induced stress of complex fracture networks is presented. The distribution rule of induced stress in different fracturing stages during the modified zipper fracturing process is studied for the first time in this paper. The simulated results demonstrated that the induced stress is affected by the fracturing stages. In addition, the magnitude and direction of induced stress are constantly changing with the progress of hydraulic fracturing. Based on the formation characteristics of self-supporting fractures under changing stress condition, a new evaluation method for evaluating the area of the stimulated reservoirs under different fracture spacings has been proposed. This work is helpful for obtaining a better understanding of the formation of complex modified zipper fracs and optimizing the fracturing parameters.