Integrated Modeling of Multi-Stage Hydraulic Fracturing of Low-Permeable Reservoirs

Abstract

The most effective method for developing lowpermeability reservoirs is multi-stage hydraulic fracturing (MSHF), which is confirmed by its intensive development in Russia. A feature of modeling hydraulic fracturing of low-permeability reservoirs is not only the need to calculate the optimal parameters of multi-stage hydraulic fractures and their relative positions, but also taking into account the influence of hydraulic fracturing on changes in the filtration properties of the formation. To create an optimal multi-stage hydraulic fracturing model, it is necessary to improve existing techniques and optimize them using 3D modeling, which in turn requires the use of extended well and laboratory research methods. As a result of the research performed, a new method for optimizing multi-stage hydraulic fracturing was created using input data from constructed petrophysical, lithologicalgeochemical, geomechanical, geological and hydrodynamic models. Direct interconnection of the input models and their inverse relationship with the results of calibration of the hydraulic fracturing model based on the analysis of hydraulic fracturing parameters and well operation reduce the influence of the subjective factor on the modeling and build more correct models of multi-stage hydraulic fracturing. It is shown that the integrated modeling allows to create optimal multi-stage hydraulic fracturing models, and also to determine a set of additional studies necessary to clarify the data for correct design of the models. The proposed approach was tested in several fields with completely different geological and geophysical characteristics of the formations. For the first time in Russia MZHF technology for low-temperature gas formations using hydrocarbon-based fluid and high-speed hybrid MSHF of high-temperature oil formations were developed and performed. This became the basis for the development of low-permeability Turonian, Jurassic, Achimov reservoirs and unconventional deposits of the Bazhenov formation.