Qualitative modeling of multi-stage fractured horizontal well productivity in shale gas reservoir

Abstract

As an important unconventional gas resource, shale gas has become an important part of gas production in recent years with the advantage of horizontal well drilling and large-scale multistage hydraulic fracturing completion technologies. The shale gas reservoir numerical simulation advances were reviewed and a multi-stage fractured horizontal well numerical simulation was performed to qualitatively modeling the well productivity in over-pressured shale gas reservoir based on actual shale properties and well completion parameters. A single horizontal well model was established on the basis of dual-porosity model and logarithmically spaced grid refinement. A comprehensive comparison and analysis of the initial average gas production, daily gas production, cumulative gas production, adsorbed gas and free gas cumulative production were provided to investigate the influence of matrix permeability, SRV permeability, hydraulic fracture conductivity and half length, SRV size, bottomhole pressure on the well performance. The research shows that for the high matrix permeability (K m > 10 À7 mD) and low SRV permeability (K SRV < 0.01 mD), the SRV permeability has a significant impact on the initial average gas production. For the high matrix permeability (K m > 10 À7 mD) and medium SRV permeability (0.01 mD < K SRV < 0.5 mD), the initial average gas production is controlled by both the matrix and SRV permeability. For the high matrix permeability (K m > 10 À7 mD) and high SRV permeability (K SRV > 0.5 mD), the initial average gas production is mainly controlled by the matrix permeability. When the matrix permeability is lower than 10 À9 mD, the cumulative gas production is too low to be of economic interest. For the matrix permeability (10 À9 mD < K m < 10 À5 mD), the matrix permeability and SRV permeability are all important factors that influence the cumulative gas production. For the matrix permeability (K m > 10 À5 mD), the matrix permeability has much more impact on

Mechanisms of Hydraulic Fracture Propagation and Multi-well Effect during Multiple Vertical Well Fracturing in Layered Reservoirs with Low Permeability

“…Nevertheless, most existing large-scale fracturing models assume that the mechanical properties of the reservoir rocks are homogeneous. This assumption helps simplify the problem and realize large-scale fracturing simulation. − However, this assumption ignores the effect of the stratum property difference on the fracture propagation. It is well-known that the stratum property difference significantly affects the behavior of hydraulic fracture propagation in low-permeability reservoirs, such as the fracture propagation range, breakdown pressure, and interaction between wells. , Therefore, the establishment of a large-scale layered model, which can accurately characterize stratum properties, is of great importance for the study of hydraulic fracture propagation mechanisms in low-permeability reservoirs.…”

Integrated Workflow of Geomechanics, Hydraulic Fracturing, and Reservoir Simulation for Production Estimation of a Shale Gas Reservoir

“…Yu et al [2] performed a multistage fractured horizontal well numerical simulation on the basis of reservoir properties and completion parameters from an actual horizontal exploration well in China. They analyzed the effect on multistage fractured horizontal well's performances for matrix permeability, permeability of stimulated reservoir volume (SRV), HF conductivity and half-length, SRV size, and bottomhole pressure.…”

Supplementary energy development boundaries of staged fracturing horizontal wells in tight oil reservoirs

“…In the early 1960s, the small well spacing pilot tests were carried out in Daqing Oilfield, China, and four-point well pattern was adopted in the test area with the well spacing of 750 m. Compared with the water injection results of the control well group under the same conditions, the recovery rate was increased by about 10%. CO 2 -flooding tests were carried out under different gas injection pressures (Liu and Chen, 2010; Wang et al., 2014; Wang and Gu, 2012; Yuan et al., 2005). The rule of the impact of gas injection pressure on CO 2 -flooding gas channeling was studied.…”

“…However, tight reservoirs are usually characterized by small pore throats, low permeability, large seepage resistance, and low single well production, and the effective development rates of the tight oil reservoirs are low (Lin et al, 2018(Lin et al, , 2019Shanley and Cluff, 2015;Wang et al, 2018). In order to improve the development efficiency, the staged fracturing horizontal well technology emerged Jamiolahmady, 2018a, 2018b;Shen et al, 2018;Yu et al, 2017). The United States, Canada, and many other countries have initiated gas displacement production in their oilfields.…”