Advanced Geomechanics Fracture & Reservoir Application Consortium (AGFRAC)
Dr. Kan Wu
Software 1: A tool package for cross-well strain data interpretation during fracturing
Product use: Identify frac hits and calculate fracture width and height for fracture geometry characterization, cluster efficiency evaluation, leakage analysis, etc., by interpreting cross-well distributed fiber optic strain data.
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The tool package can be directly used in the field to interpret cross-well Low-frequency Distributed Acoustic sensing (LF DAS) data and monitor hydraulic fracture propagation. Raw data from the field measurement can be automatically processed. A novel Green’s function-based inversion model was developed to qualify fracture width and height based on the determined fracture hits. The strain field integrated from strain rates measured by LF DAS along the offset monitor well is related to the fracture widths through a geomechanics Green's function. The least square method was used to solve the linear system of equations.
Software 2: A geomechanics simulator for strain/strain rate waterfall plot calculation
Product use: Calculate strain rate waterfall plots to improve understanding of strain responses and provide guidelines for fiber deployment
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This simulator can be used to generate waterfall plots of displacement, strain, and strain rate observed in both vertical and horizontal monitoring wells. The simulator can simulate various field scenarios, such as single/multiple fractures, intercepting fractures, approaching/by-passing fractures, etc. The Three-dimensional displacement discontinuity method was used to calculate waterfall plots based on evolution of fracture geometry and information of monitoring wells.
Software 3: A complex hydraulic fracture propagation simulator
Product use: Simulate complex fracture propagation in highly fractured reservoirs for multiple stages in multiple wells
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The model couples rock deformation and fluid flow in the fractures and horizontal wellbore. The model incorporates key physical mechanisms of multiple fracture propagation, such as stress shadow effects (interstage, intrastage, between wells), dynamic fluid rate distribution among clusters, the interaction of hydraulic and natural fractures, the impact of bedding layers on fracture height growth, and fluid leaks into natural fractures.
Software 4: A high-fidelity 3D hydraulic fracture propagation simulator
Product use: Simulate a 3D single fracture propagation and benchmark simplified models
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The model fully coupled 2D fluid flow and 3D rock deformation to simulate fracture propagation in heterogeneous reservoirs. The stress difference in multiple layers can be considered and fracture height can be accurately simulated. This high-fidelity simulator can be used as a benchmark model for any simplified simulator.
Product use: Fast calculation of fracture height considering the impact of bedding planes based on the equilibrium height theory
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This simulator can be used to quickly predict fracture height based on given reservoir layer information. The impact of landing depth on fracture height growth can be quickly investigated. The deliverable is the map of fracture height with net pressure. In laminated shale formations, it also predicts the static bedding plane shear slip length. The formation rock properties are handled by the equilibrium fracture height model. The shear slippage of the weak bedding layers is simulated by a joint-element based efficient 2D higher order displacement discontinuity method. The results can be used not only for fracture height design and analysis in unconventional formations, but also as part of the input for a pseudo 3D fracture propagation simulator.