For ultra-low permeability rocks like shale, production of gas or oil is all about the fractures – both induced and naturally occurring. How well you’re able to define and understand the fracture network drives the solutions to key operational decisions such as:
- Where are the optimal locations?
- How should reservoirs be completed?
- How should development be staged and prioritized?
- What is the expected ultimate recovery and its associated uncertainty?
Golder has found that the answers for unconventional gas resources and production benefit from geologically and mechanically realistic 3-D analysis of the interaction of natural and hydraulic fractures during hydrofracturing and production. This is based on our work with nearly three-quarters of the world’s largest oil and gas companies, and most of the world’s major mining companies.
FracMan Sets Standard for 3-D Discrete Fracture Network Simulation
Golder first introduced its FracMan® discrete fracture network modeling software some 30 years ago. Since 1987, our interdisciplinary teams of geologists and engineers have used FracMan for fractured rock masses throughout the world — for nuclear waste repositories, underground and surface mines, tunnels, slopes, dams, environmental projects, conventional carbonate oil and gas reservoirs, and coal bed methane projects.
FracMan provides a geologically realistic, 3-D quantitative description of the spatially varying natural fracture and its hydromechanical properties, and uses this understanding to engineer the safe and economically efficient development of fractured rock masses for civil, mining and oil resources.
Next Generation FracMan Provides Unparalleled Realism for Design of Hydraulic Fracturing Operations
In the past 10 years, Golder has incorporated critical new capabilities for analysis and modeling of hydraulic fractures into FracMan and created the world’s first truly 3-D hydraulic fracture DFN simulator.
The 3-D DFN hydraulic fracture simulator directly assists with achieving optimal well locations, trajectories, completions, and stimulations. This provides our clients with clear value in improved production, lower development costs and improved environmental protection.
Re-Fracturing for Added Cost-Efficient Production
Current oil/gas market economics put the focus squarely on reducing costs. Many companies have turned to Golder to assist them with the re-stimulation of existing wells to provide increased production at a lower cost than the drilling and completion of new wells. Re-stimulation must strategically target remaining reserves, which requires an accurate prediction of the stress re-distribution produced by the initial hydrofracturing, and the associated changes in local rock strength and deformability. FracMan’s DFN geo-mechanics/hydro-dynamics simulator allows us to work with the client’s operations team to create and validate models of the initial phase of hydrofracturing, and then to rapidly explore alternative re-stimulation designs without having to resort to the high-cost practice of carrying out multiple alternative designs in the field.
3-D Fracture Modeling Valuable for Geohazard Risk Analysis
The hydraulic fracture simulations have also proved valuable in geohazard risk assessments, providing an understanding of induced seismicity and mitigation of seismic risks, along with the assessment of potential migration of frac fluids from the reservoir to any overlying aquifers or accessible environment. These types of calculations directly feed into the work of Golder’s environmental and safety teams that perform Environmental and Social Impact Assessments necessary for permitting and licenses.
The Next Challenge
Our international team within Golder’s FracMan Technology Group is currently studying the production rates of unconventional reservoirs and how might the industry avert the significant decrease in production that can occur as early as 12 to 18 months into most unconventional wells’ production cycle. We’re using FracMan’s geomechanic and hydrodynamic modeling features to help uncover answers for sustaining economic rates of production over longer periods of time and minimize social and environmental risk.
Please feel free to contact our team at dersh@golder.com to see how a better understanding of rock fractures can provide value to your unconventional gas operations.
