Fracture  Design,  Placement  And  Sequencing  In  Horizontal   Wells

According to a 2011 EIA report¹, almost all incremental oil and gas production in the lower 48 will come from unconventional resources, including shales, low permeability sands and heavy oil. Virtually all the oil and gas produced from unconventional reservoirs will rely on the application of multiple fractures in horizontal wells.  The development of shale oil and gas plays is largely dependent on the cost of drilling and fracturing horizontal wells. Rapid decline rates require that new wells be drilled just to maintain production. A reduction in the cost and environmental footprint of drilling and fracturing will lead to a significant expansion of shale oil and gas development.

The primary objective of this proposal is to develop a new generation hydraulic fracturing model, based on a peridynamics formulation, that will allow us to model multiple, non-planar, competing fractures in heterogeneous shales and to use this model to design wells and hydraulic fractures that will better drain the reservoir volume thereby reducing drilling and completion costs and improving the economics of shale oil and shale gas production.

Peridynamics is a recently developed theory of continuum mechanics that allows for autonomous fracture propagation and has shown great promise in modeling material failure in many applications. Peridynamics has, however, not been applied to study the problem of hydraulic fracture propagation. The goal of the proposed research is to apply the computational implementation of peridynamics to the problem of hydraulic fracture simulation. In order to accomplish this objective a computational solid mechanics code that utilizes the physical features of the peridynamic theory will be coupled with fluid and porous media flow models to provide two-way fluid-structure interaction in evolving multi-fracture networks.  The open-source, production quality code, called Peridigm, is currently being distributed from Sandia National Laboratories and was developed from the onset using modern, modular, object-oriented programming techniques to scale efficiently from small desktop computers to the world’s largest massively-parallel supercomputers.  The theoretical and computational implementation of new peridynamic material models, robust solvers, and other improvements of a fundamental nature that result from the proposed will be maintained in the code repository for the benefit of all users.  The scope of the proposed will include validating the new models against existing field data from known multi hydraulic fracture treatments. 

At the end of the project, following key deliverables will be made available for use by operators:

• A new generation hydraulic fracturing model that will allow a user to model the propagation of multiple, non-planar hydraulic fractures and create a stimulated rock volume (SRV).
• The ability to simulate the performance of different fracturing fluids and fracture designs to maximize the effectiveness of the SRV and thereby increase well productivity and EUR and reduce the overall cost of drilling horizontal wells.
• Recommendations and guidelines on the best way to fracture long horizontal wells for a given set of reservoir conditions.

Participants involved in the project: