Unique Through-Fracture Core Data from HFTS Provides Knowledge that Will Fundamentally Alter the Understanding of Hydraulic Fractures

In an $18 million project sponsored by a public-private partnership, Gas Technology Institute (GTI) is collaborating with experts from industry and government on a Hydraulic Fracturing Test Site (HFTS). The effort is targeting horizontal shale wells to reduce and minimize potential environmental impacts, demonstrate safe and reliable operations, and improve the efficiency of hydraulic fracturing.

This GTI-led program will validate and advance fracture diagnostic technologies such as microseismic acquisition and analysis techniques for more accurate determination of fracture dimensions. Field data acquisition and environmental and microbiological research tasks to monitor air and water quality at the HFTS have been completed.

A one-of-a-kind through-fracture core was drilled through the hydraulic fractures at the test site, providing a core sample where the physical properties of the fractures can be observed. This 600 feet of core will be invaluable in validating fracture models and verifying data analysis.

A comprehensive hydraulic fracturing data set has been collected, unlike anything ever captured before in unconventional shale. It is providing a first-ever look at how induced underground fractures spread, and will fundamentally alter the understanding of hydraulic fracture propagation, modeling, and effectiveness.

With significant long-term shale production planned in the U.S., environmental concerns remain, and it is widely recognized that hydraulic fracturing must be driven by efficiency that lowers environmental impact.

Current hydraulic fracturing operations can be made more efficient. Prior work has shown that production from many fracture stages is negligible, with about half of the stages producing the majority of the hydrocarbons. Data from the HFTS will be used to assess the results of individual fracture stages. Improved design and execution of hydraulic fracturing will reduce the number of future wells drilled and reduce water volume and energy input, resulting in a smaller environment footprint associated with shale drilling.

Microbial impacts on biological corrosion and reservoir quality deterioration will also be investigated; and changes in properties of shallow aquifers, flow-back, and formation water resulting from hydraulic fracturing will be evaluated.

The test was hosted at a Laredo Petroleum, Inc. (LPI) Permian basin field in west Texas, where 400+ fracture stages were completed in 11 wells in the Wolfcamp formation. LPI also provided critical geological and reservoir data from many wells in the area. "Laredo is honored to perform such an important role operating this project," states James Courtier, Vice-President Exploration & Geoscience Technology at Laredo Petroleum. "Data collected not only has improved our understanding of the subsurface, but will be vital in developing technological advances to maximize economic development of the vast oil shale resources in the Midland Basin."

Funding is being provided by the U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) and numerous operators and service companies, including Core Laboratories, Devon, Discovery Natural Resources, Encana, Energen, Halliburton, and TOTAL. Industry contributed background information necessary for research on all aspects of hydraulic fracturing, estimated at over $100 million.

"This program is critical to the industry—as illustrated by the substantial funding support from our collaborators—and will be beneficial to our world at large," says Kent Perry, Executive Director of Energy Supply R&D at GTI. "We will gain new technologies and techniques to minimize environmental impacts and optimize fracturing, leading to safer and more prudent development of unconventional resources."