About the Fayetteville Shale

An introduction to the Fayetteville Shale including its location and geographic extent, economic importance, and physical characteristics.

The Fayetteville Shale is an unconventional natural gas reservoir located on the Arkansas side of the Arkoma Basin, ranging in thickness from 50 to 550 feet and ranging in depth from 1,500 to 6,500 feet. The shale is a Mississippian-age shale that is the geologic equivalent of the Caney Shale found on the Oklahoma side of the Arkoma Basin and the Barnett Shale found in north Texas.

Location The Fayetteville Shale play stretches across Arkansas from approximately Fort Smith east to beyond Little Rock, Arkansas. It is approximately 50 miles wide from north to south. The figure shows those counties that have some wells drilled to the Fayetteville Shale formation. The most active area of natural gas development is from western Conway County through eastern White County. Development further to the east is anticipated to proceed very slowly because the shale is considerably deeper, making gas extraction less economical.

Economic Importance

The Fayetteville Shale is important to Arkansas because it holds large quantities of natural gas. Unlike more traditional oil and gas fields that contain hydrocarbons in porous rock formations, shale holds natural gas in a fine-grained rock matrix. Until recent years, most shale formations were not considered profitable areas for gas production. With new technology and elevated natural gas prices, companies have made the Barnett Shale play in north Texas one of the hottest production fields in the country. Encouraged by the success in the Barnett Shale formation, operators looked at other large shale formations, including the Fayetteville Shale.

Geologists describe the Fayetteville Shale formation as tight, which means it requires fracturing to produce economic quantities of gas. The most prolific gas production from the Fayetteville Shale is associated with horizontal wells that have been completed with multi-stage fracture jobs in the middle to lower portions of the formation. Click to enlarge the figure at right which shows the major stratigraphic layers surrounding the Fayetteville Shale layer. (Graphic courtesy of Chesapeake Energy, Inc.)

Shale Formation Click to enlarge

At the end of 2007, there were approximately two million acres under lease to production companies in the play. It is anticipated that thousands of wells will be drilled during the next several years. This activity will include construction and installation of roads and pipelines, as well as drilling fluid disposal pits and infrastructure to handle hundreds of millions of gallons of fracturing fluids.