Fracking is concentrated in about a dozen major shale formations spread across more than 20 states, with the heaviest activity in Texas, Pennsylvania, New Mexico, North Dakota, and Oklahoma. These regions sit on top of massive underground rock layers rich in oil or natural gas that can only be extracted by pumping high-pressure fluid into the rock to crack it open.
The Major Shale Basins
The U.S. Energy Information Administration tracks several key shale plays where the vast majority of fracking takes place. Each basin has its own geology, and some produce mostly natural gas while others yield crude oil or a mix of both.
- Permian Basin (West Texas and southeastern New Mexico): The single largest oil-producing region in the country. It contains multiple stacked shale layers, including the Wolfcamp, Bone Spring, Delaware, and Spraberry plays. The Permian alone accounts for a massive share of total U.S. crude output.
- Marcellus Shale (Pennsylvania, West Virginia, Ohio): The dominant natural gas play in the eastern U.S., stretching across the Appalachian Basin. Pennsylvania is the epicenter, but drilling extends into northern West Virginia, where the top permit counties include Ritchie, Doddridge, Wetzel, and Marshall counties.
- Eagle Ford Shale (South Texas): A major oil and gas play in the Western Gulf Basin, running in an arc from the Mexican border northeast toward Houston.
- Bakken Shale (North Dakota and Montana): The formation that turned North Dakota into one of the top oil-producing states in the country, centered in the western part of the state.
- Anadarko Basin (Oklahoma and the Texas panhandle): Produces both oil and natural gas, overlapping with the Woodford Shale play underneath much of central and southern Oklahoma.
- Barnett Shale (North-Central Texas): Located in the Fort Worth Basin, this was one of the first shale formations to be commercially developed using modern fracking techniques.
- Utica/Point Pleasant Play (Ohio, Pennsylvania, West Virginia): Sits beneath the Marcellus in the Appalachian Basin and has become a significant gas producer in eastern Ohio.
- Fayetteville Shale (Arkansas): A natural gas play in the Arkoma Basin of northern Arkansas, though activity has slowed compared to earlier years.
Which States Have the Most Activity
Texas dominates. It hosts three major shale plays (the Permian, Eagle Ford, and Barnett) and produces more oil and gas than any other state by a wide margin. Pennsylvania ranks as the second-largest natural gas producer thanks to the Marcellus Shale, with thousands of active wells across the southwestern and northeastern parts of the state. New Mexico’s share has grown rapidly as Permian Basin drilling expanded westward across the state line from Texas.
North Dakota, Oklahoma, Colorado, Wyoming, Louisiana, and Ohio round out the most active fracking states. Louisiana’s Haynesville Shale, along the Texas border, is a major natural gas source. Colorado’s DJ Basin, north of Denver, produces both oil and gas. Wyoming has activity in several basins, including the Powder River Basin in the northeast.
States That Have Banned Fracking
As of 2024, five states have enacted statewide bans on hydraulic fracturing: Vermont (2012), New York (2014, solidified in 2020), Maryland (2017), Washington (2019), and California (2024). New York’s ban is notable because the Marcellus Shale extends into the southern part of the state, meaning significant gas reserves sit untouched just across the Pennsylvania border. Vermont and Washington had little to no fracking activity before their bans, making those laws largely precautionary.
Water Use and Wastewater Disposal
Each fracked well requires between 1.5 million and 16 million gallons of water, according to the U.S. Geological Survey. That wide range depends on the depth of the well, the type of rock, and the number of times the well is fractured. In arid regions like the Permian Basin, sourcing that water is a growing logistical challenge, and companies increasingly recycle produced water to reduce freshwater demand.
What happens to the wastewater afterward matters just as much as the fracking itself. Much of it gets injected into deep disposal wells, and that process has triggered earthquakes in several states. Oklahoma experienced a dramatic surge in seismic activity starting in 2009, including a magnitude 5.8 earthquake in central Oklahoma in September 2016, the largest injection-induced earthquake documented in the scientific literature at the time. The USGS has identified 17 areas in the central and eastern U.S. with elevated earthquake rates linked to wastewater injection. A magnitude 5.3 quake in Colorado’s Raton Basin in 2011 was also tied to fluid injection. Oklahoma has since tightened regulations on disposal well volumes, and earthquake rates have declined from their peak, though they remain above historical levels.
How Activity Shifts Over Time
Fracking doesn’t stay evenly distributed. Activity migrates based on oil and gas prices, pipeline capacity, and how much recoverable fuel remains in each formation. The Barnett Shale in Texas, once the poster child of the shale revolution, has seen drilling slow as companies shifted rigs to the more productive Permian Basin. The Fayetteville Shale in Arkansas followed a similar trajectory. Meanwhile, the Permian and Marcellus have only grown in dominance, and newer targets like the Utica play in Ohio continue to attract investment.
Rig counts, which measure how many drilling rigs are actively working, fluctuate month to month. They dropped sharply during the 2020 oil price crash and rebounded through 2022 and 2023, though they haven’t returned to pre-pandemic highs. Texas consistently runs more rigs than all other states combined.