The Bakken formation
Geology, footprint, and mineral-owner context for the Bakken, drawn from public USGS and state survey sources. Resource figures describe the play as a whole and are not a per-acre value. Every figure on this page is an estimate subject to verification of your specific interest.
Last updated June 2026.
What is the Bakken?
The Bakken is the Devonian to Mississippian shale-and-siltstone interval of the Williston Basin that launched the modern American shale-oil era, concentrated in McKenzie, Mountrail, Williams, and Dunn counties in western North Dakota. The USGS assessed the Bakken and the underlying Three Forks together at a mean of about 4.3 billion barrels of undiscovered, technically recoverable oil in its 2021 update, a play-wide figure rather than a per-acre yield.
The Bakken is the formation that started the shale-oil boom. It sits in the Williston Basin of western North Dakota and eastern Montana and is classically described in three parts, an upper and lower organic-rich shale that source the oil and a middle dolomitic siltstone and sandstone that holds and produces most of it. The thickest, most over-pressured Bakken sits under McKenzie, Mountrail, Williams, and Dunn counties, which is why those counties are consistently among the top oil producers in the country. The basin is now mature, so most of the prime locations are drilled and value rests mainly on existing production. For mineral owners, a Bakken royalty is typically a seasoned, flatter-declining income stream, valued on the standard income multiple applied to your real checks.
Bakken geology
- Age and lithology
- Late Devonian to Early Mississippian, with upper and lower organic-rich shale members and a middle dolomitic siltstone and sandstone reservoir member. Source: USGS Williston Basin assessment.
- Paired with Three Forks
- The Bakken is developed together with the underlying Three Forks formation, so a single tract often produces from both intervals.
- Where it produces
- The Williston Basin: McKenzie, Mountrail, Williams, and Dunn counties form the core, with Divide, Burke, Billings, and others on the flanks.
How much oil and gas the Bakken holds
In 2021 the USGS assessed the Bakken and Three Forks formations of the Williston Basin to hold a mean of about 4.3 billion barrels of undiscovered, technically recoverable oil, plus associated gas and natural gas liquids. The 2013 assessment had put the combined figure near 7.4 billion barrels. These are undiscovered play-wide estimates, not proven reserves and not a measure of any individual property.
Source: USGS Fact Sheet 2021-3058 (Bakken and Three Forks, Williston Basin, 2021 update).
Counties in the Bakken play
These are the counties and parishes we cover where the Bakken produces. Each links to local value context and the operators active there.
What the Bakken means for your minerals
A resource estimate for a play is not the value of your acreage. Your mineral and royalty interest is valued on the income your wells actually pay, roughly 36 to 72 times your average monthly royalty check, the same as 3 to 6 times your annual royalty. Where you land in that band depends on your wells decline, the operator, your royalty rate, and any undeveloped drilling upside. For the full method and a free on-screen estimate, see what are my mineral rights worth.
The Bakken is part of the Williston Basin. For the basin-wide value bands and the counties we buy in, see the Williston Basin page.
Bakken questions
- What is the Bakken formation?
- The Bakken is a Devonian to Mississippian shale-and-siltstone oil interval in the Williston Basin of western North Dakota and eastern Montana. It launched the modern shale-oil boom and is concentrated in McKenzie, Mountrail, Williams, and Dunn counties.
- Is the Bakken still worth owning if the basin is mature?
- Yes. A mature Bakken well has usually settled into a flatter, more predictable decline, which can support a steady valuation on the income multiple even though there is less new-drilling upside than in the Permian. Many Bakken owners are out of state and prefer cash and a simpler estate.
- What does the Bakken resource estimate mean for my royalties?
- The USGS Bakken figure is an undiscovered, technically recoverable estimate for the whole play, not proven reserves and not a per-acre value. Your royalties are valued on the income your wells actually pay, roughly 36 to 72 times your average monthly check. This is an estimate, subject to verification, not an offer.
Sources
See what your Bakken minerals could be worth
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