Basin Detail
The Greater Green River Basin covers roughly 21,000 square miles of southwestern Wyoming and reaches into northwestern Colorado and northeastern Utah. It is really four connected basins — the Green River Basin proper, the Great Divide, the Washakie, and the Sand Wash — and it holds more than three hundred named fields, most of them gas. Two kinds of property sit side by side here: long-established conventional oil and gas fields such as Wertz, and the dense tight-gas developments of the Pinedale Anticline and Jonah Field in Sublette County. Both are mature. Drilling has slowed sharply from its peak and most acreage is now held by production. We buy mineral rights, royalty interests, NPRI, and ORRI across the Greater Green River Basin.
Approximate location of the Greater Green River Basin shown in tan
Basin-level activity chart not yet available for the Greater Green River Basin. For current activity, see our rig count dashboard and the state production pages linked above.
The Greater Green River Basin holds a very thick Cretaceous and Tertiary section, and most of its gas comes from tight sandstones rather than from conventional traps. At Jonah and on the Pinedale Anticline the productive interval is a stack of lenticular fluvial sands in the Lance and upper Mesaverde, three thousand feet or more of section that has to be hydraulically fractured in many separate stages before it will flow. Along the Wamsutter and Washakie trends the Almond, Frontier, and Mesaverde sandstones produce. Conventional oil is older and shallower, coming from Paleozoic reservoirs on structures around the basin margins, with the Phosphoria and Mowry shales recognized as principal source rocks. Low permeability defines the gas side of the basin: reserves per well can be substantial, but nothing produces without stimulation.
Operatorship on the big tight-gas fields has changed hands repeatedly. Jonah was discovered by McMurry Oil, which drilled the field's 1993 discovery well, and the position later passed to larger public companies including EnCana and Ultra Petroleum during the drilling boom. Both Jonah and Pinedale have since moved again, and the companies holding them now run maintenance-scale programs focused on keeping existing wells producing rather than on adding pads. Conventional oil fields around the basin margins are held by independents that specialize in mature, injection-supported properties. For a mineral owner the practical consequence is that operator capital budgets, not geology, determine whether anything new gets drilled on your acreage in a given year.
Greater Green River values are mostly a function of gas: the volume your wells still produce, the shape of the decline, and the price those volumes actually realize. Rockies gas trades at a basis differential to national benchmarks, and gathering, compression, processing, and transportation charges are frequently deducted before royalty is calculated, so the net-back on a check can be well under the quoted price. Tight-gas wells decline hard in their early years and then settle into a long, shallow tail, which makes an old well more predictable than a new one. Most acreage in the core is held by production under decades-old leases, so the value in a typical interest is in the wells that already exist.
Tight-gas wells produce a large share of their total recovery early. A new Lance or Mesaverde well can lose a substantial part of its rate within the first two years, then flatten into a long, slow decline that lasts for decades. If your interest was created when a pad was fresh, the drop you saw was the normal shape of the curve rather than a problem with the well. Gas price movements amplify it, because a lower price applied to a lower volume compounds. The useful question for valuation is not what the check was at peak but what the last two or three years of the tail look like.
It does. Value in a mature gas basin comes mainly from wells that are already producing, and a long, flat tail on an existing well is easier to underwrite than a promise of future drilling. What matters is the current monthly volume, the decline rate, the royalty fraction, and whether the lease is held by production. Undrilled potential is worth something, but in an area where operators are running small programs it carries a discount, because there is no way to know when or whether a location gets built. We value the production you have now and treat any future drilling as upside rather than as the basis of the offer.
Quoted gas prices are for delivery at a national benchmark point. Wyoming gas sells into regional markets that have historically traded at a discount to that benchmark, and it has to be gathered, compressed, dehydrated, processed for liquids, and shipped before it reaches a market. Depending on how your lease is written, some of those costs may be deducted from your royalty. The price you see on your statement is what remains after all of it. Reading the deduction lines on your check detail is worth the effort, because two owners in the same field can net very different amounts purely because of differences in lease language.