Pinedale Field

Ultra Petroleum is the dominant operator in Pinedale Field, one of the top ten natural gas fields in the United States.

Ultra controls more than 105,000 gross (69,000 net) acres in and around the prolific Pinedale and Jonah Fields in southwest Wyoming’s Sublette County.  The two field complexes produce from the Upper Cretaceous-aged Lance and Mesaverde Formations, and together cover an area 30 miles long by 6 miles wide.  In 2016 they combined to produce an average of 711 MMCFE (net) of natural gas and condensate per day.  Ultra operates 90% of its acreage position with an average working interest of 83.7%, owns an interest in over 2,500 producing wells in the field, and the vast majority of Ultra's acreage is held by production.  Ultra is the top natural gas producer in the State of Wyoming.

The Bureau of Land Management (BLM) issued the Pinedale Record of Decision (ROD) in September 2008. Under the ROD, Ultra Petroleum gained year-round access to Pinedale for drilling and completion activities in development areas. This additional access resulted in increased drilling efficiencies and allowed for accelerated development of the field.


Ultra Petroleum's premier acreage position is in the prolific Lance and Mesaverde Formation tight-gas sand plays in southwest Wyoming.

Ultra’s premier position in the Pinedale and Jonah Fields is located in southwest Wyoming near the town of Pinedale in Sublette County.  It lies in the heart of the Lance and Mesaverde Formation tight gas sand play in the northern part of the Green River Basin.  It is surrounded to the east, north and west by the Wind River, Gros Ventre and Salt River mountain ranges respectively.


Pinedale Field is a very large natural gas accumulation in the Upper Cretaceous Lance and Mesaverde Formations.

Productive sandstones from the Lance and Mesaverde Formations comprise the Lance Pool, a natural gas resource, at subsurface depths ranging from 10,000 to 14,000 feet in Pinedale. This thick sequence of over-pressured sands developed 65 million years ago when a braided river system brought eroded sediments down from the surrounding mountains and deposited them in the Green River Basin. Subsequent to deposition, continued mountain building events led to the development of a large structural high under the Pinedale and Jonah Field areas.  This geologic structure is responsible for trapping the large natural gas deposits that are thickest in Pinedale.

Ultra is utilizing surface pad technology to develop the field, typically drilling 20 to 25 vertical wells from individual pad sites strategically located across the field.  Numerous stacked reservoirs in the pay interval make vertical wells the most efficient method of development.  Multi-stage fracture stimulation completions, refined and improved over time by Ultra engineers, have resulted in increased well performance.


An Ultra Petroleum success story.

During the field’s early years, many wells encountered natural gas shows, and some were capable of producing gas at rates up to one million cubic feet per day, but most only produced a fraction of that amount. The limited economic success of the early wells was the result of poor geologic understanding and ineffective completion technology. As a result, the Pinedale/Jonah structural complex remained largely ignored until 1995 when the first successful well in Jonah Field was completed.

In 1997, Ultra drilled the Mesa 15-8 well in the northern part of Pinedale Field. This well, along with other successful wells drilled the same year by McMurry Oil, marked the birth of successful development in Pinedale and Jonah Fields.  Both fields have been under aggressive development ever since.

Ultra aggressively acquired leasehold over Pinedale Field in 1997, and now owns by far the largest acreage position over this prolific field, more than four times the next largest owner.  All of the acreage that Ultra's technical team considers prospective, over 75% of the total, is held by production with no risk of expiration.  This enables Ultra to develop the resource in a very efficient and economically advantageous manner without being driven by leasehold management concerns.  In 2008, the Bureau of Land Management (BLM) issued the Pinedale Record of Decision (ROD) that provided Ultra year-round access to the field for drilling and completion activities. This additional access has led to increased drilling efficiencies and allowed for an accelerated development plan.  The Wyoming Oil and Gas Conservation Commission (WOGCC) has approved field-wide drilling on 5-acre spacing, which will ultimately lead to more efficient development and higher over-all gas recovery from the field.