Rangely is Colorado’s largest oil field: a great Weber sandstone anticline in Rio Blanco County, near the Utah line, that has produced on the order of 900 million barrels of oil and 700 billion cubic feet of gas. Shallow oil was known here from the early 1900s, but the deep Weber discovery by the California Company — today’s Chevron — in 1933 defined the field. Unitized as the Rangely Weber Sand Unit, it was waterflooded from 1958 and has run one of the country’s benchmark CO2 miscible floods since 1986.
Settlers and early drillers found shallow oil in the Mancos shale near the town of Rangely in the early 1900s, but the field’s true scale emerged in 1933, when the California Company’s deep test found oil in the Weber sandstone thousands of feet below. The Depression and remoteness deferred development; it took wartime demand in 1943 to launch the drilling campaign that proved a giant, with initial 40-acre development completed by 1949 and the boomtown of Rangely rising alongside the derricks.
The field’s operators unitized as the Rangely Weber Sand Unit in the 1950s, and a full-scale waterflood began in 1958, driving production to a peak of roughly 82,000 barrels a day. As the waterflood matured, Chevron prepared the next step: in October 1986 the unit began miscible CO2 injection in a water-alternating-gas scheme, with pipeline CO2 delivered from ExxonMobil’s LaBarge gas processing complex in Wyoming. Ultimate incremental recovery from the CO2 project was estimated at over 100 million barrels.
Rangely became one of the most-studied CO2 floods in the world — host to foam trials, monitoring programs, and decades of published performance reviews — while remaining Rio Blanco County’s economic anchor. After operating the field for some nine decades, Chevron sold the Rangely Weber Sand Unit to Scout Energy Partners, which now operates the flood and continues development of a field whose cumulative production stands near 950 million barrels.
Rangely produces from the Weber sandstone, a thick Pennsylvanian–Permian eolian and marine sandstone folded into a large, well-defined anticline on the eastern edge of the Uinta Basin trend in northwestern Colorado. The Weber’s great thickness and areal extent made the field a giant, while its moderate permeability and internal layering made engineered flooding essential: water and CO2 must be routed carefully through the sandstone’s stratified intervals to sweep efficiently. Shallow Mancos oil overlies the structure but has always been a footnote to the Weber.
Rangely is a global reference case for CO2 flooding in sandstone. The 1986 water-alternating-gas project, layered onto a waterflood then nearly thirty years old, was designed around a 30 percent hydrocarbon pore-volume CO2 slug and has recovered incremental oil estimated well above 100 million barrels, sustained by CO2 piped from Wyoming for nearly four decades. Continuous surveillance — including pioneering CO2-foam trials — has kept the flood improving with age. Royalty owners here are paid on production that exists because injection keeps being funded, year after year.
Rangely interests offer what few royalty streams can: scale, operating history measured in generations, and a recovery mechanism with decades of documented performance. They also require specialized valuation — CO2-flood tails, CO2 supply economics, and unit accounting all shape what an interest is genuinely worth, and generic decline-curve pricing gets it wrong. We buy minerals and royalties in Rio Blanco County directly and provide free written offers that lay out our flood-based valuation openly.
County-level well data, production charts, and selling guides for the counties this field spans:
Chevron, whose predecessor the California Company discovered the Weber pay in 1933, operated the Rangely Weber Sand Unit for roughly ninety years before selling to Scout Energy Partners, which now owns and operates the unit and its CO2 flood.
Rangely has already produced on the order of 900 million barrels across nine decades, and its CO2 flood — running since 1986 — continues to recover oil waterflooding left behind. CO2-flood giants decline slowly, and remaining life is governed more by injection economics than by any imminent geologic limit.
It depends on your decimal in the unit, the flood’s performance in your tract participation, and how a buyer models the long CO2-supported tail. That modeling is where offers diverge most. Send us your division order or check stub and we will provide a free written offer with the assumptions shown.