The Keystone Field in Winkler County, Texas is one of the Central Basin Platform’s great stacked-pay accumulations — a single structural culmination that produces from shallow Permian sands all the way down to the Ordovician Ellenburger. Opened in 1935 and famously associated with wildcatter Sid Richardson’s early fortunes, Keystone grew pay zone by pay zone as deeper drilling through the 1940s and 1950s found oil in the Devonian, Silurian, and Ellenburger. Cumulative recovery estimated in the hundreds of millions of barrels makes this some of the most storied mineral acreage in Winkler County.
Source: Texas Railroad Commission production filings, aggregated across RRC field designations 49129150, 49129396, 49129066, 49129330, 49129132. Reported volumes lag the calendar by several months.
Keystone was discovered in 1935, opening shallow Permian pay on the Keystone structure north of Kermit in a county already proven by the 1926 Hendrick boom. Sid Richardson leased aggressively in the new field, and by the end of 1940 held 33 producing wells there — production that helped build one of the legendary Texas oil fortunes. The shallow Colby sand development of the late 1930s established the field; the structure beneath it held far more.
Deeper exploration transformed Keystone in the 1940s and 1950s. Wells drilled down the flanks and crest of the buried structure encountered productive Devonian, Silurian, and ultimately Ellenburger dolomite, stacking half a dozen distinct reservoirs above one another in the same footprint. Each horizon was developed and regulated as its own reservoir, giving the field an unusually complex unit and lease architecture — and giving mineral owners under the structure multiple pays contributing to their royalty streams over time.
As the major zones matured, operators turned to pressure maintenance and secondary recovery, applying waterflooding and gas injection across the principal units in the post-war decades. The field settled into the long, managed tail characteristic of Central Basin Platform giants: consolidation under fewer operators, selective workovers and recompletions among the stacked zones, and steady production that has now spanned nine decades of Winkler County history.
Keystone sits on a large, deeply rooted structural high on the northern Central Basin Platform. Shallow Permian sands like the Colby produce at modest depths, while the underlying section steps down through Devonian and Silurian carbonates into the Ordovician Ellenburger dolomite — one of West Texas’s classic deep reservoirs. Stacked pays on a single structure are what make the field remarkable: one tract of minerals can be productive from several geologic systems separated by hundreds of millions of years, each with its own pressure regime, recovery mechanism, and production history.
Keystone’s longevity comes less from a single signature flood than from serial redevelopment of its stacked reservoirs. Waterflooding and gas injection sustained the major Permian and deeper units after primary depletion, and recompletion opportunities among multiple pay zones have repeatedly given old wellbores new life. For royalty owners this diversity is a quiet advantage: production does not depend on one reservoir’s decline curve, and the field’s recovery history suggests operators have consistently found economic reasons to keep investing in the structure rather than abandoning it.
Minerals under a stacked-pay field like Keystone are more complex — and often more valuable — than a single-zone interest, because multiple reservoirs and units may pay on the same acreage over time. That complexity also means owners frequently hold fragmented interests across several units without a clear picture of what each contributes. Before selling, it pays to understand exactly which zones and units your decimal touches. We buy minerals and royalties in Winkler County and provide free written offers.
County-level well data, production charts, and selling guides for the counties this field spans:
Yes. Keystone has produced since 1935 and remains active, with its stacked reservoirs — from shallow Permian sands to the deep Ellenburger — managed as mature units under waterflood and pressure-maintenance programs.
Regulators treat each producing horizon as a separate reservoir, so the same surface tract can sit in several designated fields — for example a shallow sand unit and a deeper Devonian or Ellenburger unit. Your division orders list each one separately.
Confirm your ownership and unit decimals from deeds and division orders, then obtain a written offer that values every producing zone, not just the most visible one. We evaluate stacked-pay interests directly and provide free written offers.