The Means Field in Andrews County, Texas is one of the Permian Basin’s most studied oilfields — a San Andres and Grayburg carbonate reservoir discovered in 1934 on the eastern edge of the Central Basin Platform, about 50 miles northwest of Midland. Means has been produced by primary depletion, waterflood, and a full-scale CO2 water-alternating-gas (WAG) flood that became a benchmark for the industry. For mineral owners, that ninety-year progression matters: each recovery stage reset the field’s decline curve and extended the life of the royalty stream beneath it.
Source: Texas Railroad Commission production filings, aggregated across RRC field designations 60137001, 60137500, 60139500. Reported volumes lag the calendar by several months.
Means was discovered in 1934 along a trend of San Andres production that runs more than 100 miles down the eastern flank of the Central Basin Platform. Development proceeded on 40-acre spacing through the 1930s and 1940s, with Humble Oil & Refining building the dominant position. Shallow depths and thick carbonate pay made the field a steady, low-cost producer through the primary era, and it became one of the anchors of the Andrews County oil economy.
As reservoir pressure declined, the field was unitized to enable secondary recovery, and the Means San Andres Unit became the vehicle for a large-scale waterflood in the 1960s and 1970s, followed by infill drilling programs that tightened spacing and captured bypassed pay. Exxon’s engineers used Means as a proving ground for evolving reservoir-management practice, publishing a series of influential technical papers that traced the field’s response to each new phase of development.
The modern era began in November 1983, when CO2 injection commenced in a full-scale tertiary project run at a 1:1 water-alternating-gas ratio — a design expected to recover more than 38 million additional barrels. The Means CO2 WAG became a canonical case study in enhanced oil recovery, and the field has continued producing under an integrated program of CO2 injection, waterflooding, and infill drilling, with operatorship in recent years associated with mature-asset specialists.
Means produces from the San Andres and Grayburg dolomites at moderate depths on the eastern Central Basin Platform. The reservoir is a stacked sequence of shallow-water Permian carbonates — porous dolomite intervals separated by tighter beds — that holds a very large volume of original oil in place but gives it up reluctantly. Heterogeneous, layered rock like this leaves significant oil behind both primary production and waterflooding, which is precisely why Means justified a full-scale miscible CO2 flood: the remaining target was measured in tens of millions of barrels.
Means is one of the classic CO2 WAG floods in American oil history. Injection began in 1983 after two decades of waterflooding, alternating slugs of CO2 and water to sweep residual oil the water alone could not move. Projects like this are engineered around multi-decade paybacks, and Means has now been under tertiary recovery for more than forty years. For royalty owners the implication is direct: the field’s economics were rebuilt around long-horizon incremental recovery, and royalty interests participate in every one of those incremental barrels at zero cost.
A Means-area royalty is backed by ninety years of production and a tertiary flood designed to keep recovering oil for decades. Interests tied to large, actively managed units like the Means San Andres Unit deserve valuation that accounts for flood response and shallow terminal declines — not a quick multiple on last month’s check. If you have inherited or long-held minerals here, understanding your unit participation is the first step. We buy minerals and royalties in Andrews County and provide free written offers.
County-level well data, production charts, and selling guides for the counties this field spans:
Yes. Means has produced continuously since 1934 and remains under active CO2 water-alternating-gas injection combined with waterflooding and infill drilling — a program engineered for long-term, sustained recovery.
Humble Oil and its successor Exxon developed the field and ran its celebrated waterflood and CO2 WAG programs, publishing benchmark reservoir-management studies along the way. Operatorship of the mature units has in recent years been associated with companies specializing in legacy conventional assets.
It depends on your decimal in the unit, current production, and the flood’s expected tail — which for CO2 projects can run decades. Flood-supported royalties typically decline slowly, so obtain a written valuation built on the full recovery profile before selling.