The TXL Field takes its name from the acreage it was found on. Shell Oil and Cities Service drilled the 1944 discovery on Texas Pacific Land Trust ground in northwest Ector County, the lease was styled "TXL," and the name stuck — a decade later Texas Pacific Land used the same shorthand when it formed TXL Oil Corporation. What the partners found was not one reservoir but a column of them: seven separately designated Railroad Commission reservoirs from the San Andres at 4,380 feet down to the Ellenburger at 9,600, together making roughly 270 million barrels.
Source: Texas Railroad Commission production filings, aggregated across RRC field designations 88071696, 88071232, 88071290, 88071580, 88071174. Reported volumes lag the calendar by several months.
The discovery came in 1944, credited jointly to Shell Oil Company and Cities Service Oil Company and reported in contemporaneous Big Spring newspaper coverage as a northwest Ector County wildcat on Texas Pacific Land Trust acreage that was later deepened past 9,428 feet toward the Ellenburger. The AAPG Bulletin described the Devonian chert reservoir the following year as probably one of the most interesting types of reservoir rock discovered — a technical compliment that reflected how little chert pay of that quality had been seen in the basin.
Development was extraordinarily fast. By November 1, 1945, barely a year after discovery, twenty-four Devonian wells and two Ellenburger wells were complete with roughly thirty-five rigs running in the field. The reservoirs were then added one by one over the next quarter century: Silurian in 1946, Ellenburger in 1949, Tubb in 1950, San Andres in 1952, Pennsylvanian in 1956, and a Devonian Main Pay designation in 1970. Each has its own Railroad Commission field name, discovery year and depth.
The Ellenburger turned out to be the prize, producing roughly 130 million barrels — nearly half the field total — against about 59 million from the original Devonian and 57 million from the Tubb. In 2010 operators returned to the shallower section with horizontal wells: laterals in the Clearfork and Tubb at roughly 5,800 to 6,300 feet in the TXL South Unit reported initial rates in the range of 200 to 500 barrels a day. TXL is a multi-operator field rather than a single-company property.
TXL is a Central Basin Platform structure with pay stacked across more than 5,000 feet of section. At the top sits San Andres dolomite around 4,380 feet, then the Tubb at about 6,158 feet, then Devonian chert near 8,050 feet — the reservoir that drew AAPG attention in 1946 — with Silurian carbonate just below and the Ordovician Ellenburger at roughly 9,600 feet. The Ellenburger here is karsted: the Gulf 000-1 TXL well is used as a type example of Ellenburger karst-collapse facies in regional Bureau of Economic Geology work.
Because TXL is seven reservoirs rather than one, recovery history varies by pay. The shallower Clearfork, Tubb and San Andres intervals have been developed through unit operations and secondary recovery, while the deep Devonian and Ellenburger carbonates behave as separate pressure systems with their own histories. The clearest modern chapter is horizontal redevelopment: Clearfork and Tubb laterals drilled in the TXL South Unit around 2010 at roughly 5,800 to 6,300 feet reported initial production between about 200 and 500 barrels a day.
TXL is one of the strongest arguments in the basin for reading a deed before accepting an offer. With seven designated reservoirs spanning 4,380 to 9,600 feet under the same surface, depth severances in a chain of title change value dramatically, and many owners are paid from one shallow reservoir while holding rights in several more. Horizontal redevelopment of the shallow pay adds a second question about which intervals are actually being worked. We buy minerals and royalties in Ector County and provide free written offers.
County-level well data, production charts, and selling guides for the counties this field spans:
It comes from Texas Pacific Land. The 1944 discovery was drilled on Texas Pacific Land Trust acreage and the lease was styled TXL, which became the field name; Texas Pacific Land later used the same abbreviation when it created TXL Oil Corporation in 1954 to hold the mineral estate under its West Texas acreage. It is not related to any cattle company, despite the resemblance.
Quite possibly. The Railroad Commission carries seven separate TXL reservoirs, and a mineral owner without a depth severance in the chain of title owns all of them beneath their tract, whether or not each one is currently producing to their credit. Non-producing intervals still carry value. Checking which designations your tract falls under is a routine part of preparing an offer.
They pay whoever holds the royalty under the lands the lateral traverses, allocated under the applicable lease and any pooling or unit agreement. If a lateral crosses your tract or your tract is in the participating unit, you should see it. If it is drilled on adjacent acreage under a separate lease, you will not. Your check detail and the well permit together answer this.