North Cowden Unit

The North Cowden Unit (NCU) is a large-scale CO₂-enhanced oil recovery (CO₂-EOR) project located in Ector County, Texas, on the Central Basin Platform of the Permian Basin. The field produces primarily from Permian-age San Andres Formation carbonates, consisting of dolomitized shallow-water platform deposits characterized by layered porosity, moderate-to-high permeability, and significant heterogeneity. Initially developed under primary depletion followed by extensive waterflooding, the North Cowden Unit transitioned to tertiary recovery through miscible CO₂ injection beginning in the late 1990s to early 2000s. The CO₂ flood targets residual oil saturation remaining after secondary recovery and improves sweep efficiency using pattern injection and water-alternating-gas (WAG) strategies. The project is frequently cited as a leading example of modern Permian Basin CO₂-EOR development and integrated CO₂ storage, combining incremental oil recovery with long-term geologic sequestration.