A miscible CO2 flood pilot conducted in the Maljamar field, New Mexico, was formally completed January 1, 1986. This paper presents the results and developments of numerically history matching the 6th (Grayburg) and 9th Massive (San Andres) zone CO2 pilots. The purpose of this pilot was to gain information that would reduce the operational and economic uncertainties of a full-scale project. Special features of the 5-acre (20,200 m2) inverted 5-spot pilot include (a) dual (separate) completions in the Grayburg and San Andres zones and (b) two fiberglass-cased logging observation wells for in situ monitoring of oil, brine, and carbon dioxide movement. The logging observation wells illustrated that the miscible CO2 flood process can significantly reduce oil saturations in the 6th and 9th Massive zones at Maljamar. The high CO2 retention, high minimum water saturation, and low CO2 injectivity exhibited in the pilot can be accounted for through relative permeability hysteresis and a possible change in rock wettability. By incorporating these mechanisms into the simulator, a reasonable match of oil and CO2 production, fluid injectivity, and observation well saturation profiles demonstrated the validity of the approach. The calibrated performance parameters were used as a basis for making fieldwide performance predictions for the Maljamar field.

You can access this article if you purchase or spend a download.