Performance and Unitization of the Empire Abo Pool

Abstract Voluntary Unitization of 97% of the Empire Abo Pool, Eddy County, New Mexico, went into effect October 1, 1973. A reservoir study had shown that Unitization would mean recovery of an added 30 million barrels of oil. This would result from aiding the natural gravity drainage by shutting in high gas-oil ratio wells and returning available plant residue gas to the secondary gas cap. A later study showed further improvement in rates and recoveries by drilling additional development wells in low gas-oil ratio areas. Continuing engineering analysis and an aggressive attitude by the Unit owners has resulted in substantial increases in oil recovery and productivity as compared to continuation of productivity as compared to continuation of competitive primary operations. Introduction The Empire field is located about eight miles southeast of the city of Artesia in Eddy County, New Mexico (Fig. 1). The discovery well for the Empire Abo reservoir was the Amoco-Hondo Oil Company - Malco "A" No. 1, completed at what is now the Unit M-14 location (Fig. 2), in November 1957. Development moved rapidly to the west, east, and north from the discovery, which proved to be only one location removed from the fore-reef edge of productive limits of the reservoir. Within three years some 215 of the eventual 250 producing wells had been completed. In defining producing wells had been completed. In defining the reservoir, 29 dry holes were also drilled. Field performance before and after unitization is shown in Figures 3 and 4. Current pool producing rate for November 1976 is 41,700 BOPD, with the ARCO-Empire Abo Unit producing 41,062 BOPD of that total. Unit gas production in November was 55,746 MCFPD. Unit injection into the Abo gas cap in November was 34,451 MCFPD. Atlantic Richfield Company, with 34.14% interest, operates the Unit for the 112 working interest owners.