Exxon Company, U.S.A., is actively drilling deep Anadarko Basin wells in the development of its Northeast Mayfield Field in Beckham County, Oklahoma. Two wells have been drilled to date and a third and last one is drilling at the writing of this paper. The first well, Walne 1-34, drilled to a depth of 25,825′ and was plugged back and completed in a limestone reservoir at 24,500′. The second well, Hazel Howell 1-2, drilled to a depth of 25,565′ and was also completed in the same limestone reservoir.
This paper presents a combined case history of the two wells mentioned above. In general, it briefly discusses both the geologic and drilling history of Northeast Mayfield and Exxon's basic drilling plans. Emphasis of the paper though, is focused on actual drilling operations and results. Specific drilling practices developed for the area, including those related to safety and the environment, are outlined. In addition, detailed discussion is included on a number of unique occurrences and successful operations in the course of drilling both wells. These include: 1) large nitrogen foamed cement jobs, 2) extended nozzle insert bit usage, 3) setting of a 5,800′, 24 ppg pill at casing seat point, 4) casing wear mitigation, 5) deep underbalanced drilling and, 6) a high pressure well control problem at 25,825′. In conclusion, the paper notes the key factors contributing to the success of these deep Anadarko Basin wells.