Recovery of bypassed oil in the Dundee Formation using horizontal drains. Annual report, March 1996--March 1997

This Class II field project has demonstrated that economic quantities of hydrocarbons can be produced from abandoned or nearly abandoned fields in the Dundee Formation of Central Michigan using horizontal drilling technology. The site selected for the demonstration horizontal well was Crystal Field, a nearly abandoned Dundee oil field in Montcalm County, Michigan. This field had produced over 8 million barrels of oil, mostly in the 1930`s and 1940`s. At the height of development, Crystal Field produced from 193 wells, but by 1995, only seven producing wells remained, each producing less than 10 bbls/day. A horizontal well, the TOW 1-3, drilled as a field demonstration pilot was successful, producing at rate of 100 bbls of oil per day with a zero water cut. Although the well is capable of producing at a of 500+ bbls/day, the production rate is being kept low deliberately to try to prevent premature water coning. Cumulative production exceeded 50,000 bbls of oil by the end of April, 1997 and lead to the permitting and licensing of several dozen Dundee wells by project end. Twelve of these permits were for continued development of Crystal Field. Two long horizontal wells were drilled successfully in Crystal after the TOW 1-3, but were disappointing economically. Core and logs from the Dundee interval were recovered from a vertical borehole at the same surface location. The addition of several horizontal wells will likely add another 2 million bbls (or more) to the cumulative production of the field over the next few years. If other abandoned Dundee fields are re-developed in a similar manner, the additional oil produced could exceed 80 million barrels