부산대학교 도서관

Lower Cretaceous Muddy and Upper Cretaceous Frontier sandstone reservoirs remain popular objectives for new energy reserves in the Bighorn basin of northwestern Wyoming. Predominantly structural reserves approximate 1 million bbl of oil and 20 bcf of gas from six Muddy fields, and 210 million bbl of oil and 100 bcf of gas from 16 Frontier fields. Newly established structural-stratigraphic gas production from these reservoirs is at Meeteetse field (T48-49N, R99W) on the west flank of the basin where Muddy Frontier bar sandstones trend across a long, narrow, horst-associated anticline. Terra Resources 1-33 Federal (Sec. 33, T49N, R99W) established the shallower pool discovery in 1979. Ten wells are now drilled along or near the axis of the structure. Production history is only now beginning because wells were shut in during field development due to absence of a gas line. The Frontier is productive in the middle two of its four units. Most initial production rates are between 1 and 2 MMCFGD; small amounts of oil, condensate, and water have been produced from some wells. The Muddy is a discrete sandstone unit with thin shale interbeds. Most initial production rates are between 1 and 3 MMCFGD; small amounts of oil, condensate, and water are also produced. Some production is from commingled Frontier zones and from commingled Frontier and Muddy.