A maximum of 3,566 blocks located in the Mid-Atlantic Continental Shelf and Slope could be offered for lease in the proposed Mid-Atlantic Lease Sale No. 111 scheduled for October 1985. The standard block size in the Atlantic is 5,693 acres (2,304 hectares) or approximately 9 square mi. The blocks under consideration for lease comprise a total area of roughly 20 million acres. If held, this would be the fifth lease sale in the Mid-Atlantic Planning Area (not including sales in what was previously the South Atlantic Planning Area). This offering represents approximately 25 percent of the total area in the Mid-Atlantic Planning Area but includes approximately 60 percent of the region's estimated oil and gas resources. Based upon proprietary geophysical data, well data, and the process described below, the Minerals Management Service has estimated that a mean of 200 million bbl of recoverable oil and 3.6 tcf of recoverable natural gas may exist in the sale area. These resource estimates are based upon the assumption of the existence of recoverable hydrocarbon accumulation in the area. The development of these resource estimates is described in Appendix B. A high and a low resource estimate, representing the 5th and 95th percentile of the conditional resource distribution, respectively, and mean resource estimates for the proposed action as well as a mean resource estimate for all the alternatives to this sale, have been developed as well (see Table II.B.1-1). Changes to the impacts which could result under the high resource estimate are discussed in section IV.0; impacts resulting under the low resource estimate are discussed in section IV.P. The production schedules associated with the mean, high, and low estimates described above are given in Tables II.A.1-1, 1-2, and 1-3. Based on the mean estimate oil production is projected to begin in 1995 followed 3 years later by the first gas production. Production of both oil and gas in the mean case is projected to continue through the year 2021. The peak daily rate of production associated with the mean estimate is approximately 52,000 bbls of oil in 1999 and approximately 1.2 bcf of gas in the year 1999. Resource estimates for the proposed action, as well as for all alternatives, have been produced by MMS in a three-step process. The first step in the process consists of identifying geologic structures and traps (areas which may contain oil and gas) in the proposed sale area or in one of the alternative sale areas. These prospects are identified and mapped by using geophysical data obtained from seismographic studies, as well as data from previous drilling in the region. Once all the potential areas of oil and gas have been identified and mapped, MMS utilizes a computer model to estimate the amount of oil and gas contained in each individual trap (see Appendix B for more details). The final step in the process consists of comparing the individual trap resource estimates obtained from the computer model with a minimum economic field size estimate (amount of oil or gas necessary to make recovery economically possible). |