THE SYNERGETIC STUDY OF SILURIAN-NIAGARAN PINNACLE REEF BELT AROUND THE MICHIGAN BASIN FOR EXPLORATION AND PRODUCTION OF OIL AND GAS. (VOLUMES 1 AND 2)

The Silurian-Niagaran pinnacle reefs occur on a belt which encircles the entire Michigan Basin including areas presently covered by the Great Lakes Huron and Michigan.;The majority of the hydrocarbon reserves of the northern trend are concentrated in pinnacles which occur on a band 3-4 miles wide inside the middle of the trend. There exist a regional partitioning of oil and gas in the northern pinnacle reefs which can be best explained by Gussaw Theory of migration and differential entrapment.;A probabilistic model for exploration in play was found applicable in mature areas of the northern trend. The results were extended to other parts of the northern trend based on similar reef density and size distribution. In the southern trend where the reef density and size distribution is entirely different, the model was tested against limited data and results of future exploration were predicted. The effectiveness of exploration on the reef belt, based on seismic surveys, is 8 to 10 times better than random drilling.;The reserves of the reef belt is in excess of 7 billion barrels of oil and 15 trillion cubic feet of natural gas originally in place. The oil primary and secondary recovery factors are 20 and 30 percent respectively.;Two different structural settings existed in the Michigan Basin during the Silurian Period. This resulted in formation of pinnacle reefs with somewhat different characteristics in the northern and southern parts of the basin. The pinnacles of the northern trend occur at depths of 4000 - 7000 feet, are up to 700 feet thick, and average about 100 acres in area. The southern pinnacles occur at depths of 2000 - 3000 feet, are shorter, about 300 feet, and attain larger areas.