The EGSP Michigan No. 1, located in East Central Otsego County, Michigan, lies on the southern flank of Michigan's northern Niagaran pinnacle reef fairway, an area which has undergone considerable drilling activity in the past few years. The well is operated by Wolverine Gas and Oil Company. The site was selected by DOE/METC as part of the resource characterization program of the Antrim Shale of the Michigan Basin. The well was spudded on January 5, 1980 by Cedco Drilling Company. After the 11-3/4-inch O.D. surface string was run and cemented, the well was drilled to 1290 feet, which was selected as the start of the coring task. Gruy Federal, Inc., the prime DOE contractor for the field supervision of the coring activities, assumed responsibility of the well when the coring depth was reached. Using a 7-27/32-inch diamond coring bit and a 60-foot core barrel, Christensen recovered two cores having a total length of 103 feet and accounting for a 100 percent recovery. However, the second coring trip was cut short due to core barrel jamming. Shortly after the total depth of 1394 feet was reached, Schlumberger ran a suite of geophysical logs consisting of compensated density-neutron, sonic dual laterolog, variable density wave form, fracture identification, and spectralog. After logging. the hole was reamed to 11 inches, the rig released, and Gruy's responsibilities terminated.