The Buckeye oil field, located in T. 18 N., R. 1 W., Gladwin County, Michigan, was discovered in 1936, and represents a structural accumulation similar to other pools in the Michigan basin. The field consists of two separate oil pools, quite unlike in their ability to produce oil. Though the two pools are comparable as to size, structure, and age, the north pool had produced by the end of 1939 approximately 13 million barrels of oil as compared with less than 3,400,000 barrels for South Buckeye. This difference in productivity is attributed to a lateral change in the lithology of the producing limestone resulting in decreased porosity and lower permeability. Since a thick mantle of glacial drift masks the surface of the field and a wide area surrounding it, all informatio concerning the two fields has been derived from subsurface studies of drillers' logs and well cuttings. Subsurface maps show the structure to be a northwest-southeast trending, asymmetrical, nearly flat-topped anticline, with maximum dips approaching 200 feet per mile along the southwest flank. Formations drilled are Pennsylvanian, Mississippian, and Devonian in age, while production is from the Devonian Dundee limestone. Producing wells average 3,627 feet in depth. The source of the oil and the origin of the porosity can not be demonstrated but the various lines of reasoning which have been applied in attempts to arrive at the truth concerning these matters are discussed.