The first drilling for oil at Saginaw was in 1912 by the Saginaw Valley Development Company. The wells were located on the south limb of the Saginaw anticline. Oil was found, though not in commercial quantities, in the "Saginaw sand"--a dolomitic lime in the Traverse formation. The discovery well leading to the present development was drilled in the fall of 1925 by the Saginaw Prospecting Company.

Most of the production is from the Berea sand of Mississippian age, at depths ranging from 1,800 to 1,860 feet. Wells, after being shot, produce from two or three barrels to forty barrels a day, depending upon location on structure and "tightness" of sand. The oil is of 46-degree gravity and contains about 48 per cent gasoline.

On June 1, two wells were producing from the Saginaw lime at a depth of 2,300 feet. This lime is in the Traverse formation of Devonian age. Other wells drilled to this "pay," and favorably located, have been dry.

The total production of the field on June 1 was about 1,400 barrels a day from more than 190 wells.

The limit of the field is approximately defined, except at the southeast, where the trend of the pool is into the business district.

It is probable that additional production will be found in the eastern part of the state should conditions structurally favorable be found. The thickness of glacial drift and the absence of the Berea sand in western Michigan make this part of the state less favorable for oil and gas development.