Due to wartime restrictions and the failure of discoveries to locate important pools, oil- and gas-well drilling operations in Michigan during 1942 decreased 28 per cent from 1941, although the footage drilled was only 12 per cent or 240,000 feet less. The "Basin," with two-thirds of the state's completions, continued to be the most active district.

During 1942, twenty-one oil fields and extensions and two gas fields were discovered. The most promising discoveries in the "Basin" district were the Evart, Fork, Prosper, East Norwich, and South Adams fields. In southwestern Michigan, the South Zeeland and North Bangor fields were discovered and partially developed. Oil production was more than 21,750,000 barrels, an increase of 23 per cent over 1941 and only approximately 1,750,000 barrels less than the state's greatest production in 1939.

Gas-well completions decreased during 1942. Activity centered in the development of previously discovered fields in Clare and Osceola counties where two-thirds of the new gas wells were drilled. Gas production increased 18 per cent over 1941, reaching more than 17,700,000,000 cubic feet, a new all-time record.

The discovery of new productive zones in deeper formations opened an entirely new field of development in the state. Commercial production was established from the Detroit River and Sylvania formations (Devonian) in six areas in the "Basin" district. In one area in southwestern Michigan production was found near the Bass Island-Salina contact (Silurian). The age of the producing stratum is not yet determined.

Core-testing activity was greater during 1942 than in any previous year. Approximately 300 tests were drilled principally in the northern and northwestern parts of the Southern Peninsula.