Results of exploratory drilling in Michigan during 1947 were considerably more favorable than during 1946. Of the 263 wildcats drilled, 20 were completed as producing wells, resulting in the discovery of 10 oil fields and 4 gas fields and in the extension of 5 oil fields and 1 gas field. The Kimball Lake field, Newaygo County, Mount Forest field, Bay County, and Stony Lake field, Oceana County, developed new oil reserves. The new gas fields were not of significant size.

Permits to drill 886 wells were issued during 1947, an increase of 164 over 1946. In all, 896 wells were completed compared with 823 completed in 1946. Of these completions, 36 per cent (318) were oil wells, 21 per cent (191) were gas wells, and 43 per cent (387) were dry holes. The average initial potential of the oil wells was 406 barrels per well. The average initial potential of the gas wells was 6,368,586 cubic feet per well. The total footage drilled during the year was 1,990,880 feet, approximately 5 per cent more than in 1946. Wildcat footage was 623,499 feet, an increase of approximately 2½ per cent.

Oil production during 1947 declined to a 5-year low of 16,215,613 barrels. Gas production increased to a new high of 23,954,925,000 cubic feet.

Core drilling continued to be the most satisfactory method of exploration. Permits were issued for 289 geological tests, an increase of 103 over 1946. Two hundred thirty-eight of these were issued for the West Michigan district, the most active in Michigan during 1947. The most significant oil discovery during 1947, the Kimball Lake field, Newaygo County, was the result of core-drill exploration. Little or no seismograph work was done.

The outstanding deep test of the year was the Ohio Oil Company and Pure Oil Company's Reinhardt well No. 1 in the West Branch field, Ogemaw County. It was commenced in February and at the end of 1947 was drilling at approximately 10,600 feet with no substantial showings of oil or gas.