The exploration for and development of Middle Silurian Niagaran reefs dominated Michigan's oil and gas industry activity for the 19th year in a row. In 1987, 48% of the wells drilled had Niagaran objectives. Remaining drilling activity was spread among rocks from the Mississippian to the Precambrian throughout the Michigan basin.

Exploration resulted in 48 new discoveries, 52% of which were Niagaran reef reservoirs. Another 21% of the discoveries was in the still-growing Lower Ordovician deep gas play; an additional 13% of the discoveries was attributed to a rapidly expanding shallow gas play in the Devonian Antrim Shale.

Exploration and development drilled footage was 1,218,472 ft exploratory and 898,575 ft development, compared with 1,496,033 ft exploratory and 1,220,013 ft development in 1986. An additional 38,215 ft was drilled in facility or service wells.

Gas sales declined in 1987, whereas oil production rose slightly. Preliminary figures show that Michigan produced 25,937,363 bbl of oil and 150,308 mmcf of gas in 1987.