Michigan is not usually listed alongside Texas or North Dakota when people talk about oil states, but it has been producing oil and gas for over a century. The state has unique geology that includes both conventional carbonate reef fields and a shallow natural gas shale play. Michigan produces around 15,000 to 20,000 barrels of oil per day and a modest amount of natural gas.
Niagaran Reef Fields
One of Michigan's most distinctive geological features is its Niagaran Reef fields. These are ancient coral reefs that formed roughly 420 million years ago and are now buried deep underground in the central part of the Lower Peninsula. Oil became trapped in the porous carbonate rock of these reefs. The reefs are small but highly productive — a single reef can produce hundreds of thousands of barrels over its lifetime. Exploration for new reef targets is still active today.
The Antrim Shale
The Antrim Shale in northern Michigan is one of the most unusual natural gas plays in the country. Unlike deep shale plays like the Marcellus or Haynesville, the Antrim sits at a relatively shallow depth of only 500 to 2,000 feet. It produces biogenic gas — gas created by bacteria breaking down organic material — rather than the thermogenic gas formed by heat and pressure deep in the earth. Thousands of Antrim wells have been drilled across northern Michigan since the 1980s.
Who Regulates Michigan Wells?
The Michigan Department of Environment, Great Lakes, and Energy (EGLE) — Oil, Gas and Minerals Division is the state regulatory agency. EGLE takes its oversight role seriously given Michigan's proximity to the Great Lakes, the largest freshwater system in the world. Any contamination of groundwater could affect drinking water for millions of people. EGLE requires detailed well construction standards and maintains a public well database at michigan.gov/egle.
Underground Natural Gas Storage
Michigan is also notable for its extensive network of underground natural gas storage fields. Depleted oil and gas reservoirs across the state are used to store natural gas during the summer and withdraw it during winter when demand is high. Michigan has more underground gas storage capacity than almost any other state.