Editing Michigan (section)

===Geology===

The geological formation of the state is greatly varied, with the [[Michigan Basin]] being the most major formation. Primary boulders are found over the entire surface of the Upper Peninsula (being principally of primitive origin), while Secondary deposits cover the entire Lower Peninsula. The Upper Peninsula exhibits Lower [[Silurian]] sandstones, limestones, copper and iron bearing rocks, corresponding to the Huronian system of [[Canada]]. The central portion of the Lower Peninsula contains coal measures and rocks of the [[Pennsylvanian (geology)|Pennsylvanian]] period. [[Devonian]] and sub-Carboniferous deposits are scattered over the entire state.

Michigan rarely experiences [[earthquake]]s, and those that it does experience are generally smaller ones that do not cause significant damage. A 4.6-magnitude earthquake struck in August 1947. More recently, a 4.2-magnitude earthquake occurred on Saturday, May 2, 2015, shortly after noon, about five miles south of [[Galesburg, Michigan]] (9 miles southeast of [[Kalamazoo]]) in central Michigan, about 140 miles west of Detroit, according to the Colorado-based [[U.S. Geological Survey]]'s [[National Earthquake Information Center]]. No major damage or injuries were reported, according to then-Governor [[Rick Snyder]]'s office.<ref>{{cite web |url = http://www.freep.com/story/news/local/2015/05/02/michigan-earthquake/26773069/ |title = No injuries reported after earthquake rattles Michigan |access-date = May 3, 2015 |archive-url = https://web.archive.org/web/20150503111513/http://www.freep.com/story/news/local/2015/05/02/michigan-earthquake/26773069/ |archive-date = May 3, 2015 |url-status = live}}</ref>