The Detroit River Group is a
geologic group
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Eart ...
in
Michigan
Michigan () is a state in the Great Lakes region of the upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the 10th-largest state by population, the 11th-largest by area, and the ...
and
Ohio
Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...
. It preserves
fossils
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...
dating back to the
Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...
period
Period may refer to:
Common uses
* Era, a length or span of time
* Full stop (or period), a punctuation mark
Arts, entertainment, and media
* Period (music), a concept in musical composition
* Periodic sentence (or rhetorical period), a concept ...
.
References
*
Further reading
* Brian R. Pratt, ''Lower Devonian Stromatoporoid reefs. Formosa Reef Limestone (Detroit River Group) of Southwestern Ontario.'' In: ''Reefs, Canada and Adjacent Area'', ed. by H.H.J. Geldsetzer, N.P. James and G.E. Tebbutt, Editors Canadian Society of Petroieum Geologists Memoir 13, 1989, p. 506-509
* Gilbert Klapper and, William A. Oliver, Jr., ''The Detroit River Group is Middle Devonian: Discussion on "Early Devonian age of the Detroit River Group, inferred from Arctic stromatoporoids".'' (Canadian Journal of Earth Sciences, 1995, 32(7): 1070–1073, https://doi.org/10.1139/e95-088
Geologic groups of Michigan
{{Michigan-geologic-formation-stub