Dubuque Formation
From Wikipedia, the free encyclopedia
Geologic formation in the United States
| Dubuque Formation | |
|---|---|
| Stratigraphic range: Ordovician | |
| Type | Formation |
| Underlies | Maquoketa Formation |
| Overlies | Galena Group |
| Location | |
| Region | Illinois, Minnesota |
| Country | United States |
The Dubuque Formation is a geologic formation in Illinois, Iowa, Wisconsin and Minnesota. It preserves fossils dating back to the Ordovician period.[1] It comprises carbonate and argillaceous rocks that are between 35 and 45 feet deep.[2]
References
- ↑ Burr, J. H., Jr.; Swain, F. M. (1965). Ostracoda of the Dubuque and Maquoketa Formations of Minnesota and Northern Iowa. Minneapolis: University Of Minnesota. p. 1-3.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ↑ Levorson, C.; Gerk, A.; Broadhead, Thomas (1 January 1979). "Stratigraphy of the Dubuque Formation (Upper Ordovician) in Iowa". Proceedings of the Iowa Academy of Science. 86 (2): 57–65. ISSN 0085-2236. Retrieved 11 June 2025.
| Ph |
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Ph |
| ||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| pЄ |
| ||||||||||||||||||||||||||||||||||||||||||
 | This article about a specific stratigraphic formation in Illinois is a stub. You can help Wikipedia by expanding it. |