Paleontology and geology
During Early Ordovician time, Iowa stood at the edge of a warm, shallow sea. Interplay between this sea and its coastline resulted in alternating deposits of carbonates and sandstones. Algal remains are common fossils from this time interval. The sea retreated briefly, and then advanced to the north, well past Iowa. Hence, depositional environments in Iowa became successively deeper. The limy sediments deposited in this sea became the limestones and carbonates now exposed in the northeastern part of the state. The sea hosted a diverse and luxuriant marine fauna, including algae, clams, snails, nautiloid cephalopods, corals, trilobites, and bryozoans. The rock units also contain thin, but widespread, bentonites (altered volcanic ash beds), indicating volcanic activity somewhere in the region. By the end of Ordovician time, the seas had retreated from Iowa.
Research and Collections | Resources
Research and Collections
Researchers (showing 2 of 2 listings)
University of Iowa Paleontology Repository: The UI Paleontology Repository is home to over a million fossils from all over the world and from all time periods, and is used for research and teaching. We also provide education services, hands-on tours around the collections and geology exhibits for schools and community groups, and fossil identification and collection care services.
Dr. Thomas W. Kammer: Specialty: Evolutionary paleoecology of Paleozoic crinoids, plus lithostratigraphy, biostratigraphy, and sequence stratigraphy of marine Mississippian rocks in the east-central United States. Field areas include West Virginia, Kentucky, Indiana, Illinois, Missouri, and Iowa.
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Databases (showing 1 of 1 listings)
Fossils in My Back Yard: Explore a geologic map of Iowa, county by county, to see lists and photos of fossils in the collections of the University of Iowa Paleontology Repository.
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