The Salem Formation is a geologic formation in Illinois, Indiana, Kentucky, and Missouri. It preserves fossils dating back to the Mississippian subperiod.
The Davis Formation is a geologic formation in Indiana and Missouri. It preserves fossils dating back to the Cambrian period.
The Eau Claire Formation is a geologic formation in the north central United States. It preserves trilobite fossils from the Cambrian Period.
The Warsaw Formation is a geologic formation in Illinois, Iowa and Missouri. It preserves fossils dating back to the Mississippian subperiod.
The Roubidoux Formation is a geologic formation in the Ozarks of Missouri and in Virginia. It preserves fossils dating back to the Ordovician period.
The Rome Formation is a geologic formation in Tennessee. It preserves fossils dating back to the Cambrian period.
The Tomstown Dolomite or Tomstown Formation is a geologic formation in Maryland, Pennsylvania, Virginia and West Virginia. It preserves fossils dating to the Cambrian Period.
The Elvins Group is a geologic group in Missouri. It preserves fossils dating back to the Cambrian period.
The Conasauga Formation is a geologic formation in Georgia. It preserves fossils dating back to the Cambrian period.
The Franconia Formation is a geologic formation in the upper mid-western United States, with outcroppings found in Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin. It preserves fossils dating back to the Cambrian period. It was named the Franconia Formation due to the first published documentation of exposures in vicinity of Franconia, Minnesota in the 1897 Ph.D. dissertation by Charles P. Berkley at the University of Minnesota titled Geology of the St. Croix Dalles. The Franconian stratigraphic stage was named after this formation.
The Jordan Sandstone is a geologic formation in Wisconsin. It preserves fossils dating back to the Cambrian period.
The St. Clair Limestone is a geologic formation in Arkansas, Indiana, Missouri, and Oklahoma. It preserves fossils dating back to the Silurian period. This high density, high magnesium dolomitic limestone was originally classified as a marble in Oklahoma due to the fact that it would hold a high polish, hence Marble City.
The Derby-Doerun Dolomite is a Cambrian geologic formation exposed in southeast Missouri. Originally the Derby and Doerun were originally considered separate formations, but now considered a single unit. The combined name is from the Derby Mine and the Doe Run Lead Company of the Old Lead Belt.
The Eminence Formation or Eminence Dolomite is a geologic formation in Missouri. It preserves fossils dating back to the Cambrian period.
The Fern Glen Formation is a geologic formation in eastern and southeastern Missouri. It preserves fossils dating back to the Osagean Series of the Mississippian subperiod.
The Moccasin Springs Formation is a geologic formation in Missouri. It preserves fossils dating back to the Silurian period.
The Bowling Green Dolomite is a geologic formation in Missouri. It preserves fossils dating back to the Silurian period.
The Dotsero Formation is a geologic formation in Colorado. It preserves fossils dating back to the Cambrian period.
The Sawatch Formation is a geologic formation in eastern Colorado. It is a sedimentary sequence formed approximately 530 million years ago during a marine transgression. It preserves fossils dating back to the Cambrian period. It is composed of glauconitic and quartz-rich sandstone.
The Dunderberg Shale is a geologic formation in Nevada and Utah.
