The Traverse Group is a geologic group in Michigan, Indiana and Ohio comprising middle Devonian limestones with calcareous shale components. Its marine fossils notably include Michigan's state stone, the Petoskey stone, among other corals and records of ancient marine life. A range of trilobites has also been found in the Traverse Group.
The Williamsport Sandstone is a sandstone geologic formation in West Virginia, Virginia, Pennsylvania, and Maryland. the formation includes the Cedar Creek Limestone member. Near Cumberland, Maryland it includes the Cedar Creek Limestone member. It preserves fossils dating back to the Silurian period.
The Cuyahoga Formation is a geologic formation in Ohio. The age of the formation is difficult to determine, because of a lack of diagnostic fossils. Roughly, the formation dates from the Late Kinderhookian to the Middle Osagean. Eight members are recognized, among them the Orangeville Shale, Sharpsville Sandstone, and Meadville Shale.
The Golconda Formation is a geologic formation in Kentucky. It preserves fossils dating back to the Carboniferous period. In Indiana, the Golconda, it is called the Golconda Limestone and is part of the Stephensport Group.
The Oranda Formation is a geologic formation in Virginia. It preserves fossils dating back to the Ordovician period.
The Rockdale Run Formation is a geologic formation in Maryland, Pennsylvania, Virginia and West Virginia. It preserves fossils dating back to the Ordovician period.
The Sonyea Group is a geologic group in the northern part of the Appalachian Basin. It preserves fossils dating back to the Devonian period.
The Trenton Group is a geologic unit in Canada and Michigan, Ohio, New York State and Indiana, Pennsylvania, and West Virginia in the United States. It dates back to the Ordovician period.
The Rock Stream Formation is a geologic formation in New York. It preserves fossils dating back to the Devonian 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 Navarro Group is a geologic group in Arkansas, Texas and Coahuila, Mexico. It preserves fossils dating back to the Cretaceous 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 Lehman Formation is a geologic formation in Utah. It preserves fossils dating back to the Ordovician period.
The Wood Canyon Formation is a geologic formation in the northern Mojave Desert of Inyo County, California and Nye County and Clark County, Nevada.
The Merced Formation is a geologic formation in California, and also in Oregon and Washington state. It is named for Lake Merced, a natural lake on the western San Francisco coastline.
The Puget Group is a geologic group in Washington (state). It preserves fossils dating back to the Paleogene period.
The Ponce Limestone is a geologic formation in Puerto Rico. It preserves fossils dating back to the Neogene period (20.45 million years ago.
The Stanford Formation is a geologic formation in England. It preserves fossils dating back to the Oxfordian stage of the Middle Jurassic period, around 160 million years ago.
The Molasse Coquilliere is a geologic formation in France. It preserves fossils dating back to the Neogene period, which started 23.03 million years ago and ended 2.58 million years ago.
The Saginaw Formation is a geologic formation in Michigan. It preserves fossils dating back to the Pennsylvanian period.
Michigan 
United States 
