Petoskey is a city in the U.S. state of Michigan. It is the county seat of Emmet County, and is the largest settlement within the county. Petoskey has a population of 5,877 at the 2020 census, up from 5,670 at the 2010 census.
A Petoskey stone is a rock and a fossil, often pebble-shaped, that is composed of a fossilized rugose coral, Hexagonaria percarinata. Such stones were formed as a result of glaciation, in which sheets of ice plucked stones from the bedrock, grinding off their rough edges and depositing them in the northwestern portion of Michigan's lower peninsula. In those same areas of Michigan, complete fossilized coral colony heads can be found in the source rocks for the Petoskey stones.
The geology of Illinois includes extensive deposits of marine sedimentary rocks from the Palaeozoic, as well as relatively minor contributions from the Mesozoic and Cenozoic. Ice age glaciation left a wealth of glacial topographic features throughout the state.
The Marcellus Formation or the Marcellus Shale is a Middle Devonian age unit of sedimentary rock found in eastern North America. Named for a distinctive outcrop near the village of Marcellus, New York, in the United States, it extends throughout much of the Appalachian Basin.
Hexagonaria is a genus of colonial rugose coral. Fossils are found in rock formations dating to the Devonian period, about 350 million years ago. Specimens of Hexagonaria can be found in most of the rock formations of the Traverse Group in Michigan. Fossils of this genus form Petoskey stones, the state stone of Michigan. They can be seen and found in most Midwestern U.S. states.
The Devonian Jeffersonville Limestone is a mapped bedrock unit in Indiana and Kentucky. It is highly fossiliferous.
Paleontology in Michigan refers to paleontological research occurring within or conducted by people from the U.S. state of Michigan. During the Precambrian, the Upper Peninsula was home to filamentous algae. The remains it left behind are among the oldest known fossils in the world. During the early part of the Paleozoic Michigan was covered by a shallow tropical sea which was home to a rich invertebrate fauna including brachiopods, corals, crinoids, and trilobites. Primitive armored fishes and sharks were also present. Swamps covered the state during the Carboniferous. There are little to no sedimentary deposits in the state for an interval spanning from the Permian to the end of the Neogene. Deposition resumed as glaciers transformed the state's landscape during the Pleistocene. Michigan was home to large mammals like mammoths and mastodons at that time. The Holocene American mastodon, Mammut americanum, is the Michigan state fossil. The Petoskey stone, which is made of fossil coral, is the state stone of Michigan.
Paleontology in Wisconsin refers to paleontological research occurring within or conducted by people from the U.S. state of Wisconsin. The state has fossils from the Precambrian, much of the Paleozoic, some a parts of the Mesozoic and the later part of the Cenozoic. Most of the Paleozoic rocks are marine in origin. Because of the thick blanket of Pleistocene glacial sediment that covers the rock strata in most of the state, Wisconsin’s fossil record is relatively sparse. In spite of this, certain Wisconsin paleontological occurrences provide exceptional insights concerning the history and diversity of life on Earth.
The Four Mile Dam Formation, also called the Four Mile Dam Limestone, is a geologic formation in Michigan. It preserves fossils dating back to the middle Devonian period.
The Gravel Point Formation is a geologic formation in western Michigan. It preserves fossils dating back to the middle Devonian period and correlates with the Long Lake Limestone and Alpena Limestone.
The Norway Point Formation is a geologic formation in Michigan. It preserves fossils dating back to the middle Devonian period.
The Thunder Bay Limestone is a geologic formation in Michigan. It preserves fossils dating back to the Devonian 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 Welden Limestone is a geologic formation in Oklahoma. It preserves fossils dating back to the Carboniferous period. It is restricted to the Lawrence Uplift of southern Oklahoma. In this region, the Welden Limestone is the only carbonate unit deposited during the span of time from Late Devonian to the Pennsylvanian.
The Mount Hawk Formation is a stratigraphic unit of Late Devonian age. It is present on the western edge of the Western Canada Sedimentary Basin in the Rocky Mountains and foothills of Alberta. It consists primarily of limestone and mudstone, and was named for Hawk Mountain in Jasper National Park by R. de Wit and D.J. McLaren in 1950.
The Mount Whyte Formation is a stratigraphic unit that is present on the western edge of the Western Canada Sedimentary Basin in the southern Canadian Rockies and the adjacent southwestern Alberta plains. It was deposited during Middle Cambrian time and consists of shale interbedded with other siliciclastic rock types and limestones. It was named for Mount Whyte in Banff National Park by Charles Doolittle Walcott, the discoverer of the Burgess shale fossils, and it includes several genera of fossil trilobites.
The Rockport Quarry Limestone is a geologic formation in Michigan. It preserves fossils dating back to the middle Devonian period.
The Waynesboro Formation is a limestone, dolomite, and sandstone geologic formation in Virginia, Maryland, Pennsylvania and West Virginia. In some areas it is composed of limestone and dolomite. The Waynsboro Formation is one of the formations that make up the Shenandoah Valley. It dates back to the Cambrian period and is not considered fossiliferous.
The Windom shale or Windom member is a member of the Moscow formation in New York. It preserves fossils going back to the Givetian stage of the middle Devonian. The Windom shale is widely known for its high quality trilobite fossils.
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