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St. Louis Limestone
The St. Louis Limestone is a large geologic formation covering a wide area of the midwest of the United States. It is named after an exposure at St. Louis, Missouri. It consists of sedimentary limestone with scattered chert beds, including the heavily chertified Lost River Chert Bed in the Horse Cave Member. It is exposed at the surface through western Kentucky and Middle Tennessee, including the city of Clarksville, Tennessee. The limestone deposit is Mississippian (geologic period), Mississippian in age, in the Meramecian series, roughly 330-340 million years old. Fossils commonly found in the St. Louis include the rugosan corals ''Lithostrotion'' and ''Lithostrotionella'' and the bryozoan ''Fenestrellina''. See also *List of types of limestone References Limestone formations of the United States Mississippian United States Carboniferous Kentucky Mississippian Missouri Carboniferous geology of Virginia Carboniferous Tennessee Mississippian Illinois Carboniferous so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippian (geology)
The Mississippian ( ), also known as Lower Carboniferous or Early Carboniferous, is a subperiod in the geologic timescale or a subsystem of the geologic record. It is the earlier of two subperiods of the Carboniferous period lasting from roughly 358.9 to 323.2 million years ago. As with most other geochronologic units, the rock beds that define the Mississippian are well identified, but the exact start and end dates are uncertain by a few million years. The Mississippian is so named because rocks with this age are exposed in the Mississippi Valley. The Mississippian was a period of marine transgression in the Northern Hemisphere: the sea level was so high that only the Fennoscandian Shield and the Laurentian Shield were dry land. The cratons were surrounded by extensive delta systems and lagoons, and carbonate sedimentation on the surrounding continental platforms, covered by shallow seas. In North America, where the interval consists primarily of marine limestones, i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
