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Fossiliferous limestone is a type of limestone that contains noticeable quantities of fossils or fossil traces. If a particular type of fossil dominates, a more specialized term can be used as in "Crinoidal", "Coralline", "Conchoidal" limestone. If seashells, shell fragments, and shell sand form a significant part of the rock, a term "shell ...
A diagram of various depositional environments. In geology, depositional environment or sedimentary environment describes the combination of physical, chemical, and biological processes associated with the deposition of a particular type of sediment and, therefore, the rock types that will be formed after lithification, if the sediment is preserved in the rock record.
A well-cemented coquina is classified as a biosparite (fossiliferous limestone) according to the Folk classification of sedimentary rocks. [ 6 ] Coquinas accumulate in high-energy marine and lacustrine environments where currents and waves result in the vigorous winnowing, abrasion, fracturing, and sorting of the shells that compose them.
The Columbus Limestone contains brachiopods, trilobites, bryozoans, mollusks, corals, stromatoporoids and echinoderms (including crinoids). Due to their mid-continent depositional environment, the fossils are almost free of deformation caused by tectonic activity common in the Appalachian Mountains .
Shelly limestone is a highly fossiliferous limestone, composed of a number of fossilized organisms such as brachiopods, bryozoans, crinoids, sponges, corals and mollusks. It varies in color, texture and hardness. Coquina is a poorly indurated form of shelly limestone. Shelly limestone is a sedimentary rock because it is made up of fragments.
The massive member is affected by important thickness variations (its total thickness normally can vary from 5–12 m, sometimes even reaching 15 m), caused either by tectonic disturbances or by post-depositional erosion (for instance, in the Mareuil Anticline, the upper Angoumian discordantly overlies the lower Angoumian, occasionally even ...
The depositional environment of the Kope was shallow marine. The central North American continent was a tropical epeiric sea at the time. Jennette and Pryor (1993) interpret the Kope, along with the Bellevue and Fairview Formations, as a progradational succession on a carbonate ramp. The Kope is the most distal facies of the ramp complex.
The formation is composed of 14 facies, grouped into 4 facies associations, named A through D, corresponding to the specific depositional environments. Facies association A, composed mostly of dark grey shales, was deposited on a shelf , shallow enough to be affected by storms, that resulted in sandstone and bioclastic limestone layers.