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  2. Fossiliferous limestone - Wikipedia

    en.wikipedia.org/wiki/Fossiliferous_limestone

    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 ...

  3. Shelly limestone - Wikipedia

    en.wikipedia.org/wiki/Shelly_limestone

    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.

  4. Limestone - Wikipedia

    en.wikipedia.org/wiki/Limestone

    Limestone (calcium carbonate CaCO 3) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO 3. Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place ...

  5. Carboniferous Limestone - Wikipedia

    en.wikipedia.org/wiki/Carboniferous_Limestone

    It was formed in warm, shallow tropical seas teeming with life. The rock is made up of the shells and hard parts of millions of sea creatures, some up to 30 cm in length, encased in carbonate mud. Fossil corals, brachiopods and crinoids are frequently in evidence as components of Carboniferous Limestone; indeed the rock is full of fossils.

  6. Jeffersonville Limestone - Wikipedia

    en.wikipedia.org/wiki/Jeffersonville_Limestone

    The Jeffersonville is a coarse grained, dark gray, thick bedded, fossiliferous limestone. [2] R. D. Perkins (1963) divided the Jeffersonville into five zones based on petrology and fossil content, [4] and these are summarized below (in stratigraphic order): Paraspirifer acuminatus zone (top) fenestrate bryozoan-brachiopod zone; Brevispirifer ...

  7. List of types of limestone - Wikipedia

    en.wikipedia.org/wiki/List_of_types_of_limestone

    Carboniferous LimestoneLimestone deposited during the Dinantian Epoch of the Carboniferous Period; Coquina – Sedimentary rock that is composed mostly of fragments of shells; Coral rag – Limestone composed of ancient coral reef material; Chalk – Soft carbonate rock; Fossiliferous limestoneLimestone containing fossils

  8. Tufa - Wikipedia

    en.wikipedia.org/wiki/Tufa

    Tufa columns at Mono Lake, California. Tufa is a variety of limestone formed when carbonate minerals precipitate out of water in unheated rivers or lakes. Geothermally heated hot springs sometimes produce similar (but less porous) carbonate deposits, which are known as travertine or thermogene travertine.

  9. Fusulinida - Wikipedia

    en.wikipedia.org/wiki/Fusulinida

    Fusulinid limestone, Upper Pennsylvanian; Elk County, Kansas. Field of view is 3.9 cm wide. Link at source to view of entire slab. The Fusulinida is an extinct order within the Foraminifera in which the tests are traditionally considered to have been composed of microgranular calcite. Like all forams, they were single-celled organisms.