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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. Coquina - Wikipedia

    en.wikipedia.org/wiki/Coquina

    Overlying the fossiliferous sands and sandy clays of the upper San Fernando River in northeastern Mexico is a bed of coquina limestone dating probably to the Cenozoic era. [17] Coquina deposits also occur in the Baja California peninsula, including submerged "reefs". So-called coquina "reefs" occur at Punta Borrascosa, San Felipe and ...

  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. Calcarenite - Wikipedia

    en.wikipedia.org/wiki/Calcarenite

    Calcarenite is a type of limestone that is composed predominantly, more than 50 percent, of detrital (transported) sand-size (0.0625 to 2 mm in diameter), carbonate grains. The grains consist of sand-size grains of either corals , shells , ooids , intraclasts , pellets , fragments of older limestones and dolomites , other carbonate grains, or ...

  6. 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.

  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. Sedimentary rock - Wikipedia

    en.wikipedia.org/wiki/Sedimentary_rock

    Uluru (Ayers Rock) is a large sandstone formation in Northern Territory, Australia.. Sedimentary rocks can be subdivided into four groups based on the processes responsible for their formation: clastic sedimentary rocks, biochemical (biogenic) sedimentary rocks, chemical sedimentary rocks, and a fourth category for "other" sedimentary rocks formed by impacts, volcanism, and other minor processes.

  9. Micrite - Wikipedia

    en.wikipedia.org/wiki/Micrite

    Micrite is a limestone constituent formed of calcareous particles ranging in diameter up to four μm formed by the recrystallization of lime mud. [1] [2] The term was coined in 1959 by Robert Folk for his carbonate rock classification system. [2] Micrite is derived from MICRocrystalline calcITE.