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  2. Marine biogenic calcification - Wikipedia

    en.wikipedia.org/wiki/Marine_biogenic_calcification

    Limestone rock, which consists mostly of calcite, is a prime example of a rich source of calcium to the ocean. The source of the majority of inorganic calcium present in the ocean is due to riverine deposition, though volcanic activity interacting with seawater does provide some calcium as well.

  3. 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 ...

  4. Marine sediment - Wikipedia

    en.wikipedia.org/wiki/Marine_sediment

    Marine sediment, or ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated on the seafloor.These particles either have their origins in soil and rocks and have been transported from the land to the sea, mainly by rivers but also by dust carried by wind and by the flow of glaciers into the sea, or they are biogenic deposits from marine organisms or from ...

  5. Bioclast - Wikipedia

    en.wikipedia.org/wiki/Bioclast

    Limestone of crinoids. Bioclasts are skeletal fossil fragments of once living marine or land organisms that are found in sedimentary rocks laid down in a marine environment—especially limestone varieties around the globe, some of which take on distinct textures and coloration from their predominate bioclasts—that geologists, archaeologists and paleontologists use to date a rock strata to a ...

  6. Chalk - Wikipedia

    en.wikipedia.org/wiki/Chalk

    Chalk is a soft, white, porous, sedimentary carbonate rock.It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor.

  7. Shallow water marine environment - Wikipedia

    en.wikipedia.org/wiki/Shallow_water_marine...

    The most common evaporite minerals found within modern and ancient deposits are gypsum, anhydrite, and halite. These minerals can occur as crystalline layers, isolated crystals, or clusters of crystals. [2] Approximately 75% of surface sediments are in shallow marine environments, holding most Phanerozoic and Precambrian sedimentary rock. [3]

  8. Lime (material) - Wikipedia

    en.wikipedia.org/wiki/Lime_(material)

    In the lime industry, limestone is a general term for rocks that contain 80% or more of calcium or magnesium carbonate, including marble, chalk, oolite, and marl.Further classification is done by composition as high calcium, argillaceous (clayey), silicious, conglomerate, magnesian, dolomite, and other limestones. [5]

  9. Geology of Austria - Wikipedia

    en.wikipedia.org/wiki/Geology_of_Austria

    The famous Halstatt Limestone, well known for ammonite fossils, was deposited in warm shallow water less than 100 meters deep. The Meliatic Superunit, on the other hand, preserves deep sea siliceous material formed 4000 meters below the surface of the Tethys Ocean.