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  2. 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 ...

  3. Graded bedding - Wikipedia

    en.wikipedia.org/wiki/Graded_bedding

    Bioclastic formations are of organic sources, such as biochemical chert, which forms from siliceous marine organism decay and diagenesis. Organic sedimentation of parent material from decaying plant matter in bogs or swamps can also result in a graded bedding complex. This activity leads to formation of peat or coal, after thousands of years.

  4. Wackestone - Wikipedia

    en.wikipedia.org/wiki/Wackestone

    Fragmented bioclastic wackestone A Wackestone in thin section (width of image is 10 mm). Under the Dunham classification (Dunham, 1962 [1]) system of limestones, a wackestone is defined as a mud-supported carbonate rock that contains greater than 10% grains.

  5. Encrinite - Wikipedia

    en.wikipedia.org/wiki/Encrinite

    Encrinite (crinoidal limestone) from the Mississippian Ft. Payne Formation of southern Kentucky Example encrinite from the Silurian Brassfield Limestone of Ohio. Note different sizes of ossicles present. Encrinites are a type of grain-supported bioclastic sedimentary rock in which all or most of the grains are crinoid ossicles.

  6. Eolianite - Wikipedia

    en.wikipedia.org/wiki/Eolianite

    Eolianite or aeolianite is any rock formed by the lithification of sediment deposited by aeolian processes; that is, the wind. In common use, however, the term refers specifically to the most common form of eolianite: coastal limestone consisting of carbonate sediment of shallow marine biogenic origin, formed into coastal dunes by the wind, and ...

  7. Volcaniclastics - Wikipedia

    en.wikipedia.org/wiki/Volcaniclastics

    The Espinaso Formation includes a wide variety of volcaniclastic materials. Volcaniclastics are geologic materials composed of broken fragments of volcanic rock. [1] These encompass all clastic volcanic materials, regardless of what process fragmented the rock, how it was subsequently transported, what environment it was deposited in, or whether nonvolcanic material is mingled with the ...

  8. Calcarenite - Wikipedia

    en.wikipedia.org/wiki/Calcarenite

    The Pietra di Bismantova in the northern Apennine (Emilia Romagna region, northern Italy) is an example of calcarenite formation.. 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.

  9. 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.