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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.
Microbialite is a benthic sedimentary deposit made of carbonate mud (particle diameter less than 5 μm) that is formed with the mediation of microbes. The constituent carbonate mud is a type of automicrite (or authigenic carbonate mud ); therefore, it precipitates in situ instead of being transported and deposited.
Both of these formations are predominantly igneous rock; the sedimentary rock has been metamorphosed. However, it is still possible to find microfossils in chert, a type of evaporite that forms in sedimentary environments. From the evidence in these rocks, it is likely that early life existed in the form of microbial mats and stromatolites.
Chert varies greatly in color, from white to black, but is most often found as gray, brown, grayish brown and light green to rusty red [9] [10] and occasionally as dark green. [11] Its color is an expression of trace elements present in the rock. Both red and green are most often related to traces of iron in its oxidized and reduced forms ...
Art: marble, although a metamorphosed limestone, is an example of the use of sedimentary rocks in the pursuit of aesthetics and art Architectural uses: stone derived from sedimentary rocks is used for dimension stone and in architecture , notably slate (metamorphosed shale ) for roofing , sandstone for load-bearing buttresses
Both organisms are visible in the sedimentary rock record. For example, in the Galice Formation in Oregon the hemipelagic sequence was composed of slaty radiolarian argillite with radiolarian chert present as well. [7] [8] The argillite in the Galice Formation was composed of radiolarians, terrigenous and tuffaceous detritus, and hydrothermal ...
Coquina (/ k oʊ ˈ k iː n ə /) is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically sorted fragments of mollusks, trilobites, brachiopods, or other invertebrates. [1] [2] The term coquina comes from the Spanish word for "cockle" and "shellfish". [3] [4]
Little is known about the history of the oldest exposed rocks in the area due to extensive metamorphism.This somber, gray, almost featureless crystalline complex is composed of originally sedimentary and igneous rocks with large quantities of quartz and feldspar mixed in. [1] The original rocks were transformed to contorted schist and gneiss, making their original parentage almost unrecognizable.