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English: Limestone is a biogenic sedimentary rock composed of the mineral calcite (CaCO3), which bubbles in acid. Many geologically young limestones are composed of aragonite (also CaCO3). Many geologically young limestones are composed of aragonite (also CaCO3).
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.
Siliceous ooze is a type of biogenic pelagic sediment located on the deep ocean floor. Siliceous oozes are the least common of the deep sea sediments, and make up approximately 15% of the ocean floor. [1] Oozes are defined as sediments which contain at least 30% skeletal remains of pelagic microorganisms. [2]
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
The mollusc shell is a biogenic composite material that has been the subject of much interest in materials science because of its unusual properties and its model character for biomineralization. Molluscan shells consist of 95–99% calcium carbonate by weight, while an organic component makes up the remaining 1–5%.
The upper chert member, which is the uppermost member of the Dresser Formation, consists of centimeter-layered white-and-blue to black layered chert. It lacks the heterogeneity of the underlying North Pole chert, remains the same relative thickness along strike, and is not offset by the growth faults that affect the underlying members.