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  2. Sandstone - Wikipedia

    en.wikipedia.org/wiki/Sandstone

    Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks. [1] Most sandstone is composed of quartz or feldspar, because they are the most resistant minerals to the weathering processes at the Earth's ...

  3. Sedimentology - Wikipedia

    en.wikipedia.org/wiki/Sedimentology

    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; Ceramics and industrial materials: clay for pottery and ceramics including bricks; cement and lime derived from limestone.

  4. 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.

  5. Stonehenge's central rock originated in Scotland, a new study ...

    www.aol.com/news/stonehenges-central-rock-came...

    The ancient monument’s “altar stone,” a sandstone rock at its center, likely originated in present-day Scotland, according to a study published Wednesday in the journal Nature.

  6. Clastic rock - Wikipedia

    en.wikipedia.org/wiki/Clastic_rock

    The two major types are silicate based and carbonate based. The majority of silica cements are composed of quartz, but can include chert, opal, feldspars and zeolites. [3] Composition includes the chemical and mineralogic make-up of the single or varied fragments and the cementing material holding the clasts together as a rock. These ...

  7. Concretion - Wikipedia

    en.wikipedia.org/wiki/Concretion

    However, the evidence is ambiguous, and many or most concretions may have formed by pervasive cementation of the entire volume of the concretion at the same time. [ 43 ] [ 44 ] [ 38 ] For example, if the porosity after early cementation varies across the concretion, then later cementation filling this porosity would produce compositional zoning ...

  8. Franciscan Complex - Wikipedia

    en.wikipedia.org/wiki/Franciscan_Complex

    The most abundant fossils by far are microfossils, particularly in the cherts, which contain single-celled organisms called radiolarians that have exoskeletons of silica. There are also in some of the shales microfossils of planktonic foraminifera that have exoskeletons of carbonate .

  9. Liesegang rings (geology) - Wikipedia

    en.wikipedia.org/wiki/Liesegang_rings_(geology)

    Liesegang rings usually cut across layers of stratification and occur in many types of rock, some of which more commonly include sandstone and chert. [3] Though there is a high occurrence of Liesegang rings in sedimentary rocks, [6] relatively few scientists have studied their mineralogy and texture in enough detail to write more about them. [12]