Arenite

Arenite

Arenite (Latin "Arena", sand) is a sedimentary clastic rock with sand grain size between 0.063 mm (0.00256 in) and 2 mm (0.08 in) and contain less than 15% matrix. [ [http://www.britannica.com/eb/article-9009339/arenite Britannica definition of "arenite"] . Accessed on January 1, 2008] The related adjective is "arenaceous". The equivalent Greek-derived term is Psammite, though this is more commonly used for metamorphosed sediments.

Since it refers to grain size rather than chemical composition, the term is used for example in the classification of clastic carbonatic limestones, as the granulometrically equivalent term sandstone is not appropriate for limestone. Other arenites include sandstones, arkoses, greensands and greywackes.

Arenites mainly form by erosion of other rocks or turbiditic re-deposition of sands. Some arenites contain a varying amount of carbonatic components and thus belong to the rock-category of carbonatic sandstones or silicatic limestones. Arenites often appear as massive or bedded medium-grained rocks with a medium- to wide-spaced preferred foliation and often develop a pronounced cleavage.

Pettijohn [Pettijohn F.J. (1975), "Sedimentary Rocks", Harper & Row, ISBN 0-96-045191-2] gives the following descriptive terms based on grain size, avoiding the use of terms such as "clay" or "argillaceous" which carry an implication of chemical composition:

References


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Look at other dictionaries:

  • Arenite — Arénite L arénite est une roche sédimentaire détritique meuble ou consolidée dont les éléments ont une largeur comprise entre 1/16 mm et 2 mm. Le terme est utilisé plutôt à la classification des calcaires détritiques, où le terme équivalent sable …   Wikipédia en Français

  • arénite — ● arénite nom féminin Roche détritique, dont la majorité des grains est comprise entre 2 mm et 64 μm …   Encyclopédie Universelle

  • arenite — [ar′ə nīt΄, er′ə nīt΄] n. [L arena, sand, ARENA + ITE1] sandstone or other sedimentary rock made up chiefly of sand grains …   English World dictionary

  • arenite — /ar euh nuyt , euh ree /, n. Geol. psammite. [ < L (h)aren(a) sand + ITE1] * * * ▪ rock       any sedimentary rock that consists of sand sized particles (0.06–2 millimetres [0.0024–0.08 inch] in diameter), irrespective of composition. More formal …   Universalium

  • Arénite — L arénite est une roche sédimentaire détritique meuble ou consolidée dont les éléments ont une largeur comprise entre 1/16 mm et 2 mm. Le terme est utilisé plutôt à la classification des calcaires détritiques, où le terme équivalent sable est un… …   Wikipédia en Français

  • arenite — ar·e·nite …   English syllables

  • arenite — …   Useful english dictionary

  • lithic arenite — ▪ mineral       sandstone (i.e., sedimentary rock composed of grains 0.06–2 mm [0.0024–0.08 inch] in diameter) containing over 50 percent rock fragments. Lithic arenites most often are of gray or salt and pepper colour because of the inclusion of …   Universalium

  • quartz arenite —       variety of the rock quartzite (q.v.) formed by deposition of silica in subterranean sandstone. * * * …   Universalium

  • sedimentary rock — Rock formed at or near the Earth s surface by the accumulation and lithification of fragments of preexisting rocks or by precipitation from solution at normal surface temperatures. Sedimentary rocks can be formed only where sediments are… …   Universalium

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