oolite

oolite
oolitic /oh'euh lit"ik/, adj.
/oh"euh luyt'/, n. Geol.
a limestone composed of minute rounded concretions resembling fish roe, in some places altered to ironstone by replacement with iron oxide. Also called egg stone.
[1775-85; ( < F oölithe) < NL oölithes. See OO-, -LITE]

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rock
      ovoid or spherical crystalline deposit with a concentric or radial structure; most are composed of calcium carbonate, but some are composed of silica, siderite, calcium phosphate, iron silicate, or iron oxide. Oölite diameters range from 0.25 to 2 mm (0.01 to 0.08 inch), with most being in the 0.5- to 1-millimetre range; oölitic bodies with diameters greater than 2 mm are called pisolites (pisolite).

      The term oölite has been applied both to the concretionary bodies and to the rock composed largely of such structures; to avoid ambiguity, these structures sometimes have been called oöids, oöliths, or ovulites and the term oölite reserved for the rock. The term also is used in an adjectival sense, such as oölitic limestone or oölitic chert. False oölites bear superficial resemblance to oölites but are devoid of a regular internal structure.

      Calcareous oölites form where cold oceanic waters flow onto warm shallow banks, as in the Bahamas. The carbonate is precipitated on bits of shell, quartz grains, or other nuclei. They also are known to form in springs and caves, as cave pearls.

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  • Oolite — Logo (von Webpage) …   Deutsch Wikipedia

  • Oolite — Скриншот из версии для Mac OS X …   Википедия

  • Oolite — O [ o]*lite, n. [Gr. w, o n an egg + lite: cf. F. o[ o]lithe. So named from its resemblance to the roe of fish.] (Geol.) A variety of limestone, consisting of small round grains, resembling the roe of a fish. It sometimes constitutes extensive… …   The Collaborative International Dictionary of English

  • oolite — (n.) rock consisting of fine grains of carbonate of lime, 1785, from Mod.L. oolites, from oo , comb. form of Gk. oon egg (cognate with O.E. æg, see EGG (Cf. egg) (n.)) + lithos stone. So called because the rock resembles the roe of fish …   Etymology dictionary

  • oolite — [ō′ōlith, ō′əlithō′ō līt΄, ō′əlīt΄] n. [Fr oölithe: see OO & LITE] 1. a tiny, spherical or ellipsoid particle with concentric layers, usually of calcium carbonate, formed in wave agitated sea waters 2. a rock composed chiefly of oolites: Also… …   English World dictionary

  • Oolite — For other uses, see Oolite (disambiguation). Modern ooids from a beach on Joulter s Cay, The Bahamas …   Wikipedia

  • oolite — oolithe [ ɔɔlit ] n. f. ou m. VAR. oolite • 1752 n. f.; de oo et lithe ♦ Minér. Calcaire formé de grains sphériques (comparés à des œufs de poissons). Les oolithes sont caractéristiques du jurassique ancien. Formation analogue de grains d oxyde… …   Encyclopédie Universelle

  • Oolite — Oolithe Oolithes ferrugineuses …   Wikipédia en Français

  • oolite — /ˈoʊəlaɪt/ (say ohuhluyt) noun 1. a small spherical to ellipsoidal concretion, usually calcareous, formed in shallow water under special conditions. 2. a limestone composed of such concretions, in some places altered to ironstone by replacement… …  

  • oolite — oolitinė klintis statusas T sritis chemija apibrėžtis Klintis, susidedanti iš mažų apvalių kalcito grūdelių. atitikmenys: angl. oolite; oolitic limestone rus. оолитовый известняк …   Chemijos terminų aiškinamasis žodynas

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