. "Prachovec"@cs . . "prachovcovou"@cs . . . . . . "2148"^^ . . . "siltovec"@cs . . "SiltstoneUSGOV.jpg"@cs . . . "Prachovec"@cs . . "30"^^ . . . . . "Prachovec"@cs . . . . . "prachovcov\u00E9"@cs . . . . . . . . . "r\u016Fzn\u00E1"@cs . . . "zrnit\u00E1"@cs . . "223907"^^ . . . "tufitick\u00E9 siltovce"@cs . . "prachovcov\u00FDmi"@cs . . "Prachovce"@cs . . . . "Prachovec je sediment\u00E1rn\u00ED hornina, zpevn\u011Bn\u00FD ekvivalent prachu, p\u0159i\u010Dem\u017E \u010D\u00E1stice velikosti prachu se na slo\u017Een\u00ED horniny pod\u00EDlej\u00ED minim\u00E1ln\u011B dv\u011Bma t\u0159etinami. V opa\u010Dn\u00E9m p\u0159\u00EDpad\u011B se takov\u00E9 horniny naz\u00FDvaj\u00ED kalovce (2/3 a\u017E 1/3 prachov\u00FDch \u010D\u00E1stic), nebo j\u00EDlovce (m\u00E9n\u011B ne\u017E 1/3 prachov\u00FDch \u010D\u00E1stic z cel\u00E9ho objemu horniny). Vyskytuj\u00ED se ve v\u0161ech sediment\u00E1rn\u00EDch oblastech (od vysokohorsk\u00FDch jezer a\u017E po mo\u0159sk\u00E9 p\u0159\u00EDkopy), v r\u016Fzn\u00FDch klimatick\u00FDch podm\u00EDnk\u00E1ch (od pol\u00E1rn\u00EDch oblast\u00ED po d\u017Eungle) a ve v\u0161ech geologick\u00FDch obdob\u00EDch (od archaika a\u017E po sou\u010Dasnost). Metamorf\u00F3zou prachovc\u016F vznikaj\u00ED b\u0159idlice, s pokra\u010Duj\u00EDc\u00EDm stupn\u011Bm p\u0159em\u011Bny se tvo\u0159\u00ED fylity.D\u016Fle\u017Eit\u00FDm identifika\u010Dn\u00EDm znakem prachov\u00FDch hornin je jejich barva, kter\u00E1 z\u00E1vis\u00ED hlavn\u011B na oxida\u010Dn\u00EDm stupni \u017Eeleza. \u010Cerven\u00E1 a\u017E fialov\u00E1 barva indikuje v\u00FDskyt \u017Eelezit\u00FDch (Fe3+) kationt\u016F, zelen\u00E9 odst\u00EDny naopak \u017Eeleznat\u00E9 (Fe2+) kationty. V\u0161eobecn\u011B se v\u00FDskyt \u017Eelezit\u00FDch kationt\u016F v\u00E1\u017Ee na kontinent\u00E1ln\u00ED (terestrick\u00E1) prost\u0159ed\u00ED, \u017Eeleznat\u00E9 kationty se vyskytuj\u00ED v mo\u0159sk\u00FDch prost\u0159ed\u00EDch.Nej\u010Dast\u011Bji je textura prachovc\u016F vrstevnat\u00E1, ale vyskytuj\u00ED se i mas\u00EDvn\u00ED textury (hlavn\u011B p\u0159i sedimentaci z hust\u00FDch proud\u016F). V jemnozrnn\u00FDch sedimentech se \u010Dasto vyskytuj\u00ED konkrece (kalcitov\u00E9, sideritov\u00E9, pyritov\u00E9, k\u0159emit\u00E9 a fosf\u00E1tov\u00E9), ty vznikaj\u00ED bu\u010F t\u011Bsn\u011B po ulo\u017Een\u00ED, nebo pozd\u011Bji, p\u0159i litifikaci."@cs . "prachovc\u016F"@cs . . "prachovce"@cs . . "15893027"^^ . . "prachovci"@cs . "prachovec"@cs . "Prachovec je sediment\u00E1rn\u00ED hornina, zpevn\u011Bn\u00FD ekvivalent prachu, p\u0159i\u010Dem\u017E \u010D\u00E1stice velikosti prachu se na slo\u017Een\u00ED horniny pod\u00EDlej\u00ED minim\u00E1ln\u011B dv\u011Bma t\u0159etinami. V opa\u010Dn\u00E9m p\u0159\u00EDpad\u011B se takov\u00E9 horniny naz\u00FDvaj\u00ED kalovce (2/3 a\u017E 1/3 prachov\u00FDch \u010D\u00E1stic), nebo j\u00EDlovce (m\u00E9n\u011B ne\u017E 1/3 prachov\u00FDch \u010D\u00E1stic z cel\u00E9ho objemu horniny)."@cs . "prachovc\u00EDch"@cs .