Alkaline elements in carbonate rocks of the Macocha and Líšeň Formations in the Mokrá quarry (Moravian Karst)
Vol.19,No.1-2(2012)
Abstract
Keywords:
Moravian Karst; alkaline elements; limestones; calciturbidites
Concentrations of alkaline elements (sodium and potassium) were determined by EDX analysis and also by laboratory gamma–ray spectrometry (in case of potassium) in carbonate rocks of Macocha Fm. and Líšeň Fm. (limestones and calciturbidites) exploited in the Mokrá quarry in the southern part of the Moravian Karst. Platform carbonates of the Macocha Fm. and deep–subtidal to basin–floor nodular limestones of the Líšeň Fm. (so-called Křtiny Lmst.) have only low concentrations of sodium and potassium (in most of samples less than 0.5 wt. % Na2O and less than 0.5 wt. % K2O). The concentrations of alkaline elements in calciturbidites of the Líšeň Fm. in the Moravian Karst are higher: siliciclastic beds of calciturbidites contain 0.6–3.4 wt. % K2O and 0.04–1.8 wt. % Na2O. Increased potassium concentrations in calciturbidites are linked to a presence of phyllosilicates (illite) in siliciclastic beds. Sodium concentrations in siliciclastic beds could be linked to authigenic albite that was identifi ed by electron micro probe analysis.
Moravian Karst; alkaline elements; limestones; calciturbidites
References
Breitenbücher, R. (2006): Alkali–Kieselsäure-Reaktion (AKR) – Folgerungen für den Betonstraßenbau. – Strasse + Autobahn, 4, 205–209, Kirschbaum Verlag, Bonn.
Modrý, S. (2002): Vyloučení alkalické reakce kameniva v betonu na stavbách pozemních komunikací. – MS, ČVUT Praha.