Preliminary results of the lithological and geochemical study of Sm-1 core, Ploužnice horizon, Semily Formation, Krkonoše Piedmont Basin
Abstract
New core drilling for stratigraphical, sedimentological and geochemical investigations of mainly lacustrine deposits of the Ploužnice horizon, Stephanian C, were carried out in Krkonoše Piedmont Basin near Ploužnice in 2009. This study is presenting preliminary interpretations of sedimentological and geochemical investigations.
Selected major and trace elements were analysed by portable RFA. Core SM-1 is 81 deep and records nearly complete section of Ploužnice member.
Both lower and upper lacustrine units are presented and interfingered by fluvial/alluvial red bed unit. Lower unit represents deeper lacustrine facies including offshore, nearshore and palustrine facies dominate in upper unit.
Both units are characteristic by frequent lake-level fluctuations. Ploužnice Lake is interpreted as hydrologically closed system with periods of saline water.
Geochemical study point to climate as a major control of lake-level fluctuations.