New floras of the Libkovice Member from the Libouš Mine (early Miocene, Most Basin)
Published online: 2021-10-27 Coufal, P. – Mejstříková, L. (1996): Unikátní barium-stronciová
mineralizace na lokalitách DNT. – Hnědé Uhlí 1/96, 41–50. Kvaček, Z. – Bůžek, Č. (1983): Třetihorní rostlinná společenstva
severočeské hnědouhelné pánve ve vztahu k litofaciálnímu vývoji.
– 46 str. MS výzk. zpráva, Úst. geol. a geotech. ČSAV,
Ústř. úst. geol. Praha. Kvaček, Z. – Dvořák – Z., Mach, K. – Sakala, J. (2019): Třetihorní rostliny severočeské hnědouhelné pánve. – 192 str. Bílinská
přírodověd. spol., z. s., Granit. Bílina, Praha. Mach, K. – Rappr ich, V. – Faměra, M. – Havelcová, M. – Matys
Grygar, T. – Novotný, T. – Řehoř, M. – Erb an Kocherg ina, Y. V.
(2021): Crandallite-rich beds of the Libkovice Member, Most
Basin, Czech Republic: climatic extremes or paleogeographic
changes at the onset of the Miocene Climatic Optimum?
(v tisku) Mai, D. H. (1995): Tertiäre Vegetationsgeschichte Europas. – 691 str.
G. Fischer. Jena. Matys Grygar, T. – Mach, K. (2013): Regional chemostratigraphic
key horizons in the macrofossil-barren siliciclastic
lower Miocene lacustrine sediments (Most Basin, Eger Graben,
Czech Republic). – Bull. Geosci. 88, 3, 557–571. Matys Grygar, T. – Mach, K. – Koubová, M. – Martinez, M. –
Hron, K. – Fačevicová, K. (2021): Beginning of the Miocene
Climatic Optimum in Central Europe in sediment archive of
the Most Basin, Czech Republic. – Bull. Geosci. 96, 1, 61–81. Matys Grygar, T. – Hošek, M. – Mach, K. – Schnabl, P. –
Martinez, M. (2017): Climatic instability before the Miocene
Climatic Optimum reflected in a Central European lacustrine
record from the Most Basin in the Czech Republic. –
Palaeogeogr., Palaeoclimatol., Palaeoecol. 485, 930–945. Mikuláš, R. – Mach, K. – Dvořák, Z. (2003): Bioturbation
of claystones of the Most Basin in the Bílina quarry
(Miocene, Czech Republic). – Acta Univ. Carol., Geol. 47, 1–4,
79–85. Prokop, J. – Pecharová, M. – Nel, A. (2016): New Cenozoic
dragonflies from the Most Basin and Středohoří Complex
volcanic area (Czech Republic, Germany). – J. nat. Hist. 50,
37–38, 2311–2326. Teodoridis, V. – Kovar-Eder, J. – Mazouch, P. (2011): The IPRvegetation
analysis applied to modern vegetation in SE China
and Japan. – Palaios 26, 10, 623–638. Teodoridis, V. – Kvaček, Z. (2006): Palaeobotanical research
of the Early Miocene deposits overlying the main coal seam
(Libkovice and Lom Members) in the Most Basin (Czech
Republic). – Bull. Geosci. 81, 2, 93–113. Teodoridis, V. – Kvaček, Z. (2015): Palaeoenvironmental
evaluation of Cainozoic plant assemblages from the Bohemian
Massif (Czech Republic) and adjacent Germany. – Bull. Geosci.
90, 3, 695–720. Teodoridis, V. – Mazouch, P. – Kovar-Eder, J. (2021): On-line
application of Drudge 1 and 2 – simple and quick determination
of the modern vegetation most closely resembling fossil plant
assemblages – Neu. Jb. Geol. Paläont., Abh. 299, 1, 71–75.Abstract
Three new early Miocene fossiliferous horizons were
found in the Libouš Mine near Chomutov in the Most Basin.
The Libkovice Member of the Most Formation was originally
considered as devoid of fossils, apart from rare findings in drillcores.
The new fossiliferous horizons within lacustrine clay sediments
can be precisely dated (17.0–17.3 Ma) thanks to their position
close to the phosphate-bearing horizons C1–C3 (Fig. 2, 3), which
allow a broad correlation across the Most Basin (Fig. 1). Newly
recognized floras are characterized by common early Miocene
representatives of Betulaceae, Myricaceae, Ulmaceae, Aceraceae,
Rhamnaceae, Cupresaceae and Pinaceae known from the Most
Basin, with possible indication of a warming trend towards the
upper fossiliferous/crandallite horizon documented by the presence
of thermophilic elements such as Cedrelospermum sp., Bumelia
oreadum and Leguminosae gen. et. sp. indet (Fig. 4). This possible
warming trend in the upper part of the Libkovice Member represents
the beginning of the Middle Miocene Climatic Optimum, which
was confirmed by previous researches. The vegetation analysis
distinguished several plant assemblages of azonal riparian forest,
mixed swamp forest, and zonal mesophytic evergreen broadleaved
forest mixed with pine stands. The results of the Integrated
Plant Record vegetation analysis demonstrate, that the vegetation
corresponds to the Mixed Mesophytic Forest vegetation type with
a close affinity to the living plant assemblage of Fagus crenata
growing on Mt. Fuji in Japan.References