Zbiorowiska roślinności węglotwórczej liasowego węgla brunatnego z Poręby koło Zawiercia

Abstract

Histogram sporowo-pyłkowy węglonośnego odcinka warstw blanowickich przeanalizowany został w powiązaniu z budową petrograficzną pokładu węgla. Na tej podstawie zostały scharakteryzowane przypuszczalne zbiorowiska dolnojurajskiej roślinności węglotwórczej i ich sukcesja w procesie antrakogenezy.

VEGETATION ASSEMBLAGES FORMING LIAS BROWN COALS IN THE PORĘBA AREA NEAR ZAWIERCIE Coal-bearing Lower Jurassic strata (Blanowice Beds) are distributed in area between Częstochowa, Dębnik, Siewierz and Olkusz in the Silesian - Cracow Monocline. The coals were mined there in the years 1818-1959. The interest in coal resources connected with small deposits has recently increased, leading to recommence of petrological studies on the deposits, including those of the Blanowice coals. The latter coals were recently shown to represent hard brown coals of the luster variety (l. Kołcon, M. Wagner, 1982). The paper presents the results of palynological studies, connected. with the above mentioned and supplementing them by some data on origin of the coals. The studies covered coaI-bearing part of the section of the Blanowicc Beds. exposed at Kierszuła near Poręba. The analysis of histogram, aimed at identification of coal-forming vegetational assemblages, was carried out with reference to petrographic characteristics of coal layers. The identified spore-pollen assemblage comprises higher cryptogamic plants (Bryopsida, Selaginellopsida, Sphenopsida, Lycopsida, Pteropsida) and the gymnospermous (Pteridospermopsida, Cycadopsida, Bennettitopsida, Ginkgopsida, Coniferopsida). Pollen of coniferous plants (Conferopsida), regarded as connected with the Cheirolepidaceae group,common here but the share of various morphological types of sporangia of the thin-sporangium ferns (Leptofilicidae) is also significant in the studied spectra.

Clarain clearly predominates in the Blanowice coals. An assemblage of herbaceous peat-bog vegetation, characterized by predominance of ferns, was most probably the parent material for that variety of coals. The presence of fairly thick laminae of vitrain in the studied layer indicates some phases with share of forest assemblage marked in area of contemporary peat-bog. The predominance of pollen of coniferous plants in an the analysed spectra does not show coal-forming role of that group of plants as it may be explained by mainly allochtoneous nature of the pollen.