Klastyczne osady dolnego werfenu (seisu) w Tatrach

Abstract

LOWER WERFENIAN (SEISIAN) CLASTICS IN THE TATRA MTS.The Lower Werfenian (Seislian) clastics in the Tatra Mts. occur within autochtonous and fold, units, also in the lower sub-tatric (Kriżna) nappe units. Within autochtonous units the Seisian rests on the peneplained. Surface of the crystalline massif, in one of the exposures it overlies the Permian conglomerate of the Verrucano type. Seisian deposits begin with conglomerates or conglomeratic sandstones. Pebbles of siliceous, volcanic and milk-quartz rocks are exotic in character. They are overlain by arkose- and quartzitic sandstones displaying cross stratification, ripple marks and flutes. In the Upper Seisian there is a predominance of silt-clay deposits interbedded by quartz sandstones, in the uppermost part by yellow dolomites. The occurrence is noted of plant remains and of slime-eaters. Illite is here the chief component of clay rocks. An anaIysis of the directional structures shows that the clastic material had been transported from the north southward. The petrographic composition suggests that the material had been brought from massifs built of crystalline, metamorphic and volcanic rocks which make up the Pra-Carpathian massif now completely covered by the Carpathian Flysch. The sedimentary structures and the character of the sediment, fairly uniform over large areas of the Central Carpathians, indicate that the sedimentation of the Lower Werfenian deposits took place in a water basin, most likely in a shallow-sea environment.