Pstre łupki z Miłkowej i budowa geologiczna obszaru otaczającego

Abstract

VARIEGATED SHALES FROM MIŁKOWA AND GEOLOGY OF THE ADJACENT AREAThe area under discussion constitutes the southern part of the Silesian unit (Middle Carpathians). Here, the following members were distinguished: Jankowa anticline, Bobowa syncline, and Rożnów anticline. In this latter numerous exotics occur at the bottom of the uppermost Ciężkowice strata. There are represented here microcline-biotite granites; microcline, dimica and biotite gneisses; augen-gneisses; sacchrites; sericite and biotite phyllites; quartz and feldspar veins as well as grey marbles, titanium amphibolites; and granodiorite porphyries. Almost all of them are characteristic of catablastic structures. The sedimentary rocks are represented by light-brown limestones with flints, containing numerous sponge spicules, echinoid spines, and few Calpionellae resembling Tintinopsella carpathica. Moreover, here occur white reef, oolitic and Nerinea limestones, too. The limestones are Upper Jurassic. Fairly often also bryozoan and lithotamnian limestones appear, as well as limestones and sandstones containing Nummulites and Discocyclinae are present.Amidst the Krosno beds, north of the Jankowa fold, there occurs, wedged in from above, a small complex of variegated shales. Microfaunistic examinations disclosed that there occurs probably a full profile from the Senonian up to the higher part of the Eocene. It results of the stratigraphic and tectonic considerations that these shales, most probably represent the Silesian series in an almost exclusively argillaceous fades, which might have been formed at the periphery of an arenaceous fades. This suggests that the Upper Cretaceous and the Eocene of the Silesian series passed southwards, similarly as in the north, into an argillaceous facies. It is also possible that more to the south, a transition into a marly facies, existed there. This is proved by the fact that in the Krosno beds, the material of which was in this area transported from southwest, there sometimes occur rather numerous Globotruncana and, sporadically, test fragments of Inoceramian.