Petrographic variability of Carpathian sandstones and the problem of sandstone classification

Abstract

Zmienność petrograficzna piaskowców kambryjskich i zagadnienia ich klasyfikacji In the present study, the variability in mineral composition of some sandstones from the Polish Flysch Carpathians is discussed, together with the problem of their classification. This variability is sometimes very marked, becoming conspicuous in particular stratigraphic and facies horizons and even within single beds. Although such variability calls for the application of a relatively simple petrographic classification, sandstones from the same stratigraphic and facies horizon usually occur in several fields, representing different petrographies. Furthermore, samples from one and the same bed may represent different 'types of sandstone. This arises from changes in grain-size, caused by the existence of graded bedding. In the Polish Flysch Carpathians, greywaeke — sandstones predominate, and to a lesser extent, oligomictic and arkosic sandstones occur. Greywackes and quartz sandstones are found more rarely, and arkoses seldom occur.