New data on heavy minerals from the Upper Cretaceous-Paleogene flysch of the Beskid Śląski Mts. (Polish Carpathians)

Abstract

The types, abundance and origin of non-opaque heavy minerals from 17 samples of sandstones and granule conglomerates of the Godula Beds, Upper Istebna Sandstone, Ciężkowice and Cergowa Sandstone (Upper Cretaceous-Paleogene) of the Beskid OElšski Mts. are described in this study. The descriptions are based on standard optical petrographic investigations and on scanning electron microscope (including electron microprobe) analysis. Garnet, rutile, zircon and tourmaline are the most common types of heavy minerals. Monazite and apatite occur subordinately, whereas epidote and spinel are sporadic. The heavy minerals from the Middle and Upper Godula Beds and the Upper Istebna Sandstone indicate original derivation mainly from metamorphic rocks of granulite and partly eclogite facies. Metasediments were significant constituents, with subordinate granitoids and hornfelses. Granitoids and corresponding pegmatites and aplites, as well as metapelites and metapsammites, appear to be the primary crystalline parent rocks of the Lower Godula Beds and the Ciężkowice Sandstone. Garnet-mica schists with subordinate granitoids and their pegmatites are interpreted as the main crystalline parent rocks of the Cergowa Sandstone. Sporadic chromian spinels and chromian pyrope indicate derivation from mafic and ultramafic rocks. Co-occurrence of rounded and fresh unabraded grains (sometimes euhedral) suggests a mixed provenance for the clastic material, both from crystalline and older sedimentary rocks.