Porównanie zespołów minerałów ciężkich fliszu podhalańskiego, aalenu fliszowego w pasie skałkowym i egzotyków jurajskich z Bachowie

Jan Łoziński


The comparison of the assemblage of heavy minerals of the Podhale Flysch, Flysch Aalenian ijn the Klipen Belt with the Jurassic exotics from Bachowice

Continuing the studies of heavy minerals of the sediments of the Inner Carpathians the investigations concerning the Podhale Flysch and the Aalenian Flysch of the Pieniny have been concluded. The results of the studies, presented in Plate I (Polish text), where also the heavy minerals separated from the exotic Bajocian sandstones of Bachowice have been put under consideration, show that the heavy concentrates consist of the most stable minerals only, such as zircone, rutile, tourmaline, garnet, staurolite. The Podhale Flysch and the Aalenian Flysch are characterized by the excess of garnet over the remaining heavy minerals. These assemblages differ only in the contents of trace minerals. In the Aalenian Flysch there are present chlorite, biotite, anatase, barite and traces of disthene while the Podhale Flysch shows the presence of chloritoid, apatite and traces of epidote. It is interesting that staurolithe present in the Aalenian appears only in the Ostrysz beds which are the youngest section of the Podhale Flysch. The assemblage of heavy minerals of the exotic sandstones of Bachowice, although qualitatively similar to those mentioned above, differs from them by the excess of zircone over the remaining minerals. The determination of the ratio of the euhedral and anhedral rounded zircone grains has made possible to distinguish some strata in which the appearance of great quantites of the euhedral zircone grains and the zoisite and biotite minerals points out to the supply of fresh material during the sedimentation of the discussed sandstones. The presence of assemblages consisting mainly of strongly resistant minerals allows to assume that the clastic material might derive in major partie directly from the erosion of some sedimantary rocks. This erosion might in places reach the crystalline rocks. The sandstone of Bachowice especially represent a material which apparently underwent many sedimentary cycles for which speaks the dominant role in the concentrates of zircone and especially of rounded zircone. The assemblage of following minerals: zircone, rutile, tourmaline, garnet and staurolite points out th at the initial clastic material originates from the erosion of rooks comprising the granite intrusions in crystalline schists, what concerns the Aalenian Flysch and the Jurassic exotics of Bachowice. So far as the Podhale Flysch is concerned, where th e set consists of zircone, rutile, tourmaline, garnet, apatite and traces of chloritoid, the initial clastic material might have come from the area of injection gneisses and aplitic granites in which the intercalations of chloritoid shales might have been present.

Full Text: