The mineral composition of the Pannonian s.l. Formations in the Hungarian Plain (I). The characteristics and origins of the Pannonian s.l. sands and sandstones

Abstract

; The composition and origin of sediments transported from different directions into Lake Pannon -
which was on the area of the Hungarian Plain during the Late Miocene - Pliocene (Pannonian s. 1.) -
were studied on the basis of the available heavy mineral data of 868 sand and sandstone samples from
53 boreholes. Statistical methods were also used arid the depositional facies were taken into account.
Based on the results of cluster and discriminant analyses, characterize the mineral composition of
sediments which came from different directions could be characterised, the-transport directions based on
seismic interpretations could be corrected, and transport directions far from the source areas could be
deduced (e.g. sands coming from NW reached the middle and southern parts of the Hungarian Plain). The
results of correlation analysis indicate the origin of some minerals and also point towards selective sorting.
The occurrence of heavy minerals shows that the detritus of the low grade metamorphic rocks of the
Carpathians; and recycling of older sedimentary rocks (primarily flysch sediments of the surrounding
areas) spread almost over the whole area that was studied. Minerals that originated from medium- and
high-grade metamorphic rocks are most abundant in the NW, in the fluvial sands of the Jászság Basin
and the Danuhe-Tisza Interfluve. These minerals originated in the Western Carpathians, the Alps and
the Bohemian Massif. In the sands that came from the NE, minerals from the Inner Carpathian volcanites
are characteristic!; they are most frequent in the North part of the Transtisza region, but also occur in its
southern part, an d in'Other areas, too. The-sediments which came from the SE and Е into the Hungarian
Plain are subordinate in quantity and have a varying composition. They originated from the Apuseni
Mountains.