Uwagi o pozycji stratygraficznej żwirów w liasie świętokrzyskim
Abstract
REMARKS ON THE STRATIGRAPHICAL POSITION OF GRAVELS IN LIAS OF THE ŚWIĘTY KRZYŻ MTS
Summary
Within the Liassic deposits of the Święty Krzyż Mts region there is known the occurrence of a thick gravel complex. This complex consists of alternating banks of quartzo-quartzitic gravels and various grained sandstones with clay interbeddings and clay balls. In several outcroppings occurring in the north-western portion of margin of the Święty Krzyż Mts, the thickness of the complex said amounts about 20 m and more. Stratigraphical position of gravel complex, because of complicated conditions of its occurrence, was not hitherto exactly established. This complex has been referred by individual authors to the Keuper, Rhaetic and Lower or even Middle Lias.
The present paper deals with some premises based on the results of bore-holes recently carried out, showing at the occurrence of two separate gravel complexes within the area discussed, viz.: the older and younger ones.
The older gravel complex of considerably lesser thickness (to about few meters) occurring only in the north-eastern margin of the Święty Krzyż Mts should be referred to the bottom part of the Lias α1. The younger one, investigated in the northwestern and northern margin of the Święty Krzyż Mts is thought to be correlated with the lower part of the Lias α2.
Summary
Within the Liassic deposits of the Święty Krzyż Mts region there is known the occurrence of a thick gravel complex. This complex consists of alternating banks of quartzo-quartzitic gravels and various grained sandstones with clay interbeddings and clay balls. In several outcroppings occurring in the north-western portion of margin of the Święty Krzyż Mts, the thickness of the complex said amounts about 20 m and more. Stratigraphical position of gravel complex, because of complicated conditions of its occurrence, was not hitherto exactly established. This complex has been referred by individual authors to the Keuper, Rhaetic and Lower or even Middle Lias.
The present paper deals with some premises based on the results of bore-holes recently carried out, showing at the occurrence of two separate gravel complexes within the area discussed, viz.: the older and younger ones.
The older gravel complex of considerably lesser thickness (to about few meters) occurring only in the north-eastern margin of the Święty Krzyż Mts should be referred to the bottom part of the Lias α1. The younger one, investigated in the northwestern and northern margin of the Święty Krzyż Mts is thought to be correlated with the lower part of the Lias α2.