CRYSTALLOCHEMICAL RECORD OF THE ORIGIN OF SMECTITE MINERALS IN MARLS OF THE FLYSCH CARPATHIANS (EXAMPLES FROM THE SUB-SILESIAN UNIT)

摘要

Marls are fairly common and important but till now only occasionally iiwestigated components of the Carpathian flysch. Though their presence in various profiles of the Flysch Carpathians is the basis for their lithostratigraphic subdivision and some marls represent individual members or formations, the reasons of their appearing among sandstones and shales hare been often not convincingly explained. Four facies varieties of the Upper Cretaceous marls of the Sub-Silesian Unit were selected for these studies. They are variegated Węglówka marls, widespread in the eastern part; of the study area; grey Frydek marls, occurring in the western part; and locally appearing creamy Jasienica marls and white Żegocina marls. The dominant clay mineral in these rocks is smectite. The author attempted to recognize genetic information recorded in crystallochemical properties of this mineral and to relate it to the conditions of smectite origin and to the influence of later environmental factors.