Rozwój strefy glacimarginalnej na przedpolu Beskidu Śląskiego (dział bielski Pogórza Śląskiego)
Abstract
Evolution of the glaciomarginal zone in the Silesian Beskid foothill (Bielsko division of the Silesian Foothills).
A b s t r a c t. The paper presents the succession of Sanian Glaciation sediments recognized in the Świętoszówka site, southern part of the Silesian Foothills (Bielsko division). The following deposits were found: a unit of gravels deposited in a system of foremountain alluvial fans, a unit of silts deposited in a glaciomarginal dammed lake, and a glacial till. Glaciogenic deposits are covered with loess-like deposits. The development of the glaciomarginal zone was influenced mainly by the pattern of basement relief. In the northern part of the foothill, in the northward-oriented valleys, glacially dammed lakes weremainly formed. During transgression, water from these reservoirs was pushed in front of the ice-sheet margin towards the southern part of the low-relief foothill. The individual lakes probably merged there into one larger glaciomarginal lake. It was characterized by low-energy conditions and deposition mainly from suspension. Sedimentation style in the lake changed over time and was dependent on the size and shape of the lake and its position in relation to the ice-sheet margin, which determined the width and distribution of zones of sediment supply and the dynamics of depositional processes in the lake.
A b s t r a c t. The paper presents the succession of Sanian Glaciation sediments recognized in the Świętoszówka site, southern part of the Silesian Foothills (Bielsko division). The following deposits were found: a unit of gravels deposited in a system of foremountain alluvial fans, a unit of silts deposited in a glaciomarginal dammed lake, and a glacial till. Glaciogenic deposits are covered with loess-like deposits. The development of the glaciomarginal zone was influenced mainly by the pattern of basement relief. In the northern part of the foothill, in the northward-oriented valleys, glacially dammed lakes weremainly formed. During transgression, water from these reservoirs was pushed in front of the ice-sheet margin towards the southern part of the low-relief foothill. The individual lakes probably merged there into one larger glaciomarginal lake. It was characterized by low-energy conditions and deposition mainly from suspension. Sedimentation style in the lake changed over time and was dependent on the size and shape of the lake and its position in relation to the ice-sheet margin, which determined the width and distribution of zones of sediment supply and the dynamics of depositional processes in the lake.