Interglacjał wielki i osady starszych zlodowaceń•w Uciechowie na Dolnym Śląsku

Abstract

W artykule scharakteryzowano osady mułkowe występujące między poziomami glin zwałowych w otworach wiertniczych koło Uciechowa (środkowa część Kotliny Dzierżoniowskiej). Stratygraficznie osady te zaliczono do interglacjału wielkiego. Przynależność tę potwierdziły badania palinologiczne, wykonane przez P. Szczypka.GREAT INT·ERGLACIAL AND OLDER GLACIATION DEPOSITS FROM UCIECHÓW IN LOWER SILESIAThe analysis of borehole columns and geological cross-sections has shown that the river erosion from the end of the Pliocene cut Tertiary sedimentary cover down to the bedrock in the Uciechów area. The oldest till of that region, about 30 m in thickness, was deposited on the sockle of Sowie Góry gneisses at the bottom of the valley. In the cataglacial phase of that Glaciation the till cover was incised and the valley infilled with fluvial gravels 20 m thick. The gravels are sometimes covered with a 5-meter layer of silts presumably related to the older Interglacial.Two subsequent till horizons, 20 m and 5 m in thickness, originated during the South-Polish Glaciation. During the Great Interglacial the valley was cut down to 40 m depth, older loamy gravel deposits removed and a new, 35-meter series of fluvial gravels deposited. The gravels are covered with 25-meter series of Great Interglacial lacustrinal silts in valley depressions. The Interglacial deposits are covered by a series of bottom-moraine and fluvioglacial deposits related to deglaciation of the Mid-Polish icesheet. The deglaciation was primarily areal in nature in the forefield of the Central Sudety Mts. Sandy gravel hummocks from the Uciechów area represent kames. The glacitectonic deformations displayed by them evidence oscillations of retreating icesheet. Erosional incision of river valleys and denudation of till covers on highlands took place during the Eemian Interglacial and deposition of 5-meter series of sandy-silty muds - during the Holocene.