- Tytuł:
-
Cechy sedymentologiczne i wiek osadów równiny zalewowej Słupi
Sedimentological features and age of the deposits in the flood plain if the Slupia river - Autorzy:
- Florek, W.
- Powiązania:
- https://bibliotekanauki.pl/articles/2085660.pdf
- Data publikacji:
- 1988
- Wydawca:
- Uniwersytet Warszawski. Wydział Geografii i Studiów Regionalnych
- Tematy:
-
rzeka Slupia
rownina zalewowa
cechy sedymentologiczne
osady
cechy morfologiczne
budowa geologiczna - Opis:
- The investigations carried out by the author up to the present place the age of the Słupia river flood plain in the sub-Atlantic period - 1850±110 B.P. Gd.-864. The deposits forming the flood plain reach ca 4 m of thickness and they are underlain by older deposits including grey boulder clay defined as older clay from the last glaciation (the Vistulian). The differences in the lithological development of deposits in the river-bed and beyond it in both investigated points, result both from natural causes (accumulating effect of the „Bydlino threshold” in reference to the investigation point in Słupsk) and from anthropogenic factors (accumulating effect of damming-up devices in Słupsk and the draining effect of subterranean erosion below the Krzynia dam - in reference to the investigation point at Dębnica Kaszubska). The quartz grain rounding of the deposits is poor both in the flood plain and on the terrace lying above it. They contain large quantities of α-type grains and a very small amount of γ-type grains which makes the deposits resemble morainic and even waste deposits. The features of the quartz grain surface evaluated under the scanning microscope and the binocular have confirmed the conclusion of the low degree of fluvial grain abrasion. A striking fact is the large number of corrosive pits due to the effect of a strongly chemically active environment. It is possible that it was a pelagic environment (Eems sea). Similar marks of the survival of features of another environment have been observed on the grain surface of some heavy minerals the composition of which has also confirmed the low degree of fluvial abrasion of the deposits. The composition of heavy mineral is the proof of an increased inflow of morainic and fluvioglacial material coming from the denudation and erosion of post-glacial deposits. It may be connected not only with the commonly observed Holocene tendency of low-land rivers to cut into the ground, but also with increased denudation of the drainage area due to intensified settlement in the river valley and on its slopes. All the investigations have shown the low degree of fluvialisation of the deposits. Preciser technics (in the analysis of the surface of quartz grains and of some heavy minerals) have revealed some features of deposits connected with the environments in which the deposits were accumulated, then incorporated into the mass of the Vistulian ice-sheet and carried by it into the area of Pomerania. The action of the Vistulian glacial environment, towards its close, and of the late glacial and Holocene fluvial environment has not been able to efface those features.
- Źródło:
-
Prace i Studia Geograficzne; 1988, 09; 75-103
0208-4589 - Pojawia się w:
- Prace i Studia Geograficzne
- Dostawca treści:
- Biblioteka Nauki
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