期刊名称：Annales Universitatis Mariae Curie-Skodowska. Sectio B, Geographia, Geologia, Mineralogia et Petrographia
印刷版ISSN：0137-2025
出版年度：2002
卷号：LVII
出版社：Maria Curie-Sklodowska University, Lublin
摘要：The study deals with the Gorajec basin, which belongs to the Por drainage basin - part of the Wieprz drainage basin in the Roztocze. In physiographic terms, the Gorajec basin is situated on the borderline between the Gorajskie Roztocze and the Tomaszowskie Roztocze. It is asymmetric in relation to the meridional valley of the Gorajec. Almost 69% of its area falls within the Gorajskie Roztocze. The basin displays a relatively high relief index - 0.01.
In geological terms, the basin is situated on the Radom-Kraśnik Elevation, transverse to the trend of the Mesozoic Urzędów-Narol Syncline. The northern part of the basin is built of opokas and marly opokas, whereas the southern part - of Lower Maestrichtian gaizes. In the southern part of the basin, Cretaceous rocks are covered by an eroded succession of Miocene sands and Badenian limy-quartzic sandstones. As for Quaternary deposits, loesses and loess-like deposits prevail in the northern part of the basin, while, in the southern part, deluvial and eolian sands are most widely represented.
The valley of the Gorajec formed in a tectonic fault trough is the most easily readable element of relief in the basin. The development of the present valley parallels the proglacial stream valley of the Gorajec whose genesis is linked up with the formation of the Roztocze in the late Sarmatian. The marginal stream valley of the Gorajec was repeatedly used by rivers dewatering the Roztocze in the Pliocene and the Quatenary. The variable intensity of tectonic activity led to considerable changes in the orography of the area.
The dependence of the river system on the magnitude of vertical uplift is fairly well illustrated by the coefficients of drainage basin shape Re and of mountain-front sinuosity S (following Bull, McFadden 1977). These methods were earlier used in the study of mountain areas, as well as of other parts of the Roztocze. The values of coefficient Re indicate a relatively high recent tectonic mobility of the main valley of the Gorajec and the valleys of the Smoryń and the Czarny Stok in the middle part of the Gorajec basin, as well as the Komodzianka and the Chłopków valleys in its northern part. These are the areas following the Gorajec fault trough or faults which trend NW-SE and SW-NE. Areas between Gorajec and Kotówki in the eastern side of the basin and between Trzęsiny and Żelebsko in the western side have been found to be relatively inactive. The remaining area is characterised by relatively low tectonic activity.
The coefficient of mountain-front sinuosity S indicates a distinct recent activity of the Pulczynów-Żelebsko and Ruś-Lipowiec faults and illustrates the intense uplift of the southern part of the Gorajec drainage basin.
Findings of geological and geomorphological surveys and morphometric analyses justify the division of the Gorajec basin into two essential parts: the northern and the southern one. The borderline is formed by relief elements of the Pulczynów-Ruś-Lipowiec morphological line, which follow the trend of border faults separating the Roztocze from the Carpathian Foredeep. Both the northern and the southern parts consist of smaller morphostructural units - microblocks. The Gilów and Komodzianka microblocks in the northern part of the Gorajec basin, and the Pulczynów, Czarny Stok and Lipowiec microblocks in the southern part, are tectonically most mobile.
The dynamics of recent tectonic activity is particularly well readable in the southern part of the drainage basin and appears to parallel the trend of faults in the Mesokenozoic succession of rocks.
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