Commune: Łącko (pow. nowosądecki, woj. małopolskie)
Framework element or context represented:
Stratigraphy of the Magura unit.
Primary geological/geomorphological interest:
Stratotype of the Zarzecze Formation – flysch of the Outern Carpathians, Magura Unit, Krynica subunit.
Comparative assessment justification:
The type sequence of the Zarzecze Fm detaily examined and interpreted, well exposed (renewed by water erosion). Reference profile of the Zarzecze Fm are situated in Życzanów 20 km far from the Zarzecze site.
Protection status and accessibility:
Proposed for protection, well accessible, illustrative and useful for education.
Character of site: Natural outcrop.
Area: 0.5 ha
Altitude: 355-370 m a.s.l.
Lithology: sandstones, shales, silstones, claystones
Discipline: Palaeobiology, Palaeoenvironment, Stratigraphy of Phanerozoic
Process Age: *all periods
Bedrock Age: Paleogene, *all periods
Description of primary interest:
The sequence of flysch rocks is exposed in steep slope of Dunajec river valley just above the water table. The outcrop is about 350 m long and up to 10 m high. The rocks are inclined to the southwest (SSW - 55º). In the eastern part of the site, at the distance long 30-40 m, grey, thick-bedded, coarse grained and even conglomeratic sandstones of the Życzanów Member of the Szczawnica Formation are exposed. They form outcrops, even some small crags on the river bank. The rocks of the Zarzecze Formation stratigraphically overlying the Życzanów Member occur in the central and western part of the site, but lower section of the sequence (in the central part of the site) is poorly exposed (just on the water level). Western part of the site represents high, bare rock wall, slowly but constantly undercut by river. It is formed of greenish-grey, thin-bedded sandstones interbedded with marly shales (siltstones). The sandstone/shale rate is 55:45. On the sandstone bedding planes mechanical hieroglyphs as well as biogenic trace fossils are observed. These rocks represent distal turbidite sediments of outer submarine fan at the bottom of the Magura basin – geosynclinal basin situated in the northern peripheral part of the Neotethys ocean. In the Magura Unit (basin) four subunits are distinguished. Zarzecze Fm belongs to sequence of Krynica subunit. In neighbouring Bystrica subunit facial equivalents of it are Beloweža Fm and Żeleźnikowa Fm.
Literature:
ALEXANDROWICZ Z. (ed.), MARGIELEWSKI W., URBAN J., GONERA M. 1996–Geoconservation of the Beskid Sądecki Mountains and the Sącz basin, Polish Carpathians (English sum.). Studia Naturae 42, 148 pp. ALEXANDROWICZ Z., POPRAWA D., RĄCZKOWSKI W. 1999–Stratotypes and other important geosites of the Polish Carpathians. Pol. Geol. Inst., Spec. Papers, 2: 33-46. BIRKENMAJER K., OSZCZYPKO N. 1989–Cretaceous and Paleogene lithostratigraphic units of the Magura Nappe, Krynica subunit, Carpathians. Ann. Pol. Soc. Geolog. 59: 145-181. GOLONKA J., OSZCZYPKO N., ŚLĄCZKA A. 2000–Late Carboniferous-Neogene geodynamic evolution and paleogeography of the circum – Carpathian region and adjacent areas. Ann. Soc. Geol. Pol 70, 2: 107-136. OSZCZYPKO N. 1985–Stop 69: Zarzecze. In: Birkenmajer K. ed., Main geotraverse of the Polish Carpathians, Guide to excursion 2, Carpatho-Balkan Geol. Assoc. XIII Congr., Geol. Inst., Warsaw: 179-180. OSZCZYPKO N. 1986–Wycieczka B.18. Zarzecze (Polish only). In: Birkenmajer K. ed., Przewodnik 57 Zjazdu Pol. Tow. Geol., Inst. Geolog., Kraków: 130-131. OSZCZYPKO N. 1992–The Late Cretaceous through Paleogene evolution of Magura. Geol. Carpathica 43, 6: 333-338. OSZCZYPKO N., DUDZIAK J., MALATA E. 1990–Stratigraphy of the Cretaceous through Paleogene deposits of the Magura nappe in the Beskid Sądecki range, Polish Outer Carpathians. Studia Geol. Pol. 97: 109-181. UCHMAN A. 1991–Trace fossils from stress environments in the Cretaceous-Paleogene flysch of the southern part of the Magura nappe, Polish Outer Carpathians. Ann. Soc. Geol. Pol., 61: 61-75.