Commune: Krasiczyn (pow. przemyski, woj. podkarpackie)
Framework element or context represented:
Biostratigraphy and palaeoenvironment of Pleistocene.
Primary geological/geomorphological interest:
Profile of the younger Pleistocene terrace evidenced by molluscs, TL dating and pollen analysis.
Comparative assessment justification:
Unique locality of well docunetated Early – Late Vistulian mollusc-bearing deposits in the Polish Carpathians.
Protection status and accessibility:
Proposed to protection as documentary site.
Character of site: Natural outcrop.
Area: 0.3 ha
Altitude: 235 m a.s.l.
Lithology: gravels, clays, silts, clays, loesses
Discipline: Palaeobiology, Palaeoenvironment, Stratigraphy of Quaternary
Process Age: Pleistocene, *all periods
Bedrock Age: Pleistocene, *all periods
Description of primary interest:
Sediments build a 12 m high terrace of Vistulian age. It is crop out along the left bank of the Krzeczkowski Stream over the distance of about 100m. The sequence comprises from the bottom upward: gravels, sandy muds, loess and solifluction loams. The bedrock is composed of flysch deposits of the marginal Skole Unit. The oldest event registered in profile is connected with accumulation of gravels corresponding with Brǿrub interphase this period is evidenced by a rich and differentiated fauna of molluscs and thermoluminiscence data. The gravels were covered by muds and solifluction sediments. And finally by loesses. A rich and differentiation molluscan assemblages have been found in these sediments. The oldest molluscan community corresponds with a temperate cool and boreal climate and occurrence of coniferous forests. This fauna passing upward into assemblage typical for cold climate and open environments. The youngest elements of this succession are typical for the loess sequences and correspond with cold climate. Holocene terraces of the Krzeczkowa Stream contain a rich molluscan fauna with domination of the forest snails.
Literature:
ALEXANDROWICZ S. W., ŁANCZONT M. 1995–Loesses and alluvia in the Krzeczkowski Stream Valley in Przemyśl environs (SE Poland). Ann. UMCS, sec. B 50: 29-50. ALEXANDROWICZ Z., POPRAWA D., RĄCZKOWSKI W. 1999–Stratotypes and other important geosites of the Polish Carpathians. Pol. Geol. Inst., Spec. Papers, 2: 33-46. ŁANCZONT M. 1993–Accumulation conditions of the Pleistocene loess deposits in the San river valley in Przempt environs (English sum.). Kwartalnik AGH, Geologia 19, 2: 75-108. ŁANCZONT M. 1995–Regional stratigraphy and lithology of the Carpathian loess deposits in Przemyśl environs. Bull. Pol. Acad. Sci. Earth Sci. 43,1: 43-56. MARUSZCZAK H. 1991–Main sections of loesses in Poland (English sum.). Publ. M. Curie - Skłodowska University, pp 200.