PODGRODZIE NAD WISŁOKĄ (PODGRODZIE ON THE WISŁOKA RIVER)



Commune: Pilzno (pow. dębicki, woj. podkarpackie)

Framework element or context represented:
Quaternary biostratigraphy.

Primary geological/geomorphological interest:
Holocene succession of sediments, plant and mollusc assemblages.

Comparative assessment justification:
Complete sequence of deposits indicating climatic and environmental changes of the Carpathian Foredeep during the Early and Middle Holocene. Similar profils are near Dębica.

Protection status and accessibility:
Projected documentary site of inanimate nature.

Character of site: Natural outcrop.

Area: 0.3 ha

Altitude:

Lithology: gravels, sands, clays, silts, clays, peats

Discipline: Palaeobiology, Stratigraphy of Quaternary

Process Age: Holocene, *all periods

Bedrock Age: Holocene, Pleistocene, *all periods




Description of primary interest:
The locality is situated on the right bank of the Wisłoka River in Carpathian Foredeep. The profile of terrace sediments is composed of sands and gravels overlaying by silts, clays and peat intercalated by sands. The age of this sequence was determinate using radiocarbon method 33-7 ka BP. The evolution of the environment was recontracted on a base of detail palynological and malacological analysis supplemented by lithological studies. The complex of deposits begins with colluvia developed as clays and sandy clays with angular debris and flow structures. They are covered with fluviatile sands and gravels passing upward by sands deposited at the flood plain. In the second stage the small oxbow lake was formed. It was gradually overgrowed by plants, filled by sediments and finally transformed into peatbog. Palynological diagram demonstrate the succession of plant communities following the changes of the climate and evolution of environment. The succession of molluscan assemblages characterizes the transformation of oxbow in particular phases.

Literature:

ALEXANDROWICZ S.W. 1980-Early-Holocene molluscs in Podgrodzie in Wisłoka valley (English sum.). Rocz. Pol. Tow. Geol. 50 (3-4): 391-408.     DANEK M. 2002-Profils of quaternary terrace sediments of the Wisłoka River valley near Dębica (English sum.). Chrońmy Przyr. Ojcz. 58, 5: 44-56.     MAMAKOWA K., STARKEL L. 1977-Stratigraphy of Late Glacial and Early Holocene aluvia at Podgrodzie on the Wisłoka-River (SE Poland). Stud. Geomorph. Carp.-Balc. 11: 101-110.     NIEDZIAŁKOWSKA E., SKUBISZ A., STARKEL L. 1977-The Lithology of Late Glacial and Holocene aluvia at Podgrodzie on the Wisłoka-River. Stud. Geomorph. Carp.-Balc. 11: 89-100.