Pieniny Klippen Belt

From Wikipedia, the free encyclopedia

Pieniny Klippen Belt is tectonically, orographically significant zone of Western Carpathians, with very complicated geological structure. It is a narrow (only 0.4 to 19 km) and extremely long (about 600 km) north banded zone of extreme shortening, after subduction of southern part of Piemont-Liguria Ocean, where only a fragments of strata and facies are preserved. Pieniny Klippen Belt is considered as one of the main tectonic suture of Carpathians and boundary between Outer (Externides) and Central Western Carpathians (Internides).

Pieniny Klippen Belt emerges from beneath the neogene sediments of Vienna basin near Podbranč in Western Slovakia and continues eastward to Poland, where it bends and returns to Slovakia in area of Pieniny. Klippen belt then continues to Ukraine and ends in Romania. On some places it is covered with younger formations, for example in Podhale basin in Poland, or in Vihorlat Mountains in Slovakia.

Klippes or cliffs, which are the most characteristic features of belt, are Jurassic to lower Cretaceous lenses - rigid blocks of limestone, tectonicaly separated from their unknown substratum. These blocks are also penetrating throught the overlying middle Cretaceous to Paleogene sediments. Strong tectonic deformation is a result of two phases of Alpine orogeny. First of them, the Laramide phase (or jarmuta phase), occurred within Cretaceous and Paleogene and caused thrusting of nappes. Next Savian or Helvetian phase, which was induced by subduction of Norhern Penninic ocean, caused formation of Carpathian Flysch Belt.

[edit] Geological structure

Pieniny Klippen Belt is devided into numerous tectonic units, but only few of them occur in entire belt. The oldest rocks of klippen belt are known only since Middle Jurassic to upper Cretaceous, which are in normal stratigraphical position only with minor hiatus. Enormous shortening caused, that rocks of different tectonic units and origin occure close to each other, or are pushed up and over another. At present these tectonic units are known:

1. Czorsztyn unit, named after locality Czorstyn in Poland, is the most Northern, consists of shallow watter sediments, usually Jurassic nodular limestones and Cretaceous so called couches rouges marlstones^[1].
2. Kysuca unit (also known as Kysuca-Pieniny unit), it's Jurassic sediments are mostly deep water origin (typical radiolarites)
3. Pruske unit (also known as Niedzice unit or Czertezice unit) is transitional unit between shallow and deep water environment^[2].
4. Klape unit consists of exotic conglomerate pebbles of unknown origin, it is probably an acretionary wedge or some unknown Terrane carried by Fatric, but it's interpretation is still a subject of discussion
5. Orava unit with typical limestones with unique ammonite fauna, typical klippes occur only in Orava region^[2].
6. Manín unit consists of typical ugronian limestone, only with partly klippen tectonic style,^[3] it's usually assigned to Fatricum as well as Drietoma and Haligovce unit.

Czorsztyn and Kysuca unit together form an continental domain called Oravicum.^[4]

[edit] References

1. ^ ·Biely, A. (Editor), Bezák, V., Elečko, M., Gross, P., Kaličiak, M., Konečný, V., Lexa, J., Mello, J., Němčok, J., Potfaj, M., Rakús, M., Vass, D., Vozár, J., Vozárová, A., 1996; Explanation to geological map of Slovakia 1:500 000. Dionýz Štúr Publishers, Bratislava, 76 pp.
2. ^ ^{a b} Mišík, M., 1997 The The Slovak Part of the Pieniny Klippen Belt After the Pioneering Works of D. Andrusov. Geologica Carpathica, Volume 48, number 4/1997, 209-220 pp.
3. ^ Mišík, M., Chlupáč, I., Cicha, I., 1984. Historická a stratigrafická geológia. SPN, Bratislava, 541 pp. (Slovak)
4. ^ Maheľ, M., 1986. Geologická stavba československých Karpát / Paleoalpínske jednotky 1. Veda, Bratislava, 503 pp. (Slovak)