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The Pieniny Klippen Belt is in geology a tectonically and orographically remarkable zone in the Western Carpathians, with a very complex geological structure.〔Mišík, M., 1998: ''Slovakia.'' in Moores, E.M., Fairbridge, R.W. (Editors), 1998: ''Encyclopedia of European and Asian Regional Geology.'' Encyclopedia of Earth Sciences Series, Springer, London, p. 656-664〕 It is a narrow (only 0.4 to 19 km) and extremely long (about 600 km) north banded zone of extreme shortening and sub-vertical strike-slip fault zone, resulting from subduction of the Piemont-Liguria Ocean (which is called the Vahic or Pieninic ocean in the Western Carpathians), where only fragments of individual strata and facies are preserved. The Pieniny Klippen Belt is considered one of the main tectonic sutures of the Carpathians and forms the boundary between the Outer (externides a thin-skin thrustbelt) and Central Western Carpathians (internal thick-skin thrustbelt). The Pieniny Klippen Belt emerges from beneath the Neogene sediments of the Vienna basin near Podbranč in western Slovakia and continues eastward to Poland, where it bends and returns to Slovakia in the area of Pieniny. The klippen belt then continues to Ukraine and ends in Romania. In some places it is covered with younger deposits, for example in the Podhale basin in Poland, or in the Vihorlat Mountains in Slovakia. Klippes, which are the most characteristic features of the belt, are Jurassic to lower Cretaceous lenses - rigid blocks of limestone, tectonically separated from their unknown substratum. These blocks are also cropping out in tectonic windows in the overlying middle Cretaceous to Paleogene sediments. Strong tectonic deformation is a result of two main phases during the Alpine orogeny. The oldest phase is called the Laramide phase or Jarmuta phase and occurred in the Cretaceous and Paleogene periods. It caused thrusting of the nappes. The second phase is called the Savian or Helvetian phase. It was induced by subduction of the Northern Penninic ocean and caused the formation of the Carpathian Flysch Belt. == Geological structure == The Pieniny Klippen Belt is divided into numerous tectonic units, but only few of them occur throughout the entire belt. The oldest rocks of the Klippen belt are Middle Jurassic to upper Cretaceous. They are in normal stratigraphical positions, with only minor hiatus. Large scale crustal shortening caused rocks of different tectonic units and origin to be thrusted over each other and now lying juxtaposed. These tectonic units are: #The Czorsztyn unit, named after Czorsztyn in Poland, is found in the most northern part of the Klippen Belt. It consists of shallow marine sediments, usually Jurassic nodular limestones and Cretaceous so called ''couches rouges'' marlstones.〔·Biely, A. (Editor), Bezák, V., Elečko, M., Gross, P., Kaličiak, M., Konečný, V., Lexa, J., Mello, J., Nemčok, 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.〕 #The Kysuca unit (also known as Kysuca-Pieniny unit). The Jurassic sediments of this unit are mostly deep marine in origin (typical radiolarites). Most of the other tectonic units were deposited between the shallow Czorsztyn and deep marine Kysuca unit. #the Pruske unit (also known as the Niedzica or Czertezik unit) has a transitional facies between shallow and deep marine environments.〔Mišík, M., 1997: ''The Slovak Part of the Pieniny Klippen Belt After the Pioneering Works of D. Andrusov.'' Geologica Carpathica, 48, 4, p. 209-220〕 #The Klape unit composed of cretaceous turbiditic sediments containing exotic conglomerates with pebbles from an unknown source area. It is probably an acretionary wedge or some unknown terrane carried by the Fatric, but its origin is still a subject of discussion. # Orava unit with typical limestones with unique ammonite fauna, typical klippes occur only in Orava region.〔 #The Manín unit contains typical Urgonian limestone. It has only partially a tectonic style of klippes,〔Mišík, M., Chlupáč, I., Cicha, I., 1984: ''Historická a stratigrafická geológia.'' SPN, Bratislava, 541 pp. 〕 It is usually assigned to the Fatricum as well as the Drietoma and Haligovce units. Its origin is still disputed, because some geologists consider it a proximal part of the Tatric sedimentary cover.〔Andrusov, D., 1968: ''Grundriss der Tektonik der Nördlichen Karpaten.'' Verlag der Slowakishen akademie der Wissensshaften, Bratislava, 188 p.〕 The Czorsztyn unit has the shallowest marine facies. Together with smaller continental slope units and the deep marine Kysuca unit it forms a continental domain called the Oravicum,〔Maheľ, M., 1986: ''Geologická stavba československých Karpát / Paleoalpínske jednotky 1.'' Veda, Bratislava, 503 pp. 〕 which is geometrically equivalent to the Briançonnais microcontinent in the Western and Central Alps.〔Tomek, Č., 1993: ''Deep crustal structure beneath the central and inner West Carpathians.'' Tectonophysics, 226, p. 417-431〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pieniny Klippen Belt」の詳細全文を読む スポンサード リンク
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