Краковско-Ченстоховская Юра - About Jura
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About Jura

The Kraków-Częstochowa Upland (Jura)

The Kraków-Częstochowa Upland (Jura), which is a part of the Silesia-Kraków Upland, comprises of a vast plate of Upper Jurassic limestone rising to an average of 300 m asl in the area of Częstochowa and to 400-500 m asl near Kraków. It is slightly inclined towards the North-East, where it gradually depresses underneath younger Cretaceous formations of which the Przedborska Upland and Nida Basin with its mesoregion Miechów Upland are built. From the North the Jurassic plate is indented by a gorge valley of the river Warta, which marks the border with Wieluńsko-Woźnicka Upland. In the South the Kraków-Częstochowa Upland is devided by the Biała Przemsza-Szreniawa tectonic depression into its mesoregions: Czestochowa Upland and Olkuska Upland, often called the Ojcowski Plateau.
Similiarly, the Kraków-Krzeszowice-Trzebinia tectonic depression (due to its extent deemed a mesoregion) where Krzeszowice Graben separates Olkuska Upland from Teńczyński Ridge, which descends towards the valley of the Vistula in the South, to be exact, towards the tectonic depression of Kraków Gate. It is a macroregion characterized by multiple geomorphological peculiar to other surrounding regions, including horst limestone hills. Hence the Kraków Gate is regarded by some scholars as part of the Kraków-Częstochowa Upland, which is reflected, for example, in the establishment of Jurassic landscape parks on its territory.

From the West Częstochowa Upland falls into the Lowering the Upper Warta (Woźnicko-Wieluńska Upland) in a steep, reaching up to 100m asymmetric ridge, called cuesta. Less significant eastern boundary with the Lelowski Cuesta (Przedborska Upland) runs on the Mstów - Lelów - Pradła – Wolbrom line. Characteristic elements of landscape in Częstochowa Upland include Upper Jurassic limestone monadnocks, reaching several dozen meters and rising above the relatively flat level of its hilltops. They form large groups of rock, hillocks (like Janowski Mountain, the highest elevation of the Jura, of 515.5 m asl) and mountain ranges fragmented by valleys, generally dry, filled with sands, or draining water only periodically. Similarly, the Jura cuesta running irregularly between Olkusz and Trzebinia, lonely monadnocks sticking out on hilltops, with another Jura summit - Skałka 502 (512.8m asl) define Olkuska Upland. However, for the landscape of the southern part of the mesoregion characteristic are the stream valleys. Up to 100m deep, with steep, rocky slopes, they are commonly referred to as valleys of Kraków or the vicinity of Kraków. The most known and valuable is Prądnik Valley, within which Ojcowski National Park has been established. From among other valleys, lets mention only the nature reserves: Bolechowicka, Szklarki, Racławka Eliaszówka or one of the most famous tourist destinations, namely Będkowska Valley, and the longest of them Dłubnia Valley, which separates Olkuska Upland from Miechowska Upland. In western Olkuska Upland the valleys are intersected by older fromations. The Upper Jurassic limestones cut here reveal rocks of the Triassic, Permian (volcanic), Carboniferous and Devonian (Racławka Valley, Czernki, Miękinka and others) periods underneath. Tenczyński Ridge, stretching from Chechło Valley in the West to Kraków, has similar structure and terrain. In the western part there are, for example, Carboniferous formations containing black coal seams (Tenczynek) and hard volcanic rocks, which build hills. The highest among them is located in Rudno and crowned with the ruins of the castle Tęczyn (401.1 m asl). The surface of Tenczyński Ridge is intersected by numerous valleys, the most picturesque in the eastern parts, carved in the base out of Upper Jurassic limestones, as the Sanki Valley with Mnikowski Gorge. Tenczyński Ridge is a tectonic horst, constituting the pra-part of the Olkuska Upland plate, separated from it in the Tertiary by Krzeszowicki Graben. The area of this depression is flat, underlain with soft sediments of the Miocene sea, where deposits of sulphate-saline waters, known from Krzeszowice, were formed.