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Žula v Geoparku

Flour Sacks

You are below the nature monument “Moučné pytle” (“Flour Sacks”). The surroundings are built by medium to coarse grained two-mica granite of the so-called Kfely type. The Kfely granite forms a peculiar body between Loket and the Teplá valley south of Karlovy Vary. Within frame of the granite pluton it occupies superior position to the Loket granite; the contact is subhorizontal and so in the landscape relief it follows the contour lines. The Kfely granite differs by a relatively high content of white mica (muscovite) from typical “mountain granites” (“gebirgsgranite”, Older Intrusive Complex) and is regarded as a transition to the younger „erzgebirgsgra­nites“.

Due to effects of erosion and weathering processes the granite forms pictorial rock shapes in many places, whose beauty can be admired mainly in the deep valley of Ohře river. Somewhat aside is the natural sight Moučné pytle, which can be found west of the settlement Cihelny. The rock formations with length of 500 m are located in elongated summit of Jelení vrch (643.6 m), which offers a fascinating outlook to northwest. The locality is an outstanding example of the so-called pack-like joint, which is manifested in formation of flat, round and as if on each other stacked boulders (hence the name „Moučné pytle“, which means “flour sacks”).

These forms originated by advanced weathering of granite along natural jointing planes. The rainwater penetrates into them, slowly dissolves less resistant minerals and in winter months enlarges its volume. More processes ally to that, like e.g. thermal tension between grains of individual minerals as a consequence of rock's heating by sun radiation, or chemical influence of organisms. The rock in these places disintegrates into individual mineral grains, which crumble away gravitationally and are carried away by rainwater and wind – fissures gradually widen and edges of blocks round. The highest rock tower has height 7 m, and in its top evolved three rock basins, which however can be admired only by individuals with good climbing abilities.

GPS position

N 50° 10.918', E 12° 49.525'
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