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Besedice Rocks

Mushroom rocks

Mushroom rock is shape of mesorelief in the top parts of rocks. It is spherical, ovate or pyramidal. Mushroom rock occurs typically in sandstones disaggregated set of vertical cracks on individual pinnacles or smaller rocks. These are formations created on the edge platforms, ridges or rock wings. The emergence Boletaceae shapes in temperate climates important horizontal broken sandstone massif. The emergence of hats here is by the presence of horizontal positions ferric sandstone and conglomerate or positions imbued with siliceous cement. This means that the sandstone is stronger and more resistant to erosion caused by water and rain. Narrowed the rocks (foot) are, however, linked to the level of erosion surfaces that are composed of less resistant sandstone, usually with a clayey and kaolinitickým sealant. Increased susceptibility to erosion is not caused only by the chemical composition of sandstone, but for example, or the presence of intense bioturbací valounového material in the rock. The narrowing of the legs can also participate in a higher frequency of horizontal or slightly inclined cracks.

The conditions for the emergence of rock mushrooms thus formed already in the process of sedimentation on the bottom of the sea in the Cretaceous Mesozoic and subsequently after the sandstone diagenesis of sediments (ie, the sum of processes changing mineral composition, structure and texture of sediment). These processes sandstone horizontally articulated with the positions of the different resistance to weathering. The resulting mushroom shape is the result of unequal rates of weathering at different height levels fissures limited rock block, which acts on exogenous factors.

Mushroom rock

Další případ skalního hřibu Hodánka

Another case of mushroom rock Hodánka

GPS position

N 50° 37.800', E 15° 11.967'



Geopark UNESCO Český ráj
Jiří Vlasák