Matejkovský skalný (kamenný) prúd predstavuje ojedinelú ukážku sutoviska v priestore velkofatranského kryštalinika. Nachádza sa v nadmorskej výške cca. 1000m. Velká Fatra je zväcša budovaná druhohornými sedimentmi krížnanského a chocského príkrovu a kryštalické horniny, predovšetkým žuly vystupujú len zriedkavo predovšetkým v oblasti Lubochnianskej doliny a masívu Smrekovice. Hornina je rozrušená do kamenných blokov velkých od niekolko desiatok cm do 1 metra. Jedná sa o žulu až granodiorit. Casté sú žilky pegmatitov. Matejkovský skalný prúd má z prírodovedného hladiska podobný význam ako napr. Kamenné more vo Vyhniach (na ryolitoch).
GRANIT alebo ZULA je hlbinná vyvretá hornina, ktorej podstatnými minerálnymi súcastami sú draselný živec, plagioklas, kremen a biotit. Súhrnný názov pre granit a jemu podobné horniny (granodiorit a kremitý diorit) je granitoid. Granitoidy od seba nemožno bez znalosti minerálneho zloženia volným okom presne odlíšit.
GRANODIORIT je intruzívna hornina prechodného zloženia medzi granitom (žulou) a dioritom. Patrí do skupiny granitoidov. Tieto horniny, od ktorých je makroskopicky tažko rozlíšitelný sú si všetky velmi podobné.
Prírodný výtvor je dobre viditelný už z cesty. Hoci je velkostou podstatne menší ako vysokohorské sutoviská Nízkych a Vysokých Tatier, ojedinelý je jeho výskyt v pásme pod hornou hranicou lesa v polohách kde sa v ladových dobách nepredpokladalo zvlášt intenzívne erozívne pôsobenie ladu.
*** Súradnice vás zavedú na miesto, kde môžete zaparkovat vozidlo. Odtialto je kamenný prúd dobre viditelný na lavej strane potoka, vzdialený cca 50 metrov. ***
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4. Dobrovolne: kazdé zaujímavé foto z lokality potesi
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[EN] Location Matejkovský stony stream is located in National Park Great Fatra on the 5th mile on the left side of the valley Vyšné Matejkovo. It covers an area 8.60 ha. In 1986 the site was declared a natural monument as a way to protect granite stony stream, which presents an example of cuboid granite fracturing and frost weathering.
Matejkovský stony (rock) stream is a unique example of a debris in the area of Great Fatra´s crystalline. Located at an altitude of approx. 1000 m. Great Fatra is largely built of Mesozoic sediments, Krížna and Choc ´s overthrust. Crystalline rocks, mainly granite appears only rarely in the particular field of Lubochnianska valley and the Smrekovica massif.
The rock eroded into large stone blocks from a few tens of centimeters to 1 meter. It can be granite to granodiorite. Pegmatites veins are also common. Matejkovský stony stream from the natural light has a similar meaning as such rhyolitic Stone-block Sea in Vyhne.
GRANITE is a common and widely occurring type of intrusive, felsic, igneous rock. Granites usually have a medium- to coarse-grained texture. Occasionally some individual crystals (phenocrysts) are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic texture is sometimes known as a porphyry. Granites can be pink to gray in color, depending on their chemistry and mineralogy. By definition, granite is an igneous rock with at least 20% quartz by volume.
GRANODIORITE is an intrusive igneous rock similar to granite, but containing more plagioclase than potassium feldspar. Officially, it is defined as a phaneritic igneous rock with greater than 20% quartz by volume where at least 65% of the feldspar is plagioclase. It usually contains abundant biotite micaand hornblende, giving it a darker appearance than true granite. Mica may be present in well-formed hexagonal crystals, and hornblende may appear as needle-like crystals.
The monument is clearly visible from the road. The size is considerably smaller than alpine debrises of Low and High Tatras. Its presence is unique in the zone below the upper limit of the forest.
*** The coordinates take you to the place, where you park the vehicle. From there, the stony stream is easily visible on the left side of the creek, cca 50 meters. ***
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1. Observe the shapes of rocks and describe by your own words the cuboid granite fracturing.
2. Describe the visible signs of the frost weathering on the rocks.
3. Describe the process of frost weathering.
4. Optional: Interesting photo of the site will enjoy.
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Zdroje/Information sources : www.mineraly.sk http://sk.wikipedia.org http://en.wikipedia.org