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Rieger's Path

Magmatic rocks

The Rieger's path is in dense trees on a steep slope just barely visible rock tower Myší skála, which consists of Tertiary basalt rock (olivine nefelinit). Fragments of basalt, as proof youngest volcanic activity, the roll up to Rieger's path.

Volcanic rocks line the path

Basalt is a fine-grained rock that contains minerals such as feldspar (plagioclase), olivine, pyroxene, amphibole, and sometimes dark mica (biotite), and magnetite. Rocks with a low silicon content, such as basalt, gabbro and are called basic. Basic rocks are dark, almost black because they contain the minerals iron and magnesium. Gabbro, which is the path Rieger also located inside the earth cooled slowly. It consists of a low grade intergrowths of feldspar and olivine. Basalt also contains larger crystals of olivine, which occurred in the ground earlier. As the rock is fine-grained, it froze quickly. The basic lavas occurs most often basalt, representing more than 90% of all volcanic rocks. Molten rock created several tens to hundreds of kilometers below the Earth's surface, emerges from the depths of the earth and close to the surface cools, solidifies and creates basalt. Alkaline lavas are poor in silica. Flow more easily and explode rather mildly. Of tectonic movements and sometimes opens the gas pressure in the earth's surface blast hole from which the gas flows, ash, slag and lava that creates a volcano. Molten lava rises surrounding rocks and basaltic vents and creates effusions. Basic lavas also fill cracks that form in the Earth's crust vein. The resulting solid rock filled mainly vents, ash and slag are subject to rapid weathering and waiter. In the same way, was on the earth's surface and basaltic rock suk mouse. It represents the remains of the original chimney that were exposed by erosion.

GPS position

N 50° 37.280', E 15° 18.232'



Geopark UNESCO Český ráj
Jiří Vlasák