Mariánská Skála (Mariánská hora; Marienberg), Ústí nad Labem, Ústí nad Labem District, Ústí nad Labem Region, Czech Republici

Regional Level Types
Mariánská Skála (Mariánská hora; Marienberg)	Quarry (Active)
Ústí nad Labem	Municipality
Ústí nad Labem District	District
Ústí nad Labem Region	Region
Czech Republic	Country

Active quarry in an irregular phonolite laccolith which penetrated into different levels of the Cretaceous sediments along a pre-existing tectonic structure in the Upper Oligocene (26 Ma). Later it was tectonically modified and intersected by the Labe River to form Mariánská hora Hill and Kamenný vrch Hill. The laccolith is formed by miaskitic natrolite sodalite phonolite passing into analcime sodalite phonolite in marginal parts of the body.

Located east of Ústí nad Labem.

Mariánská skála or Mariánský vrch (German Marienberg) is a significant, even dominant element in the center of Ústí nad Labem. It rises on the left bank of the river Elbe to a height of 265 m above sea level, ie about 120 m above the river level. Together with the opposite right-bank rock Kramolna, it forms the so-called Ústí Gate. At the end of the 20th century, a new bridge over the Elbe was built on the site of this Ústí Gate. It is a very important deposit of various rare minerals.

The hill is located about 200 m east of the city centre.

The existence of a long-term active quarry contributed to the popularity of Mariánská skála as an important mineralogical locality.

From a geological point of view, the rock is formed by sodalite-natrolithic laccolith. Originally, it was a subsurface magmatic body, which was exposed by erosion of the river (Elbe) stream. The composition of the rock is so specific that it gave rise to the special name marienbergite.

The quarry is a rich deposit of zeolite minerals, especially unique examples of natrolite, which makes up 40% of the rock. In addition to natrolite, there are apophyllite, calcite, wad, analcime, thomsonite and hyalite, as well as contact metamorphic minerals of the mantle shell - wollastonite, Ti-garnet and hydrogrossular (called hibschite). In the top parts of Mariánská hora, at a height of 120 m above today's level of the Elbe, a relic of the original river terrace from the period at the turn of the Tertiary and Quaternary has been preserved. The tooth of the octopus Archidiscodon meridionalis from the Pliocene period was found in these sediments, which are 3 meters thick.

Other Databases

Wikipedia:	https://cs.wikipedia.org/wiki/Mari%C3%A1nsk%C3%A1_sk%C3%A1la
Wikidata ID:	Q12035560

Other Regions, Features and Areas containing this locality

References