Horka
General Characteristics
County (administration):
Středočeský kraj
District (town):
Kladno
Village:
Braškov
Cadastre:
Braškov
Map sheets:
12-23 Kladno, 12-233 Unhošť
Accessibility:
no traffic restriction ( by car)
ID:
3785
Geology
Short characteristics of the site:
This locality displays a series of outcrops above a road cut. The outcropes expose a contact between the Neoproterozoic silicites (ůydites) and overlying Cretaceous sediments. The Cretaceous sediments contain carbonate admixture and are fossil-bearing, with foraminifers and sponge spicules, rich in ichnofossils. In places they can ber called spomngiolites. The Cretaceous siltstones sometimes pass even into limestones, often they can be called "opuka". The silicites are fractured, sometimes strongly oxidized. In surroundings blocks of silicites they occur, possibly evidences activity of breaking waves of the Cretaceous sea. The silicites belong to the Neoproterozoic Kralupy-Zbraslav Group, the Cretaceous form part of the Bohemian Cretaceous Basin.
Regional geologic unit:
Bohemian Massif > Cretaceous of the Bohemian Massif > Bohemian Cretaceous Basin > Bohemian Cretaceous Basin - Vltava - Berounka development;
Bohemian Massif > Bohemicum > Barrandien > Barrandien - Paleozoic > Kralupy - Zbraslav Group
Stratigraphy:
Upper Cretaceous, Neoproterozoic
Subject:
geology, stratigraphy, lithology
Geological phenomenon:
lithological boundary, transgression
Genesis:
sedimentary
Rock:
opuka (aranaceous marlstone), lydite
Territorial protection
Level of protection:
Registered interesting geological localities
Conflicts of interests:
road construction
References
- M.Stárková et al. (2014): Vysvětlivky ke geologické mapě 12-233 list Unhošť. - MS Archív ČGS Praha.
Elaboration and Updating
Elaborated by:
Pavel Čáp, 11.09.2014
Updated by:
Kukal Zdeněk, 25.09.2017, Kukal Zdeněk, 26.09.2017
Citation
The database Important geological localities of the Czech Republic: 3785 [online]. Prague: Czech Geological Survey, 1998 [cit. 2023-06-16]. Available from: https:// lokality.geology.cz/3785.
Location in map:
Assessment
Scientifical assesment:
great
Educational assesment:
major
Significance:
supraregional
Representativeness:
middle
Geological importance:
significant study profile, geo-regional value (mapping)
Locality conditions:
poor
You can send information about a change in the status of the site to lokality@geology.cz
