General Characteristics

County (administration): Plzeň Region
District (town): Rokycany
Cadastre: Třebnuška - lom
Map 1 : 50 000 (sheet No): 1232, 12323
Geological region: Barrandien Palaeozoic; Blanice Furrow
Accessibility: - special entry permit necessary (military area, quarry, private land)
Technical object: guarry
Excursion locality: yes
ID : 3765

Geology

Short characteristics of the site: Great active quarry in intrusive ryolite body. Rock is crystalline, with phenocrysts of quartz and feldspar. Abundant xenolits of underlying rocks (Cambrian sedioments, andesite). Various dykes of lamprophyric rocks cut the massive in two oblique directions. Ryolite belongs to the Upper Cambrian (Furong) Křivoklát-Rokycany comples, dykes are younger (Ordovician?).
Regional geologic unit: Bohemian Massif - crystalline complex and pre-Variscian Palaeozoic - Bohemicum (Central Bohemian region) - Barrandien
Stratigraphy: paleozoikum - kambrium - svrchní kambrium
Subject: volcanology
Geological phenomenon: intrusion, dyke
Genesis: volcanic
Rock: rhyolite, lamprophyre

Territorial conservation

Level of protection: Registred geological localities suggested to protection in Protected landscape area
Protection of a geol. phenomenon: B - Geological phenomenon is the reason for a recommendation to the protection
Part of LEPA (Large-size especially protected areas): CHKO (Protected landscape area) - Křivoklátsko
Part of the Geopark: Barrandien
Conflicts of interests: exploitation

References

Vorel T. et.al. (2014): Vysvětlivky ke geologické mapě 12-323 list Podmokly. - MS Archív ČGS Praha.

Elaboration and Updating

Elaborated by: Hradecký Petr, 02.04.14

Citation

The database Significant geological localities of the Czech Republic: 3765 [online]. Prague: Czech Geological Survey, 1998 [cit. 2024-05-04]. Available from: http:// lokality.geology.cz/3765.

Location in map: