Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Petrography of selected amphibole lamprophyres and associated intrusions in the NW part of the Barrandian Neoproterozoic (Rakovník area)
Abstract
The Neoproterozoic rock sequences in the NW part of the Barrandian were intruded by lower Palaeozoic amphibole (kaersutite) lamprophyres of different types. Lamprophyres with "appinitic textures" and related microdioritic dykes genetically connected with small stocks of amphibole diorites, meladiorites and hornblendites are more widespread. The lamprophyres of this suite have two discrete anhedral feldspars in the groundmass (albite and K-feldspar) as well as magnetite as a typomorphic accessory mineral. The second type, less widespread, represents amphibole lamprophyres spatially connected with quartz diorite to granodiorite intrusions of the Kožlany zone. These dykes have irregularly zoned (albite-andesine) plagioclase laths in the groundmass and ilmenite as a typomorphic accessory mineral. The mineral chemistry of lamprophyric rocks was determined using the electron microprobe.
