Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Variolite in the borehole Np-1 Nepasice in Eastern Bohemia
Abstract
An over 2 km deep structural borehole penetrating in Eastern Bohemia the sedimentary cover of Upper Cretaceous, Lower Carboniferous and Devonian continued in the lenghth of almost 1200 m through a slightly metamorphosed volcanosedimentary sequence the age of which remained uncertain. During the revision of bore-cores, variolites have been found within the volcanic (spilitic) sectors of it. On the actual surface of the Czech Republic, such texture is known exclusively from Neoproterozoic of Bohemian Massif. This finding supports opinions, that the pre-Devonian part of the borehole profile represents the analogy of the Central Bohemian (Barrandian) type Neoproterozoic, affected by a pre-Variscan tectonometamorphic event.
