Proposal of lithostratigraphy for the České středohoří Mts. volcanics

 

Authors: Cajz V

Published in: Bulletin of Geosciences, volume 75, issue 1; pages: 7 - 16;

Keywords: Tertiary volcanics, the České středohoří Mts., lithostratigraphy,

full text (PDF, 4.97 MB)

Export to RIS

 

Abstract

This contribution proposes the lithostratigraphy of the Tertiary volcanosedimentary complex of the České středohoří Mts. The superficial volcanic products of the České středohoří Mts. are divided into three formations. The Ústí Fm. (36.1 - 25.5 Ma) includes basanites and their concomitant volcaniclastics including fossiliferous sediments, and represents products of early rift development - the filling of a rift valley. The Děčín Fm. (30.8 - 24.7 Ma) is composed of trachybasalts and trachybasaltic resedimented tuffs, which are erosional relics of a composite volcano - the product of more advanced stage of rift evolution. The Dobrná Fm. (24.0 - 19.3? Ma), represented by basanitic lavas, was produced as a result of a possible remobilization of the magma chamber. All these formations represent one volcanic cycle (uppermost Eocene - lowermost Miocene, with a maximum in the Oligocene). The basanitic intrusions penetrating the Most Fm. sediments are comprised in the fourth lithostratigraphic unit, the Štrbice Fm. (13.4 - 9.0? Ma). It is most probably a product of a younger volcanic cycle (Middle Miocene) and extends to the Most Basin, too. The Ústí Fm is largely correlated with the Střezov Fm. of the Most Basin.