Middle ro early late Viséan onset of late orogenic sedimentation in the Intra-Sudetic Basin, West Sudetes: miospore evidence and tectonic

Abstract

The Early Carboniferous fluvial and deltaic sequence of the Intra-Sudetic Basin remained undated until recently, except for a Late Viséan ammonoid fauna in its upper part. Current miospore data indicate that the oldest part of the sequence is not older than the mid Viséan Knoxisporites triradiatus-Knoxisporites stephanephorus biozone of the west European miospore division. This palynological age determination is consistent with the recently obtained Ar-Ar cooling ages of white micas from sheared metamorphic rocks at the NW margin of the basin. This suggests that the rapid late orogenic denudation of the northern and western flanks of the Intra-Sudetic Basin must have started at or shortly after c. 335 Ma.