Abstract

Turbulent episodic events are responsible for numerous short term reversals or interruptions of the Famennian regressive megasequence in the Ardenne-Rhenish Massif.

Most of these events were triggered by epeirogenic movements related to rejuvenated basement faults in the distal part of the Variscan orogen. On one hand, eustatic sea level changes are shown by erosion gaps, black shales and reef episodes, whereas evaporites and paleosoils point to fluctuations of a semi-arid climate in the then southern hemisphere.

On the other hand, oolitic ironstones, turbidites, bentonites, marine red beds, ball-and-pillow structures and high energy tempestites are evidence of tectonic instability related to intermittent block faulting of the studied area.

The interaction between this block faulting and the deflected Western Boundary Current, determined the complex depositional history of the Upper Famennian Condroz Sandstone belt, south of the London-Brabant Massif.