New data implying crustal activation of Eastern Avalonia along
the
Anglo-Brabant fold belt are
presented. Late Ordovician subduction-related magmatism in East Anglia
and
the Brabant Massif, coupled
with accelerated subsidence in the Anglia Basin and in the Brabant Massif
during Silurian time, indicate a
foreland basin development. Final collision resulted in folding, cleavage
development and thrusting during
the mid-Lochkovian to mid-Eifelian. In the southeast of the Anglo-Brabant
fold
belt, Acadian deformation
produced basin inversion and the regional antiformal structure of the Brabant
Massif. The uplift, inferred
from the sedimentology, petrography and reworked palynomorphs in the Lower
Devonian of the Dinant
Synclinorium is confirmed by illite crystallinity studies. The tectonic
model
discussed implies the presence
of two subduction zones in the eastern part of Eastern Avalonia, one along
the
Anglo-Brabant fold belt and
another under the North Sea in the prolongation of the North German–Polish
Caledonides.