The palynostratigaphic data, although still scarce, allow some considerations on the age of the volcanism and the structural development.
In the north branch of the belt, the felsic and mafic volcanism appears to be mostly of late Famennian age, at least in the studied antiforms, while the mafic intrusions, although with an uncertain age may be younger, possibly emplaced in a post Strunian age. This would suggest that the volcanism has been originated in similar geodynamic conditions (along the same crustal tectonic lineament ?). In the south branch volcanic episodes can reach younger ages even the early Late Viséan. Does this mean that volcanism progressed southward in time, as suggested by Oliveira, 1990 (?). Further research is still needed to reach a definitive conclusion.
The structure of the Albernoa Antiform is schematically depicted in Figure 10. It shows the lithologies of the PQ Group and the VSC in conformable stratigraphic order, thrusted by shales, quartzites and quarzwackes ascribed to the PQ Group. The thrust was generated during the first NE-SW compressional episode of latest Viséan age and later refolded in the same sense during the Upper Carboniferous (post Moscovian) time.
The Serra Branca Antiform shows a similar tectonic style with the VSC conformably overlain by the Freixial Fm. and the latter thrusted by the PQ Group and VSC lithologies (Figure 11).
The structure of the Mina de São Domingos Antiform has, in general, the same tectonic style. However, in detail it is complex and the existing data preclude, for the moment, any definitive structural interpretation.
These structural interpretations, now supported by palynostratigraphic age determinations, confirm previous tectonic modelling for the Portuguese part of the Pyrite Belt (Ribeiro et al., 1983; Oliveira, coordinator 1988; Silva et al., 1990; Oliveira and Silva 1990).
