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the Basal Units (
Díez Fernández et al., 2010; Fuenlabrada et al., 2010
).
The Upper Unitsmay be dividedinto two groupsaccordingto metamor-
phiccriteria: an uppermostsection with intermediate-P metamorphism
ranging from the chlorite zone to the granulite facies, and a lower
section showing HP and high-T (HT) metamorphism dated at c. 400
–
390 Ma (
Ordóñez Casado et al., 2001; Fernández-Suárez et al., 2007
).
The latter metamorphic event reachedUHP conditionsin other domains
of the Variscan belt (
Lardeaux et al., 2001
). The main tectonothermal
events recorded in the uppermost section are Cambrian in age and
were probably developed in response to the accretionary dynamics of
the peri-Gondwanan arc system (
Abati et al., 1999, 2007; Díaz García
et al., 2010
).
(b)
(a)
Fig.2.
(a)GeologicalmapoftheallochthonouscomplexesoftheNWIberianMassif(Galiciaregion),and(b)compositecrosssection,showingthedistributionandgeneralstructureofthe
terranes involved in the Variscan suture. The location and name of the most representative units are indicated.
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8. TWO STAGE COLLISION
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