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IV
The eclogite facies gneisses
of the Cabo Ortegal Complex
4.1. Introduction
4.2. Partial conclusions
4.3. Article
4.1. Introduction
This article deals with the tectonothermal
evolution of the eclogite facies gneisses (Banded
Gneisses) of the Cabo Ortegal Complex. It
shows a detailed description of the macroscopic
and microscopic features of these gneisses,
and two detailed cross-sections performed in
excellent exposures on the Cantabrian coast
allowing a clear understanding of the lithological
constitution and deformations affecting the unit.
This work represents the starting point for the
following chapters, as it shows the constitution of
the main formation studied and a discussion of its
tectonothermal evolution, from the knowledge
extracted from previous works and from the
structural features described. It is also argued
and proposed a model for the exhumation of the
terrane in which the formation is included.
4.2. Partial conclusions
The high-P conditions that affected parts of
Upper Allochthon terrane indicate that they once
constituted a subduction complex, developed
on a continental or a transitional thinned
continental margin containing thick sedimentary
series.
The deep subduction (D1 event) that
this margin underwent necessarily implies the
existence of a colliding retro-continent. The