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1
I
Introduction
1.1. Introduction to the PhD thesis
1.2. Article summary
1.1. Introduction to the PhDThesis
This PhD thesis explores the generation, the
sources and the development of a high-grade
metamorphic terrain involved in the Variscan
orogen, the mountain belt formed when
the last supercontinent, Pangea, assembled.
When continents are pieced together to form
supercontinents, the oceanic crusts that separate
them are consumed by subduction, a process
capable of forming extensive volcanic arc systems.
When the continents finally collide, their margins
are subducted to great depths and mountain
belts are developed, favouring a scenario where
extreme deformations and high or even ultra-
high grade metamorphism can take place. The
studied terrain attained very high deformation
when the margins of the continents started to
interact at the initial stages of their assembly, as
well as during the intense decompression attained
when the terrain exhumed after pronounced
continental subduction.
High-grade terrains contain very valuable
information about the history of the orogen in
which they were formed, because they register
several processes around the cores of the belt
itself. But on the other hand, this information
is cryptic and difficult to decipher because
each process blurs the information recorded