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3. GEOLOGICAL FRAMEWORK
Fig. 8.
Thin-section images of the high-pressure lithologies from (
a-f
) the Malpica-Tui and (
g
) Órdenes complexes. Blues-
chist-facies rocks from the Ceán Unit: (
a
) low-Ca metapelite from the upper structural levels displaying highly pleochroic
chloritoid porphyroblasts; (
b
) Glaucophane-chloritoid-bearing garnet micaschist interbedded with the metabasic rocks; (
c
)
Retrogressed blueschist with pseudomorphs after lawsonite located at the base of the unit. Eclogites from the Malpica-Tui
Unit: (
d-e
) Honeycomb textures in eclogites including garnet, omphacite, rutile, clinozoisite, and white mica; (
f
) A later ge-
neration of poikiloblastic glaucophane is occasionally observed. Eclogites from the Agualada Unit: (
g
) retrogressed eclogite
displaying primary honeycomb texture formed by omphacite (later transformed to a symplectitic aggregate) surrounding
garnet. The eclogitic assemblage is formed by garnet, omphacite, rutile, and quartz. Post-eclogitic parageneses in the amphi-
bolite-facies conditions include hornblende, plagioclase and epidote.