1. Structure of a Variscan migmatite-granite transition zone (N Sardinia, Italy).
- Author
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De Luca, M., Ruberti, N., Oggiano, G., Rossi, Ph., Pascucci, V., and Casini, L.
- Subjects
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SHEAR zones , *GEOLOGICAL mapping , *GEOLOGICAL maps , *XENOTIME , *GRANODIORITE , *IGNEOUS intrusions , *AMPHIBOLITES - Abstract
This paper presents the structural map of the Barrabisa Complex, an E-W ribbon-like migmatitic massif exposed in the northern part of Sardinia. The migmatites consist of metatexites and diatexites with variable melt proportion, grading in the central part of the complex to a foliated peraluminous granodiorite. Xenotime/monazite dating indicates that the foliated granodiorite pluton emplaced in upper Carboniferous times (≈307–313 Ma) within a narrow E-W ductile top-to-the east shear zone cutting through a Variscan high-grade metamorphic basement composed of orthogneisses, metasedimentary-derived migmatites and subordinate amphibolites. Field geological mapping, coupled with structural and micro-structural analysis, allowed us to distinguish the granodioritic pluton and three metamorphic units characterized by variable melt to protholith ratio, that represent a continuous transition from metatexite to diatexite with high melt concentration, to foliated granodiorite. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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