Carosi, Rodolfo and Di Pisa, A. and Iacopini, David and Montomoli, Chiara and Oggiano, Giacomo (2004) The Structural evolution of the Asinara Island (NW Sardinia, Italy). Geodinamica Acta, Vol. 17 (5), p. 309-329. ISSN 0985-3111. eISSN 1778-3593. Article.
Full text not available from this repository.
The metamorphic basement of the Asinara island represents a key area of the Sardinia Variscan segment, because it displays an almost complete cross-section through the inner part of the Sardinia Variscan belt, where different tectono-metamorphic complexes have been juxtaposed along narrow belts of high-strain concentration. Detailed field mapping coupled with preliminary studies on the structural and metamorphic features of this small island, allow to draw a better picture of the structural frame issued from the Variscan collision in the inner zone of the belt. Three deformation phases related to crustal thickening in a compressive and transpressive, partitioned tectonic regime, followed by a later phase of extensional deformation have been recognised. In spite of a general HT/LP metamorphic overprint, linked to the post-collisional deformation phases, a relic Barrovian zoneography is still detectable. The Barrovian assemblages are preto syn-kinematic with respect to the D2 deformation phase, and pre-date the third, contractional tectonic event. The HT/LP assemblage indicates a static growth of weakly deformed by the last deformation events. The complex geometry of the fabric associated to the D2 and D3 deformation events suggests an heterogenous deformation history with a monoclinic geometry characterized by switching of the stretching lineation orientation and a contrasting sense of displacement, probably controlled by a northward partitioned pure shear.
I documenti depositati in UnissResearch sono protetti dalle leggi che regolano il diritto d'autore
Repository Staff Only: item control page