Age determination of Ordovician magmatism in NE Sardinia and its bearing on Variscan basement evolution. (Articolo in rivista)

Type
Label
  • Age determination of Ordovician magmatism in NE Sardinia and its bearing on Variscan basement evolution. (Articolo in rivista) (literal)
Anno
  • 2005-01-01T00:00:00+01:00 (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi
  • 10.1144/0016-764904-103 (literal)
Alternative label
  • Helbing H.; Tiepolo M. (2005)
    Age determination of Ordovician magmatism in NE Sardinia and its bearing on Variscan basement evolution.
    in Journal of the Geological Society (Lond.); Blackwell Publishing, Oxford (Regno Unito)
    (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori
  • Helbing H.; Tiepolo M. (literal)
Pagina inizio
  • 689 (literal)
Pagina fine
  • 700 (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume
  • 162 (literal)
Rivista
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali
  • 11 (literal)
Note
  • ISI Web of Science (WOS) (literal)
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni
  • Institut fur Geowissenschaften, Universitat Tubingen, Sigwartstrasse 10, 72076 Tubingen, Germany CNR-Istituto di Geoscienze e Georisorse-Sezione di Pavia, Via Ferrata 1, 27100 Pavia, Italy (literal)
Titolo
  • Age determination of Ordovician magmatism in NE Sardinia and its bearing on Variscan basement evolution. (literal)
Abstract
  • A newly discovered pre-Variscan cover-basement relationship in NE Sardinia is defined by differences in structural and metamorphic histories. The oldest metamorphic fabrics in the basement are absent from a series of metaplutons that are inferred to be comagmatic with metavolcanic rocks in the cover. Cover and basement are further distinguished by contrasting metapelite compositions. Superimposed metamorphism is represented by pre-Variscan garnet and Variscan plagioclase porphyroblasts that appear in the field as a 'mixed' garnet þ albite zone. In situ U-Pb zircon dating of meta-igneous rocks from cover and basement by laser-ablation inductively coupled plasma-mass spectrometry gives ages of 458 +/- 7 Ma for the Tanaunella orthogneiss, 456 +/- 14 Ma for the Lode` orthogneiss, and 474 +/-13 Ma for the Lula porphyroid. The internal Sardinian Variscides thus incorporate a mid-Ordovician magmatic belt developed upon an older basement; correlation is proposed with a tectonostratigraphic domain that is at present exposed in the Alps. Within the mid-Ordovician peri-Gondwanan realm, the internal Sardinian Variscides appear to have developed along an active margin, whereas the foreland correlates with the Ibero-Aquitaine domain and is related to the evolution of a passive margin during rifting and detachment of Avalonia to form the Rheic Ocean. (literal)
Editore
Prodotto di
Autore CNR
Insieme di parole chiave

Incoming links:


Prodotto
Autore CNR di
Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#rivistaDi
Editore di
Insieme di parole chiave di
data.CNR.it