| Title | A mafic-ultramafic cumulate sequence derived from boninite-type melts (Niagara Icefalls, northern Victoria Land, Antarctica) |
| Author | Tribuzio, R.; Tiepolo, M.; Fiameni, S. |
| Author Affil | Tribuzio, R., Universita di Pavia, Dipartimento di Scienze della Terra, Pavia, Italy. Other: Istituto di Geoscienze e Georisorse, Italy |
| Source | Contributions to Mineralogy and Petrology, 155(5), p.619-633, . Publisher: Springer International, Heidelberg - New York, International. ISSN: 0010- 7999 |
| Publication Date | May 2008 |
| Notes | In English. 60 refs. GeoRef Acc. No: 287191 |
| Index Terms | Antarctica--Victoria Land; absolute age; andesites; Antarctica; back-arc basins; basins; boninite; Cambrian; chemical composition; crystal chemistry; cumulates; dates; geochemistry; harzburgite; ICP mass spectra; igneous rocks; intrusions; mafic composition; major elements; mass spectra; melts; metals; mineral assemblages; mineral composition; nesosilicates; Niagara Icefalls; orthosilicates; Paleozoic; peridotites; petrology; plutonic rocks; rare earths; Ross Orogeny; silicate melts; silicates; spectra; terranes; textures; trace elements; U/Pb; ultramafic composition; ultramafics; Victoria Land; volcanic rocks; zircon; zircon group |
| Abstract | The layered sequence from Niagara Icefalls (northern Victoria Land, Antarctica) is related to the Cambrian-Early Ordovician Ross Orogeny. The sequence consists of dunites, harzburgites, orthopyroxenites, melagabbronorites and gabbronorites of cumulus origin. The Mg#PS of olivine, spinel, orthopyroxene and clinopyroxene from these rocks yields positive correlations, thus indicating formation from melts that mainly evolved through fractional crystallisation. The occurrence of inherited zircons dated at 538 Ma indicates that the boninitic melts experienced, at least locally, crustal contamination. The Niagara Icefalls sequence can be related to a regional scale magmatic event that affected the eastern margin of the Gondwana supercontinent in the Middle Cambrian. (mod. journ. abst.) |
| URL | http://hdl.handle.net/10.1007/s00410-007-0261-1 |
| Publication Type | journal article |
| Record ID | 84655 |