A review of northern Victoria Land ultramafic xenoliths, collected and studied over more than thirty years, was carried out. More than 200 samples were gathered and characterised in a coherent and comparative manner, both for mantle-derived and cumulate xenoliths. Almost 2,000 analyses of major elements and more than 300 analyses of trace elements of in situ and separated olivine, pyroxenes, amphibole, spinel and glass were taken into consideration. Particular attention was devoted to mantle lithologies in order to emphasize the composition and the evolution of this portion of the sub-continental lithosphere. The three main localities in northern Victoria Land where mantle xenoliths were found, i.e. Mount Melbourne (Baker Rocks), Greene Point and Handler Ridge, over a >200 km distance, were described and compared with the ultramafic xenoliths in three other localities, Harrow Peaks, Browning Pass and Mount Overlord, which are mainly cumulate in nature. Altogether, these data enabled us to reconstruct a long evolutionary history from old depletion, to most recent refertilisation and metasomatic events for this large sector of the northern Victoria Land sub-continental lithospheric mantle.
Nature and evolution of the northern Victoria Land Lithospheric Mantle (Antarctica) as revealed by ultramafic xenoliths
Giacomoni, Pier Paolo;
2021-01-01
Abstract
A review of northern Victoria Land ultramafic xenoliths, collected and studied over more than thirty years, was carried out. More than 200 samples were gathered and characterised in a coherent and comparative manner, both for mantle-derived and cumulate xenoliths. Almost 2,000 analyses of major elements and more than 300 analyses of trace elements of in situ and separated olivine, pyroxenes, amphibole, spinel and glass were taken into consideration. Particular attention was devoted to mantle lithologies in order to emphasize the composition and the evolution of this portion of the sub-continental lithosphere. The three main localities in northern Victoria Land where mantle xenoliths were found, i.e. Mount Melbourne (Baker Rocks), Greene Point and Handler Ridge, over a >200 km distance, were described and compared with the ultramafic xenoliths in three other localities, Harrow Peaks, Browning Pass and Mount Overlord, which are mainly cumulate in nature. Altogether, these data enabled us to reconstruct a long evolutionary history from old depletion, to most recent refertilisation and metasomatic events for this large sector of the northern Victoria Land sub-continental lithospheric mantle.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
