In western Sardinia (Italy) two different types of manganese ore occur. The less common type is hydrothermal in origin and it is linked to the calc-alkaline volcanism that affected the Sardinia Corsica Microplate in the Oligocene-early Miocene. This hydrothermal ore occur as stock-work within andesite to rhyodacite lava flows. The most common deposit is hosted within a sedimentary bed, linked to the marine transgression that, since middle Miocene, involved the volcanic area of western Sardinia. It forms the cement of a conglomerate at the base of transgressive bioclastic limestones of Burdigalian age. In both the deposit types pyrolusite is the main Mn-phase. Accessory barite and opal-calcite gangue characterise the hydrothermal ore, whereas hollandite occurs in the sedimentary deposits.
Ba in different Mn ores of Sardinia (Italy): a preliminary study / Sinisi, R; Mameli, Paola; Oggiano, Giacomo; Mongelli, G.. - 1-2:(2010), pp. 331-333. (Intervento presentato al convegno 10th Biennial SGA Meeting of the Society for Geology Applied to Mineral Deposits tenutosi a Townsville (Australia) nel 17-20 August 2009).
Ba in different Mn ores of Sardinia (Italy): a preliminary study
MAMELI, Paola;OGGIANO, Giacomo;
2010-01-01
Abstract
In western Sardinia (Italy) two different types of manganese ore occur. The less common type is hydrothermal in origin and it is linked to the calc-alkaline volcanism that affected the Sardinia Corsica Microplate in the Oligocene-early Miocene. This hydrothermal ore occur as stock-work within andesite to rhyodacite lava flows. The most common deposit is hosted within a sedimentary bed, linked to the marine transgression that, since middle Miocene, involved the volcanic area of western Sardinia. It forms the cement of a conglomerate at the base of transgressive bioclastic limestones of Burdigalian age. In both the deposit types pyrolusite is the main Mn-phase. Accessory barite and opal-calcite gangue characterise the hydrothermal ore, whereas hollandite occurs in the sedimentary deposits.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
