Abstract
Metamorphic garnet from the Anápolis-Itauçu Complex (AIC), central Brazil, were investigated by electron microprobe analyses and Mössbauer spectroscopy, in order to contribute on their geological history. The data were further extended by magmatic samples from complex and simple pegmatites, as reported by Eeckhout et al. (2002). Three clear chemical tendencies within garnets from AIC rocks were revealed. From Mössbauer spectroscopy data it is obvious that ferrous iron is present at dodecahedral site. Very small amounts of ferric iron at octahedral site of garnet structure are additionally present in garnets from sample of ultra-high temperature (UHT) granulites from AIC, implying slightly oxidizing conditions during this metamorphicevent. In addition, a higher degree of structural disorder has been discerned in these samples.Keywords: Garnet, petrogenetic indicator, hydroxyl, Mössbauer spectroscopy.
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