THE OH COMPONENTS IN GARNETS FROM DIFFERENTGEOLOGICAL ENVIRONMENTS: P-T AND BULK COMPOSITION CONSTRAINTS

Autor:	Eddy De Grave, Sigrid Griet Eeckhout, Danielle Piuzana, Cristiane Castañeda
Rok vydání:	2013
Předmět:	Pharmacology Octahedron Garnet petrogenetic indicator hydroxyl Mössbauer spectroscopy Metamorphic rock Oxidizing agent Analytical chemistry Mineralogy Electron microprobe Granulite Geology Pegmatite Ferrous
Zdroj:	Revista Geonomos; Geonomos-v.17 n. 1 (2009)
ISSN:	2446-6964 0104-4486
Popis:	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.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c3e3956c7c31685395f765d759d55b1d https://doi.org/10.18285/geonomos.v17i1.82 Zobrazit plný text záznamu