Trace-element partitioning between plagioclase, alkali feldspar, Ti-magnetite, biotite, apatite, and evolved potassic liquids from Campi Flegrei (Southern Italy)
| Autor: | Vincenzo Brescia Morra, Lorenzo Fedele, Leone Melluso, Michele Lustrino, Riccardo Vannucci, Alberto Zanetti |
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| Přispěvatelé: | Fedele, Lorenzo, Lustrino, M., Melluso, Leone, Morra, Vincenzo, Zanetti, A., Vannucci, R. |
| Rok vydání: | 2014 |
| Předmět: |
Incompatible element
biology Ti-magnetite Trace element Partition coefficients Trachyte Mineralogy Biotite LA-ICP-HRMS engineering.material Sanidine biology.organism_classification Geophysics Geochemistry and Petrology Campi flegrei Plagioclase engineering Apatite Alkali feldspar Geology Lile alkali feldspar apatite partition coefficients plagioclase geochemistry and petrology geophysics |
| Zdroj: | The American mineralogist 100 (2015): 233–249. doi:10.2138/am-2015-4995 info:cnr-pdr/source/autori:Fedele L.; Lustrino M.; Melluso L.; Morra V.; Zanetti A.; Vannucci R./titolo:Trace-element partitioning between plagioclase, alkali feldspar, Ti-magnetite, biotite, apatite, and evolved potassic liquids from Campi Flegrei (Southern Italy)/doi:10.2138%2Fam-2015-4995/rivista:The American mineralogist/anno:2015/pagina_da:233/pagina_a:249/intervallo_pagine:233–249/volume:100 |
| ISSN: | 0003-004X |
| Popis: | Partition coefficients (Min/L D ) for a series of geochemically relevant elements have been calculated from combined EMP/LA-ICP-HRMS analyses of plagioclase, alkali feldspar, Ti-magnetite, biotite, apatite, and trachytic/trachyphonolitic melt pairs in selected Campi Flegrei rocks. Pl/L D and Kfs/L D values are generally very low for most of the trace-elements but Sr, Ba, and Eu. Kfs/L D for the latter elements record a systematic increase as the melt composition changes from trachyte to trachyphonolite, likely due to increasing structural compliance of the sanidine in the trachyphonolites related to larger Na/K values. Conversely, Kfs/L D values for transitional, highly charged incompatible elements (e.g., LREE) decrease from trachyte to trachyphonolite, possibly in response to the decrease of melt polymerization. Min/L D values for titanomagnetite generally decrease with the increasing melt evolution, the highest values being those measured for Ti, V, and Sc. Ti, Ba, Sc, Rb, Nb, Ta, and V are compatible in biotite in equilibrium with trachytic melt, whereas Cs, Sr, and Pb are incompatible and REE are strongly incompatible, as supported by the extremely low Bt/L D Y (0.003–0.008). Partition coefficients for apatite and trachyphonolitic glass pairs are high for Sr, REE (particularly MREE), and Y, large for Th, U, and V, generally low for HFSE, and variable for other LILE. The comparison of measured Min/L D values for Campi Flegrei trachytes/trachyphonolites with other sets of partition coefficients reported in literature for evolved systems suggests that a reliable data set for magma evolution modeling requires: (1) a thorough preliminary selection of natural samples; (2) the adoption of accurate microanalytical techniques; (3) the direct measurement of Min/L D values for each specific melt composition. |
| Databáze: | OpenAIRE |
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