The origin of Na-alkaline lavas revisited: new constraints from experimental melting of amphibole-rich metasomes+lherzolite at uppermost mantle pressure

Објеката

Тип

Рад у часопису

Верзија рада

објављена верзија

Језик

енглески

Креатор

Tobias Grützner, Dejan Prelević, Jasper Berndt, Stephan Klemme

Извор

Contributions to Mineralogy and Petrology

Датум издавања

2023

Сажетак

We present a new experimental dataset for reaction experiments between natural amphibole-clinopyroxene metasomes (hornblendite) and synthetic lherzolite that produced Na-rich alkaline melts. Experiments were conducted at 1, 3 and 4 GPa and 1000–1300 °C. The generated melts range from foidite over basanite to phonotephrite. At 1 GPa between 1000 and 1100 °C amphibole decompression-breakdown products generate a phonotephritic melt. Among the breakdown components rhönite was found to be stable up to 1100 °C and 1 GPa. At 3 and 4 GPa the melt compositions are affected by phlogopite melting and shift to more foiditic compositions. We find that the melting of hornblendites and the reaction of the melt with the lherzolite produce wehrlitic residues with different olivine/clinopyroxene ratios. Wehrlite formation does not always require separate metasomatic processes but can be a direct by-product of alkaline volcanism. We applied a metasome melting model to the magmas of the Kula volcanic province, Turkey, and show that at 1 GPa basanite melts and phonotephrite melts cover the whole range of known Kula lava compositions. The Kula lava compositional trend can be therefore generated by basanite-phonotephrite melt mixing. A comparison of high-pressure (3–4 GPa) melts with natural nephelinite data shows overlap with many major, minor, and trace elements but differences in SiO2, FeO, and TiO2 argue that the natural nephelinite data do not represent primary metasome melts.

Број

178

почетак странице

73

doi

10.1007/s00410-023-02052-6

issn

1432-0967

Subject

аlkalni vulkanizam, еksperimentalna petrologija, кersutit, Kula vulkan, хornblendit, metasomatizam omotača

alkaline volcanism, experimental petrology, kersutite, Kula volcano, hornblendite, mantle metasomatism

Шира категорија рада

M20

Ужа категорија рада

М21

Права

Отворени приступ

Лиценца

All rights reserved

Формат

.pdf

Скупови објеката

Дејан Прелевић

Radovi istraživača

Медија

s00410-023-02052-6.pdf

Tobias Grützner, Dejan Prelević, Jasper Berndt, Stephan Klemme. "The origin of Na-alkaline lavas revisited: new constraints from experimental melting of amphibole-rich metasomes+lherzolite at uppermost mantle pressure" in Contributions to Mineralogy and Petrology (2023). https://doi.org/10.1007/s00410-023-02052-6

This item was submitted on 14. јануар 2025. by [anonymous user] using the form “Рад у часопису” on the site “Радови”: http://romeka.rgf.rs/s/repo