High temperature corrosion of olivine phenocrysts in Pliocene basalts from Banat, Romania

Autor(en)
Cornelius Tschegg, Theodoros Ntaflos, Franz Kiraly, Szabolcs Harangi
Abstrakt

Pliocene trachy-basalts from the eastern Pannonian Basin in Romania were studied to re-evaluate their petrogenesis and establish a new model for their eruption characteristics. Bulk major and trace element concentrations, as well as Sr and Nd radiogenic isotope ratios confirm their OIB type signature, totally unaffected and unrelated to precursor subduction activities in the Carpatho-Pannonian region. Late stage magmatic high temperature corrosion of olivine phenocrysts was analyzed in detail, using high-resolution electron-microprobe techniques. The data indicate that corrosion occurred shortly prior to eruption, due to interaction of the magma with groundwater. The triggered variation in oxygen fugacity results in an oxi-hydroxylised modification of the original structure of the oli-vine, which, after eruption and contemporaneous degassing of volatiles, was overgrown by fresh olivine rims.

Organisation(en)
Department für Lithosphärenforschung
Externe Organisation(en)
Eötvös Loránd University Budapest
Journal
Austrian Journal of Earth Sciences
Band
103
Seiten
101-110
Anzahl der Seiten
10
ISSN
0251-7493
Publikationsdatum
2010
Peer-reviewed
Ja
ÖFOS 2012
105120 Petrologie
Schlagwörter
ASJC Scopus Sachgebiete
Geology, Stratigraphy, Palaeontology
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/61f1d30f-fce5-428f-9cce-2e6fbabdfa2c