JOURNAL OF PETROLOGY
Journal of Petrology, 2017, Vol. 58, No. 6, 1107–1144 doi: 10.1093/petrology/egx048 Advance Access Publication Date: 21 July 2017 Original Article
Multiple Metasomatism beneath the No´gra´d–Go¨mo¨r Volcanic Field (Northern Pannonian Basin) Revealed by Upper Mantle Peridotite Xenoliths No´ra Liptai1,2, Levente Patko´1, Istva´n J. Kova´cs3*, Ka´roly Hidas4, Zsanett Pinte´r1†, Teresa Jeffries5‡, Zolta´n Zajacz6§, Suzanne Y. O’Reilly2, William L. Griffin2, Norman J. Pearson2 and Csaba Szabo´1¶ 1
Lithosphere Fluid Research Lab, Institute of Geography and Earth Sciences, Eo¨tvo¨s University, Budapest, H-1117, Hungary; 2Australian Research Council Centre of Excellence for Core to Crust Fluid Systems (CCFS) and GEMOC, Department of Earth and Planetary Sciences, Macquarie University, North Ryde, NSW 2109, Australia; 3Hungarian Geological and Geophysical Institute, Budapest, H-1143, Hungary; 4Instituto Andaluz de Ciencias de la Tierra, CSIC & UGR, Avenida de las Palmeras 4, E-18100 Armilla (Granada), Spain; 5Department of Earth Science, The Natural History Museum, London SW7 5BD, UK; 6Department of Earth Sciences, Institute of Isotope Geochemistry and Mineral Resources, ETH Zu¨rich, 8092 Zu¨rich, Switzerland ¶
Corresponding author. E-mail:
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*Present address: Geodetic and Geophysical Institute, MTA Research Centre for Astronomy and Earth Sciences, Sopron, H-9400, Hungary. † Present address: Australian Research Council Centre of Excellence for Core to Crust Fluid Systems (CCFS) and GEMOC, Department of Earth and Planetary Sciences, Macquarie University, North Ryde, NSW 2109, Australia. ‡ Deceased. § Present address: Department of Earth Sciences, University of Toronto, Toronto, ON, M5S 3B1, Canada. Received December 11, 2014; Accepted July 19, 2017
ABSTRACT Peridotite xenoliths from the No´gra´d–Go¨mo¨r Volcanic Field (NGVF) record the geochemical evolution of the subcontinental lithospheric mantle beneath the northern margin of the Pannonian Basin. This study is focused on spinel lherzolites and presents petrography, and major and trace element geochemistry for 51 xenoliths selected from all xenolith-bearing localities of the NGVF. The xenoliths consist of olivine, orthopyroxene, clinopyroxene and spinel 6 amphibole. No correlations between modal composition and textures were recognized; however, major and trace element geochemistry reveals several processes, which allow the distinction of xenolith groups with different geochemical evolution. The xenoliths have undergone varying degrees (7–25%) of partial melting with overprinting by different metasomatic processes. Based on their Mg#, the xenoliths can be subdivided into two major groups. Group I has olivine Mg# between 89 and 91, whereas Group II has Mg#
