Journal article

Geochemical evolution of Monowai volcanic center: New insights into the northern Kermadec arc subduction system, SW Pacific

C Timm, IJ Graham, CEJ De Ronde, MI Leybourne, J Woodhead

Geochemistry Geophysics Geosystems | AMER GEOPHYSICAL UNION | Published : 2012

Abstract

We present trace element and Sr-Nd-Pb isotope data on volcanic rocks recovered from the submarine Monowai volcanic center, which marks the midpoint of the ∼2500 km long Tonga-Kermadec arc. The center consists of a large (12 × 9 km) partly hydrothermally active caldera and a 12 km diameter ∼1500 m high volcanically and hydrothermally active stratovolcano. The stratovolcano lavas are tholeiitic basalts, which show variable evidence for plagioclase (±pyroxene) accumulation. The caldera lavas range from basalt to andesite, with the compositional variation being consistent with fractional crystallization as the dominant process. The mafic Monowai magmas were generated by relatively high degrees (..

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University of Melbourne Researchers

Grants

Awarded by FRST (Foundation of Research and Technology, New Zealand)


Funding Acknowledgements

We wish to acknowledge the contribution of major and trace element data from Ian Smith, University of Auckland, New Zealand. Roland Maas is thanked for laboratory assistance at Melbourne University, Australia. Discussions with C. J. N. Wilson, R. Sutherland, and R. Wysoczanski helped to develop ideas in this paper. We also would like to thank John Gamble and an anonymous reviewer for constructive and helpful reviews, which improved the paper. Joel Baker is thanked for editorial handling. This work is a part of the MWE program funded by FRST (Foundation of Research and Technology, New Zealand) contract C05X0406.