Journal article
Lithospheric control on geochemical composition of the Louisville seamount chain
Mineralogical magazine, Vol.75(3), p508
Goldschmidt 2011 (2011)
Jun 2011
Abstract
Chemical changes with time in lavas erupted on long-lived seamount chains can be used to test models for the origin of intraplate magmatism and examine the effect of sub-seamount lithosphere on volcanism. Major and trace element and Sr, Nd, and Pb isotope data for lavas from 12 seamounts along the westernmost 1500 km of the Louisville Seamount Chain (LSC) in the SW Pacific show that magmatism was compositionally remarkably uniform between 80 and 40 Ma. All 56 samples analysed are alkalic or transitional; most are basalts. The youngest lavas from a given seamount tend to have the least enriched incompatible element compositions. Unlike Hawaiian volcanoes, Louisville volcanoes appear not to pass through a tholeiitic shield-building stage. The oldest Louisville seamounts formed close to the Osbourn Trough fossil spreading centre, but there is no obvious effect on the composition of LSC lavas. Nor do Osbourn Trough MORB contain any contribution from Louisville mantle, which suggests that spreading at the Osbourn Trough ceased well before the construction of Osbourn Guyot at 79 Ma. Lavas from volcanoes in the central part of the LSC are more variable and extend to more enriched compositions. These volcanoes tend to be smaller and more widely spaced, and were underlain by the oldest, thickest oceanic lithosphere. Smaller degrees of melting of heterogeneous mantle may explain the more variable compositions of these volcanoes.
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Details
- Title
- Lithospheric control on geochemical composition of the Louisville seamount chain
- Creators
- Christoph Beier - Universitaet Erlangen-Nuernberg, GeoZentrum Nordbayern Erlangen DEU GermanyMarcel RegelousJohn MahoneyLoyc VanderkluysenKarsten HaaseAnonymous
- Publication Details
- Mineralogical magazine, Vol.75(3), p508
- Conference
- Goldschmidt 2011 (2011)
- Publisher
- Mineralogical Society
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Biodiversity, Earth, and Environmental Science (BEES)
- Identifiers
- 991021015346304721