Refractory Magmas in Back-Arc Basin Settings-Experimental Constraints on the Petrogenesis of a Lau Basin Example

Submarine back-arc lava with arc signature: Fonualei Spreading Center, northeast Lau Basin, Tonga

[1] We present major, volatile, and trace elements for quenched glasses from the Fonualei Spreading Center, a nascent spreading system situated very close to the Tofua Volcanic Arc (20 km at the closest), in the northeast Lau Basin. The glasses are basalts and basaltic andesites and are inferred to have originated from a relatively hot and depleted mantle wedge. The Fonualei Spreading Center sh...

Long-Term Stability of Back-Arc Basin Hydrothermal Vents

Since the discovery of hydrothermal vents 40-years ago, long-term time-series have focused on mid-ocean ridge systems. Based on these studies, hydrothermal vents are widely considered to be dynamic, ephemeral habitats. Under this premise, national, and international regulatory bodies are currently planning for the commercial mining of polymetallic sulfide deposits from hydrothermal vents. Howev...

Chlorine in submarine glasses from the Lau Basin: seawater contamination and constraints on the composition of slab-derived £uids

Measurements of chlorine concentrations in matrix glasses from 18 primitive (s 6 wt% MgO) and eight evolved lavas from active spreading centers in the Lau Basin back-arc system provide insight into the processes which control chlorine concentrations in subduction-related magmas, and can be used to investigate chlorine enrichment related to fluids derived from the underlying subducted slab. Chlo...

The West Philippine Basin: An Eocene to early Oligocene back arc basin opened between two opposed subduction zones

Oxygen Isotope Compositions of Mineral Separates from Snc Meteorites: Constraints on the Petrogenesis of Martian Magmas

Introduction: Martian (SNC) meteorites are igneous rocks that range from a reduced, trace-element depleted end member to an oxidized, trace-element enriched end member [1-3] (Figure 1). One interpretation of this trend is that relatively reduced, depleted magmas are partial melts of a reduced peridotitic mantle, whereas more oxidized, enriched magmas are mantle-derived magmas contaminated by ox...