The oxidation state of mantle-derived arc magmas

We will determine oxidation states of island arc magmas in their earliest states of generation in Earth's mantle. Oxidation state controls speciation of gases dissolved in the magmas and nature of economically-important, magmatic-related ore deposits. Recent evidence suggests equivalent redox conditions at source for mid-ocean ridge and arc magmas and progressive oxidation of the latter during ascent. We will test this hypothesis with unique suites of recently obtained primitive arc magmas and mantle samples using newly developed analytical techniques. Resolution of equivalence in oxidation state of ridge and arc magmas, or oxidation at arc source will be the outcome.