Molybdenum and uranium are redox sensitive elements that experience isotope fractionation in the Earth-surface environment. Recent studies have explored transfer of these fractionated signals subduction zones to arc magmas, but less is known about full variation isotopic tracers mantle, particularly domains mantle may feed hot spots. Here, we present Mo U data for lava samples from Pitcairn, Sa...

This dissertation discusses the experimental results designed to constrain the processes of MORB generation. The main focus of this study is to investigate the location and the related processes of the transformation boundary from spinel to garnet peridotite facies at subsolidus conditions, because the presence of garnet in melting residues has significant influence to the conclusion drawn from...

Chemical differences between mid-ocean ridge basalts (MORBs) and ocean island basalts (OIBs) provide critical evidence that the Earth's mantle is compositionally heterogeneous. MORBs generally exhibit a relatively low and narrow range of (3)He/(4)He ratios on a global scale, whereas OIBs display larger variability in both time and space. The primordial origin of (3)He in OIBs has motivated hypo...

The oxidation state of iron in mantle-derived melts is commonly used to determine the oxygen fugacity (fO2) magmas and their related sources. accurate precise determination ratio Mid-Oceanic Ridge Basalt (MORB) glasses has been a matter controversy for last three decades. None wet chemical methods literature measure this converge toward consensus value. same difficulties have observed most rece...