The Redox state of pre-shield stage magmas at Hawaii

The experiment involves S K-edge XANES spectroscopy of natural (1-2 mm), inhomogeneous (on a 100s of micron scale), basaltic glasses dredged from a water depth of 3,879 m off Hawaii. This requires tuneable X-rays at ~ 2.5 keV and a microbeam. The feasibility of the experiment at the Australian Synchrotron was discussed recently with Chris Glover (XAS) and previously with David Paterson (XFM). S K-edge spectroscopy is not possible at XFM or XAS due to the lower limit of the monochromators (~ 4 keV). The development of a spectroscopic capability in this energy range is a stated priority of the AS in the "Bright" document.