Upgrade of microRaman spectrometer for in-situ, high-temperature and high-pressure experiments

Carnegie Institution Of Washington, Washington DC

Investigators

Abstract

Award funds will be used to upgrade the excitation laser used for microRaman spectroscopy, which plays a central role in experimental characterization of minerals, melts, and fluids at high temperature and pressure. These data are central to our understanding of the formation and evolution of the solid Earth, its oceans, and atmosphere. The most important research areas are: 1. Structure of silicate-C-O-H-N components in and partitioning between melt and fluid to advance modeling of transport properties and processes that involve fluids and melts in the Earth and terrestrial planets. 2. Equation-of-state and structure of COH fluids at high temperature and pressure. 3. Characterization of stable isotope partitioning between minerals, melts, and fluids at high temperature and pressure. 4. COH fluid structural speciation and isotopologues in hydrothermal environments These objectives are reached by using externally-heated hydrothermal diamond anvil cells (HDAC) and probing the samples with vibrational (Raman and infrared) spectroscopic methods. The HDAC is employed for sample containment wherein in-situ spectroscopic measurements with samples at desired temperature, pressure, and redox conditions are carried out; optical observations can be made at the same time through the diamond windows.