Structural properties of sodium-rich carbonate-silicate melts: An in-situ high-pressure EXAFS study on Y and Sr

16th International Conference on X-ray Absorption Fine Structure

Pohlenz, J.^1 ; Pascarelli, S.^2 ; Mathon, O.^2 ; Belin, S.^3 ; Shiryaev, A.^4 ; Safonov, O.^5 ; Veligzhanin, A.^6 ; Murzin, V.^7 ; Irifune, T.^8 ; Wilke, M.^1

Helmholtz Centre German Research Centre for Geosciences, Potsdam, Germany^1

ESRF European Synchrotron Radiation Facility, Grenoble, France^2

Synchrotron SOLEIL, Gif-sur-Yvette, France^3

IPCE, Moscow, Russia^4

Institute of Experimental Mineralogy RAS, Chernogolovka, Russia^5

Kurchatov Institute, Moscow, Russia^6

DESY, Hamburg, Germany^7

Ehime University, Matsuyama, Japan^8

关键词: Carbonate melts;    Cooling process;    High-pressure and temperatures;    Highly stables;    Local environments;    Silicate melts;    Transmission mode;    X-ray transmission;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012083/pdf
DOI  :  10.1088/1742-6596/712/1/012083

来源: IOP

【 摘 要 】

In-situ EXAFS combined with a Paris-Edinburgh press (PEP) is an outstanding tool to investigate the local environment of trace elements in melts at high pressure and temperature. A novel design of the pressure assembly ensures a highly stable experimental setup (reaching temperatures of up to 2000 K at 2.5 GPa) while permitting the necessary level of X- ray transmission. This study focuses on the structural incorporation of the geochemically important trace elements Y and Sr in sodium-rich silicate-carbonate melts. Y and Sr K edge EXAFS were collected in transmission mode of the melt (at ∼2.5 GPa, 1600 K) and its respective quench products. Distinct changes in the XANES region suggest a change in site symmetry during the cooling process.