Metamorphic petrology

 
EPMA, metamorphic petrology
Mapping magnetite overgrowths in dunite with Electron Probe Microanalyzer

Fe and Mg WDS X-ray maps acquired at 15 kV and 100 nA ( 0.7 µm step size, 10 ms dwell time) revealing magnetite overgrowths onto chromite grains in a partially-serpentinized dunite sample from Southern Vermont, USA. Electron Probe Microanalysis is used to investigate the petrogenesis of this ultramafic body that was part of the Earth’s upper mantle prior to the obduction event during the Taconic Orogeny.

Sample collected by John Mark Brigham and analyzed on CAMECA SXFive at Syracuse University, USA by W. Nachlas. Image courtesy of W. Nachlas.

Winning image for the month of November 2020