Tracing fluid pathways in rocks and minerals
August 12, 2015 Leave a comment
– NanoSIMS engineer no. 1: This is Wednesday, but already feels like a Friday. Why does it feel like a Friday?
– NanoSIMS engeneer no. 2: That’s because she made us work so hard this week…
– Me: Sorry guys, I have to keep my supervisor happy.
Of course, that was a half-joke. But we worked quite intensively during the last 1.5 weeks at the NanoSIMS facility in Perth. You do not want to waste time when a use of machine costs several thousand dollars a day.
NanoSIMS is a high resolution ion-microprobe (NanoSIMS), which allows a detailed nano-scale mapping of various elements and isotopes. It can be used for rocks, metals and even biological samples. The samples I mapped come from experiments, where feldspar-rich rocks were reacted with an 18O-enriched fluid. Naturally most of the oxygen in minerals occur in a 16O form, so when we add 18O to the fluid, we are able to track the exact extent of the fluid-rock interaction, even if it is not reflected by chemical changes in the rock. Very exciting results and we were really pushing the capabilities of what this machine can do.