The second full day of the American Geophysical Union conference is always an interesting one, as the exhibit hall opens. Vendors, funding agencies, publishers, universities, and other organizations are present at booths, filling a huge hall. It’s a great place to go to see the latest and greatest technology, such as the 4 meter long flume table from Emriver. I took a picture, but forgot to bring my card reader so I have no way to transfer it off of my camera. It shall have to suffice for now to say that it was stunning.
In addition to some very interesting discussions with people at posters, I went to the Volcanology, Geochemistry, and Petrology award lectures. The second lecture, by Craig Manning, was a fairly clear discussion about the inadequacies of previous thinking about thermodynamics in hot (900–1100 °C), high-pressure (5–10 kbar [I think I have that pressure right]) hydrothermal systems (e.g. subduction zones) and some new experimental results and conceptual models which seem to fit better.
My mind was blown fairly early in the talk when he pointed out that under those temperature and pressure conditions, neutral pH for water is around 4. I also haven’t thought enough about ionic liquids (e.g. molten sodium chloride), or the ternary phase diagram of H2O, CO2, and NaCl, particularly not under high temperature/pressure. However, in the thermodynamic sense these systems do have some predictable behaviors when thought of this way, and the data seem to fit those predictions. The fluids have a tendency to become quickly rich in silica (SiO2), which gives rise to the quartz veins commonly found in metamorphic rocks. In these models it is not hard to then transition from silica-in-salt-solution toward partial melting of a type found in metamorphic and volcanic rocks.
The afternoon held interesting talks on isotope systems of relevance to volcanic measurements (estimating sulfur emissions and speciation), as well as good discussions with people I met in the hallways or poster sessions. Later in the afternoon I came across a former labmate, and it was good to catch up with her for a while and discuss the various challenges of being an early-career scientist. Dinner, debrief, and further discussion of early-career issues with my conference buddy capped off my day.
Tomorrow has yet more interesting talks and posters, and there are a few people on my to-talk-with list who I will need to track down.