Friday 19 November 2010

Final experiment of the project

What is probably my final experiment (for this project) is running. We started it yesterday morning. My current contract runs through December. At 2 to 3 weeks per experiment, this one is probably it. This fact left me torn as to what conditions to choose for the run.

I've got a couple of previous experiments which turned out to be very difficult to analyze due to improper sealing of the capsules. Therefore I'd love to re-run them, with properly sealed capsules, in hopes of better grain sizes, so that I can get good analyses of the phases present.

We've got some data from experiments run by a predecessor of mine which use a slightly different bulk composition. In theory the difference between the two bulk compositions shouldn't really matter—most of the difference is in the amount of SiO2, which is still in excess in the bulk composition I use (as we can tell from the presence of quartz). However, when I calculated what phases should be present for each bulk composition using Perple_X, it said that at the P/T of those old runs the new bulk should have different phases. Therefore I'd like to re-run one of those to see if there is, in fact, any difference in the results with the slightly different composition.

And, finally, both my boss and I wanted to do another run in a P/T space that is expected to have both garnet and talc, since this project is about defining the stability field for talc. That makes three different experiments I want to run, and sufficient time available to do one of them. Decisions, decisions!

We eventually decided to go with a totally new run—while the data from the "bad" runs isn't complete, we do know that there isn't talc present at those conditions, which is the single most important question. Therefore there is more value in obtaining new data than clarifying old data in this case.

All in all, this project has convinced me that 1.5 years is simply not enough time for such a project. However, I am pretty certain that if it had been a 3 year contract that was now approaching its end I'd still be sitting here thinking about the other experiments I would have liked to have run, had there been time/budget to do so. Ah, the life of a research scientist—so many questions to be asked, so many things to do to try to answer them, but no matter which ones we choose, it never, really, feels like we've got time enough to obtain all of the data we would like to have…

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