It’s not as fun as it sounds—but, boy, it’s important. The samples we took from the fossil prairie have been going through several prep phases to run them for chemical isotopes. We are currently in the sonication step.
What is sonication? It’s a pretty decent question, considering I had no idea as of three weeks ago. Basically, it’s a machine roughly the size of a toaster oven, but with less toast. It has to be filled with deionized water as so not to mess with the chemical composition of any samples. We then place a mesh-wire tray in the sonicator, and fill a beaker with more deionized water. Our selected rock sample goes into the beaker, which we sit on the mesh tray. After we place a cover over the tray, we’re just one button push away from successfully sonicating our rock. What a rush, eh?
Once the sonicator is running, it sends sonic waves through the water, which shake off tiny clay particles from our sample. This is a much finer method of cleaning our samples, as the tiny waves can reach into places a brush can’t. For each sample, we run a standard of three times through the sonicator, at eight minutes each. After one run, we replace the dirty beaker water with a fresh drink of deionized water. We know that the sample is completely clean when the water comes out clear. Most samples have taken us five to six runs to be truly clean.
Although successfully cleaning our rock samples is a slow process, it’s a very important step to our overall data collection. If we were to run these rock samples without having properly cleaned them, we could very well be collected data from the stuck-on clay, and not the actual rock. They clay is very likely to be from a completely different time, and would have very different readings, if we could get anything from it, period.
After we have a good number of clean samples from each section of rock, we will hopefully be able to begin drilling. What could be more fun than sonication? Obliterating your sample into an easily-testable, fine-grained powder!
--Bobbi Minard
--Bobbi Minard