site rencontre gratuit sarreguemines Sorry that it has been so long since our last post. We have all been very busy back here at UCSB, our home institution. The field work in Antarctica that you followed along with is only one aspect of this project. Now it’s time for the “science-y” stuff. We have been organizing our samples and preparing them for dating and geochemistry.
http://www.homesap.fr/43091-dtf40181-demain-nous-appartient-telecharger.html Here’s Jason Schmidt, a research assistant working with us this summer, helping archive our samples in the dingy basement of our Earth Science department. We start with whole-rocks collected in the field and try to extract accessory minerals that are useful for dating and geochemistry. We crush the rocks using the disk mill you see below and then send the material down the water table (basically a glorified gold pan). This sorts the material based on grain size and grain density.
Next we use special chemicals to further separate the material based on density. Here I (Graham) am working in the fume hood, isolating dense minerals such as zircon, monazite, titanite, and garnet.
We take the most dense fraction from the “heavy liquids” step, and separate different minerals based on their magnetic properties. We use this funny looking contraption, the Frantz isodynamic separator. After this step, we hopefully have nearly pure separates containing only the accessory minerals that we are interested in.
It’s time to image our samples before analyzing them on the mass-spectrometers. We take cathodoluminescence images using a scanning election microscope.
Finally! It’s time to get some data! The real interesting stuff happens in our plasma-source mass spectrometer lab. We have two lasers and two inductively coupled plasma- mass spectrometers that enable us to measure a wide range of isotopes as well as the concentration of trace elements at several ppm precision!
More to come on the lab work this summer… Stay tuned for updates on the upcoming field season as well!