A scanning electron microscope (SEM) is great for high magnification images that also contain information about the chemical composition of the different minerals in meteorites. SEM is also a quick way to do a qualitative analysis of a sample, say for example, detecting nickel in iron meteorites with energy dispersive spectroscopy (EDS).
My instrument of choice for definitive ID of stony meteorites is the electron microprobe. This also has SEM imaging capability. In less the hour, on a calibrated electron microprobe, I can make a definitive ID, although unequilbrated chondrites can take more time to narrow down the possibilities. Some of the key geochemical quantities that help in categorizing are, Fe/Mn of olivines and pyroxenes, the fayalite and ferrosilite content of the olivines and pyroxenes, the anorthite-albite content of plagioclse, and a few other parameters, plus the percent mineralogy and other textural characteristics. So for a simple example lunar olivines usually have higher Fe/Mn than terrestrial basalt olivines. Check out this page's second figure for an overview of Fe/Mn versus plagioclase content of planetary basalts: http://www.imca.cc/mars/martian-meteorites.htm Carl Agee -- Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: a...@unm.edu http://epswww.unm.edu/iom/pers/agee.html --------------------------------l---------------------------------------------- Geophysics, meteorites, and Electron microscopy Barb and Jake Baker bakers5acres at frontiernet.net Tue Sep 6 10:50:46 EDT 2011 Previous message: [meteorite-list] [AD] Canyon Diablo 2,7 kg. CHEAP! Messages sorted by: [ date ] [ thread ] [ subject ] [ author ] ________________________________ Could someone tell me, in Microscopy 101 language: How is an electron microscope used in the study of meteorites? Using electron microscopy - what differences are apparent between meteorites and terrestrial rocks? For instance what are the microscopy differences between lunar basalt and terrestrial basalt? Thanks ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
