Colloquium: Tom Zega

Tom Zega, Lunar & Planetary Laboratory, The University of Arizona

Abstract - Spatially resolved analysis of meteorites and other planetary materials is fundamental to cosmochemical research. Over the past decade, advances in ion and electron optics have led to the development of a new generation of instruments capable of providing chemical and structural information on planetary materials at increasingly smaller spatial scales. Secondary ion mass spectrometry (SIMS) with a NanoSIMS can provide isotopic information on samples down to 50 nm. Aberration-corrected and monochromated electron optics in the transmission electron microscope (TEM) coupled with electron energy-loss and large solid-angle energy-dispersive X-ray spectroscopy (EELS, EDS, respectively) have enabled direct imaging of atomic structure and atomic-column spectroscopy. By themselves, the data provided by these instruments have enabled new insights into the origins of planetary materials, but coordination of these data sets, via the focused-ion-beam scanning-electron-microscope (FIB-SEM), has become an extremely powerful tool for cosmochemical research. Coordinated analysis will be essential for returned sample investigation. My talk will provide a broad overview of the way our research group applies the such tools to address problems and questions in cosmochemistry.