Meteorite Classification: Learning the Tools of the Trade

Poster Image
Event poster; details follow in description
Poster Session
A
Poster Number
01
Project Author(s)
Hayden Babst, Lichen McHenry
Institution
Portland State University
Project Description

Classification of meteorites provides an opportunity for undergraduate students to engage in space-related STEM research activities, by becoming skilled in the use of an optical microscope and familiar with the manipulation and evaluation of mineral-chemical data. Work performed is scientifically useful and necessary. Two undergraduates (Babst, McHenry) and one post-bac (Bintliff) examined meteorites in thin section using an optical microscope in plane-polarized, cross-polarized, and reflected light. They used Photoshop to process images of their sections taken in all three light modes via a digital camera attached to the microscope. These data were used to determine the shock stages and weathering grades for each sample. Supervisors obtained mineralchemical data using a Zeiss Sigma VP FEG scanning electron microscope (SEM). Data was transferred to an Excel spreadsheet for evaluation and calculation of end member compositions. Meteorite chemical class and petrographic type were determined from these data. All three meteorites are ordinary chondrites, with the classifications of: CML0627asH5 W3 (two lithologies with different shock stages), CML 0629asL6 S4 W2, and CML1314 as L6 S4 W3. Formal write-ups for the three newly characterized meteorites have been submitted to the nomenclature committee of the Meteoritical Society for official approval and naming.