Rocky Mountain (66th Annual) and Cordilleran (110th Annual) Joint Meeting (19–21 May 2014)

Paper No. 7
Presentation Time: 8:00 AM-5:00 PM

THE USE OF PHOTOGRAPHIC INTERPRETATION TO DETERMINE THE COMPOSITIONAL VOLUME AND NATURE OF MIXED MAGMA FROM BASALT AND RHYOLITE COMPLEXES AT YELLOWSTONE NATIONAL PARK


HASTON, Amber1, ADAMS, Drew1 and PRITCHARD, Chad2, (1)Geology Dept, Eastern Washington University, Eastern Washington University, 130 Science Building, Cheney, WA 99004, (2)Eastern Washington University, Science 119, Eastern Washington University, Cheney, WA 99004, akhaston@eagles.ewu.edu

Petrographic thin sections from the mixed magma complex at Grizzly Lake, Yellowstone National Park display complex mixing structures which make analysis extremely complicated. To address the complex nature of the slides, they were digitally scanned and analyzed using ImageJ software to determine relative composition and volume of the end members. These data were then compared to microprobe analysis obtained from a JEOL 8500F field emission electron microprobe, to determine the efficacy of the photographic interpretation. Such analytical processes could be used in larger scale situations, such as outcrop photos, to estimate volumes of visual end members (felsic and mafic constituents) in a mixed magma situation or metamorphic outcrops. Further, if refined, it could be a viable option in the analysis of fractality of the complicated structures displayed in the Grizzly Lake mixed magma complex.