Acquisition of an Advanced Optical Microscopy Laboratory for Computer Integrated Analysis of Fault Rock Fabrics and Fractures

Montana State University, Bozeman MT

Investigators

Abstract

0824980 Shaw This proposal seeks funding to acquire a microscopy and sample preparation equipment in order to create a Rock Microstructure of Natural Materials Laboratory at Montana State University. The overall goal of the facility is to image and analyze crystallographic preferred orientation (CPO) fabrics and microstructures. The facility will comprise capabilities for optical orientation analysis with Computer Integrated Polarization (CIP) microscopy and fracture microstructural analysis using epifluorescence microscopy. Requested are an Olympus BX51 scope with fluorescence and digital imaging capabilities fitted with CIP and an Olympus SZX-16 scope with polarization accessories. For digital imaging, a workstation with digitizing monitor is requested. For sample preparation, a precision saw, grinder/polisher and accessories are requested. The instrumentation will be employed for on-going NSF EAR-funded research on seismic rupture pre- and post-rupture plastic deformation in the lower and middle continental crust. Quartz crystallographic orientation will be assayed along with fracture density and grain size distributions to better understand deformation mechanisms and paleostress conditions from middle and deep crust seismic faults. Quartz vein and pseudotachylyte-bearing samples will be analyzed to understand deformation mechanisms. CIP and electron backscatter diffraction (EBSD) will be used to map orientation and this in turn will be related to estimate the strain field during deformation. Associated projects will have the instrumentation applied to analyzing snowpack rheology by determining preferred orientation at sintered grain snow boundaries, apatite orientation in fossil bones as a proxy for stress adaptation and lifestyle, and the orientation of calcite crystals in fossil dinosaur and bird eggs to better understand the evolution of avian reproduction. The instrumentation will be incorporated into existing laboratory space in one of two buildings. The preparation equipment will be incorporated into an existing rock preparation room. Maintenance costs are assumed to be minimal with supply estimates at only ~$1,250 per year. Expendable supplies will be charged to applicable research grants. A nominal fee will be charged to users in anticipation of computer and software maintenance costs. The MNM lab will compliment instrumentation already available at MSU. The requested EBSD sample preparation equipment will allow higher sample throughput and alleviate the need to prepare samples in another department. Interdisciplinary and inter-departmental collaboration will be possible through the new facility. Due to the robust nature of the requested equipment, students will gain hands-on experience and education. Due to the unique nature of this facility, disseminated results will be of broad interest. ***