HEAVY MINERAL ANALYSIS OF OFFSHORE SEDIMENT CORES, EAST ANTARCTICA

The Ocean Drilling Program (ODP) has made efforts to drill a transect of cores in the Prydz Bay area of East Antarctica, located south of the Indian Ocean. It is there that sediment has been deposited, after erosion by the Lambert Glacier, of high grade metamorphic rocks, mafic dikes, felsic igneous intrusions, and siliciclastic sedimentary rocks with coal measures. The core samples were taken from ODP sites 1166 and 1167 for heavy mineral analysis of the sand fraction. The purpose of this study is to characterize the provenance of the sediments and to reconstruct regional changes in ice-flow through time. The portions of the cores that were chosen for analysis had the greatest amount of sand. Samples were sieved to a fraction between 63 and 250 micrometers to acquire the sand fraction and then were further divided through a heavy liquid separation technique to obtain the heavy minerals. The heavy mineral fraction was then put onto microscope slides for mineral analysis. Results included an abundant amount of garnet and hypersthene as well as small amounts of rutile, augite, sillimanite and amphiboles. Preliminary SEM imaging results show well formed garnet and hypersthenes crystals. Continuing work includes an SEM-EDX chemical analysis and complete count/identification of grain mounts.