Graduate Studies
Date of this Version
4-2013
Citation
Brenizer, L.E., 2013, Petrography and Geochemistry of Carbonate Sediments on the Ross Sea Continental Shelf, Antarctica, M.Sc. thesis: Department of Earth and Atmospheric Sciences, University of Nebraska–Lincoln.
Abstract
This investigation integrates petrography, geochemistry, and radiocarbon dating to examine diagenetic processes and their effect on preservation of carbonate sediments in cold-water settings. Petrographic observation of coarse grains in thin section revealed evidence for widespread bioerosion. Microbores in skeletal carbonate grains remain empty, increasing surface area, leaving them susceptible to further breakdown. Examination of the fine fraction indicated much of the fine carbonate consists of bioeroded bryozoan fragments. Observations indicate bioerosion leads to fragmentation. Bottom currents extend exposure time on the seafloor and winnow the fine fraction. The noncalcareous fine fraction is composed of reworked Miocene-Recent marine diatoms, foraminifera, sponge spicules, and siliciclastic debris. Radiocarbon analyses of skeletal grains yielded ages: >22.7±0.9ka (n=9) and
Advisor: Tracy Frank
Comments
A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Earth and Atmospheric Sciences, Under the Supervision of Professor Tracy D. Frank. Lincoln, Nebraska: April 2013
Copyright (c) 2013 Lindsey Erin Brenizer