Date of Award
Spring 5-10-2014
Degree Type
Thesis
Degree Name
Master of Science (MS)
Department
Geosciences
First Advisor
Dr. Daniel M. Deocampo
Second Advisor
Dr. W. Crawford Elliott
Third Advisor
Dr. Nadine Kabengi
Abstract
The proportion of authigenic to detrital clay minerals in terrestrial sediments is variable. It has previously been hypothesized that pure Mg-silicates in regions such as Amboseli Basin in Kenya occur due to the absence of Al-rich detritus. We tested this by replicating two Mg-silicate synthesis experiments while adding Al-rich smectite. The first study produced an X-ray amorphous Mg-silicate gel, with little response to addition of Al-rich smectite. The second experiment shifted the 060 peak associated with clay octahedral sheets, suggesting we synthesized trioctahedral domains in a smectite structure. Peak height increased linearly with more heating, indicating crystallinity changes. These results confirm that Al-rich detritus can influence the mineralogy of authigenic clays in saline, alkaline settings. By examining how clay neoformation is affected by silica saturation, we can better understand how the clays found in Neogene lacustrine environments are formed and the climate and of that time.
DOI
https://doi.org/10.57709/5518970
Recommended Citation
Pickering, Rebecca, "Tri-Octahedral Domains and Crystallinity in Synthetic Clays: Implications for Lacustrine Paleoenvironmental Reconstruction." Thesis, Georgia State University, 2014.
doi: https://doi.org/10.57709/5518970