Date of Award
Fall 10-10-2025
Level of Access Assigned by Author
Open-Access Thesis
Degree Name
Doctor of Philosophy (PhD)
Department
Earth Sciences
First Committee Advisor
Andrei V. Kurbatov
Second Committee Member
Paul A. Mayewski
Third Committee Member
Kirk Maasch
Additional Committee Members
Daniel Dixon
Levan G. Tielidze
Abstract
This dissertation focuses on improving the detection and reconstruction of paleoenvironmental signals in ice cores using advanced analytical techniques. The research integrates stratigraphic analysis and glaciochemistry to evaluate ice archives across timescales ranging from seasonal to millennial.
The first chapter presents a glaciochemical study of the Kazbegi Glacier, located in the Central Caucasus. The analysis documents the effects of recent regional warming on the physico-chemical properties of the snowpack and the preservation of paleoclimate signals. We found that the glacier surface is increasingly affected by summer melt. However, preserved stratigraphy in the deeper glacial layers indicates that the glacier retains a valuable paleoclimate archive. This unique site potentially captures aspects of human history spanning several thousand years.
The second chapter focuses on the Allan Hills Blue Ice Area, Antarctica, and investigates a stratigraphic discontinuity around the Marine Isotope Stage 11 (~400–375 ka). The observed discontinuity points to significant elevation loss in East Antarctica, possibly accompanied by a retreat of the West Antarctic Ice Sheet. These findings are supported by globally distributed paleoclimate data and reinforce the proposed vulnerability of ice sheets during prolonged interglacial periods. This research contributes to a better understanding of the potential future evolution of the Antarctic Ice Sheet.
The third chapter develops and applies an improved methodology for laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to quantify Pb, Fe, Cu, Mg trace elements in ice core samples. We also developed a new approach to address the issue of increased non-homogeneity in frozen ice standards at higher elemental concentrations. This was achieved by using a combination of standards made from frozen solutions and filters soaked in the same solutions. The new method was tested on low-concentration, Eemian-aged ice core samples from the Allan Hills Blue Ice Area, Antarctica.
Together, the three chapters of this dissertation contribute to methodological advancements and provide new scientific insights into ice core paleoclimate research.
Recommended Citation
Gadrani, Lela, "Paleoenvironmental Reconstruction from Ice Cores Using Advanced Analytical Techniques" (2025). Electronic Theses and Dissertations. 4267.
https://digitalcommons.library.umaine.edu/etd/4267