Glaciology Commons^™

Glacial Isostatic Adjustments And Their Impact On Sea-Level Predictions, Dayne M. Williams, Jeanne Sumrall

SACAD: Scholarly Activities

Relative sea level adjustments and their effects directly contribute to modern day climate change and ocean knowledge. This is shown through Glacial isostatic adjustment models which depend on ice thickness, time period, and core analyzations within a local region. These models demonstrate a direct correlation between RSL, era of retreat, and ice thickness even with comparison of other similar models, with some minor discrepancies. These discoveries led to several new advancements within the field of glaciology regionally and nationally. Generally concluding that the research done isn’t sufficient and more data regionally is needed to study its impacts more detailed.

The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford

Theses/Capstones/Creative Projects

This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …

Geomorphic And Paleoclimatic Implications Of Glacial Extent Records In The Sierra Nevada Del Cocuy, Colombia During Termination 1, Jordan Nickerson Herbert

Dartmouth College Master’s Theses

Reconstructions of past glacial extents using geomorphic mapping and cosmogenic dating provide an opportunity to infer past climates. A record of the past extents of tropical mountain glaciers is particularly useful because there are few other means to reconstruct past temperatures in high-altitude, low-latitude locations. The tropics play an outsized role in mediating global climate, yet there is a lack of understanding of how the tropics may have influenced past climate changes such as the most recent deglaciation (Termination 1, ~18–11.7 ka). Improving reconstructions of tropical mountain glaciers will aid in understanding the role of the tropics in the global …

Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison

Mahurin Honors College Capstone Experience/Thesis Projects

Geochemical fluxes in aqueous studies are an essential component of research to understand weathering and changes in a hydrologic system. These data can indicate any discrepancies, outliers, or gradual changes in a water environment to gain information on pollutants, carbon cycles, biological input, etc. Glacial melt is the majority of the surface water present throughout the country. The melting amount is increasing with the temperatures, which can be monitored by the changes in geochemical flux during increased discharge in glacial rivers. A high-resolution data set of Sόlheimajökull Glacier in Iceland was used to determine how changing climatic conditions for the …

Be-10/Be-9 Ratios Reflect Antarctic Ice Sheet Freshwater Discharge During Pliocene Warming, Rachel D. Valletta, Jane K. Willenbring, Sandra Passchier, Chiara Elmi

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Along glaciated margins, ratios of meteoric cosmogenic beryllium‐10, ¹⁰Be, normalized to its stable isotope, ⁹Be, reflect an environmental signal, driven ultimately by climatic change. We explore the application of this isotopic pair as a proxy for East Antarctic Ice Sheet dynamics. We analyze ¹⁰Be/⁹Be in middle Pliocene glaciomarine sediments offshore the Wilkes Land Region (Integrated Ocean Drilling Program (IODP) Site U1361A) and examine our new record alongside existing biochemical/geochemical records (Ba/Al, opal %_wt, εNd, and ⁸⁷Sr/⁸⁶Sr). ¹⁰Be/⁹Be ratios reach local maxima during pulsed, mild warming events and …

Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga

Masters Theses & Specialist Projects

An investigation into the carbon dynamics and weathering processes occurring in Icelandic glacial-fed streams was conducted during the spring to summer seasonal transition in June of 2017. Four major outlet rives were sampled from the glaciers of Gígjökull, Steinsholtsjökull, Sólheimajökull, and Falljökull. Markarfljót, the major river that Gígjökull, Steinsholtsjökull, and many other glaciers drain into, was also sampled. Longitudinal sampling occurred at all sites to capture downstream trends in the hydrogeochemistry and carbon dynamics. Distinct differences in geochemistry between glacier surface meltwater, sub-glacial waters, pro-glacial lake water, and post-mixed downstream samples were evident in the data. Glacier surface streams were …

Evidence For Ephemeral Middle Eocene To Early Oligocene Greenland Glacial Ice And Pan-Arctic Sea Ice, Aradhna Tripati, Dennis Darby

OES Faculty Publications

Earth's modern climate is defined by the presence of ice at both poles, but that ice is now disappearing. Therefore understanding the origin and causes of polar ice stability is more critical than ever. Here we provide novel geochemical data that constrain past dynamics of glacial ice on Greenland and Arctic sea ice. Based on accurate source determinations of individual ice-rafted Fe-oxide grains, we find evidence for episodic glaciation of distinct source regions on Greenland as far-ranging as ~68°N and ~80°N synchronous with ice-rafting from circum-Arctic sources, beginning in the middle Eocene. Glacial intervals broadly coincide with reduced CO_{2 …}

Surficial Geology Of York College Campus (Queens) And Montauk Point (Long Island): An Open Access To Geoscience Education, Nazrul I. Khandaker, Stanley Schleifer, Krishna Mahabir, Erik Menjivar, Ality Aghedo, Dennis Baidoo, Tenzin Choeying, Vanessa Erwin, Jonathan Xavier, Laboni Molla, Akeed Alrubay

Publications and Research

To evaluate compositional and textural differences among the samples collected from York College (YC) campus (Queens), Montauk Point (MP) and Hither Hills (HH), Long Island, emphasis is given to the general geologic setting, overall grain size distribution, and relative abundances of light and heavy mineral assemblages. Geologic setting encompasses outwash plains (York College), fluvioglacial and glacial (Montauk Point) and beach and dune complex (Hither Hills). YC samples were collected from depth ranging 40 cm to 250 cm and are mostly an assortment of medium to coarse sand, granule to cobble sized, minor silt, and clay. Presence of low angle cross …

Processes Controlling Carbon Cycling In Antarctic Glacier Surface Ecosystems, Elizabeth A. Bagshaw, Martyn Tranter, Jemma L. Wadham, Andrew G. Fountain, A. Dubnick, S. Fitzsimons

Geology Faculty Publications and Presentations

Glacier surface ecosystems, including cryoconite holes and cryolakes, are significant contributors to regional carbon cycles. Incubation experiments to determine the net production (NEP) of organic matter in cryoconite typically have durations of 6-24 hours, and produce a wide range of results, many of which indicate that the system is net heterotrophic. We employ longer term incubations to examine the temporal variation of NEP in cryoconite from the McMurdo Dry Valleys, Antarctica to examine the effect of sediment disturbance on system production, and to understand processes controlling production over the lifetimes of glacier surface ecosystems. The shorter-term incubations have durations of …

Geogram 2014, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

The Monica (Monitoring Of Ice Within Caves) Project: A Multidisciplinary Approach For The Geophysical And Paleoclimatic Characterization Of Permanent Ice Deposits In The Southeastern Alps, Renato R. Colucci, Emanuele Forte, Barbara Stenni, Marco Basso Bondini, Mauro Colle Fontana, Costanza Del Gobbo, Daniele Fontana, Doriana Belligoi, Valter Maggi, Marco Filipazzi

The International Workshop on Ice Caves

On days 30 September and 1-2 October 2013, a 7.8 m long ice core has been extracted from a permanent ice cave deposit in the Southeastern Alps (Vasto’s cave, Mt.Canin - Julian Alps). Each 20 to 100 cm long section of the ice core have been immediately stored in plastic bags and preserved thanks to dry ice. The ice samples, thanks to the helicopter, has been subsequently brought on valley and promptly stored in a refrigerated van, made available by BoFrost. Thus the ice cores has been transported intact to the EUROCOLD laboratory in Milan. These operations have been carried …

Geogram 2013, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Origin And Provenance Of Spherules And Magnetic Grains At The Younger Dryas Boundary, Yingzhe Wu, Mukul Sharma, Malcom A. Lecompte, Mark N. Demitroff, Joshua D. Landis

Dartmouth Scholarship

One or more bolide impacts are hypothesized to have triggered the Younger Dryas cooling at ∼12.9 ka. In support of this hypothesis, varying peak abundances of magnetic grains with iridium and magnetic microspherules have been reported at the Younger Dryas boundary (YDB). We show that bulk sediment and/or magnetic grains/microspherules collected from the YDB sites in Arizona, Michigan, New Mexico, New Jersey, and Ohio have (187)Os/(188)Os ratios ≥1.0, similar to average upper continental crust (= 1.3), indicating a terrestrial origin of osmium (Os) in these samples. In contrast, bulk sediments from YDB sites in Belgium and Pennsylvania exhibit (187)Os/(188)Os ratios <<1.0 and at face value suggest mixing with extraterrestrial Os with (187)Os/(188)Os of ∼0.13. However, the Os concentration in bulk sample and magnetic grains from Belgium is 2.8 pg/g and 15 pg/g, respectively, much lower than that in average upper continental crust (=31 pg/g), indicating no meteoritic contribution. The YDB site in Pennsylvania is remarkable in yielding 2- to 5-mm diameter spherules containing minerals such as suessite (Fe-Ni silicide) that form at temperatures in excess of 2000 °C. Gross texture, mineralogy, and age of the spherules appear consistent with their formation as ejecta from an impact 12.9 ka ago. The (187)Os/(188)Os ratios of the spherules and their leachates are often low, but Os in these objects is likely terrestrially derived. The rare earth element patterns and Sr and Nd isotopes of the spherules indicate that their source lies in 1.5-Ga Quebecia terrain in the Grenville Province of northeastern North America.

Glacial Shortcut Of Arctic Sea-Ice Transport, Michael Stärz, Xun Gong, Rüdiger Stein, Dennis A. Darby, Frank Kauker, Gerrit Lohmann

OES Faculty Publications

Due to the lack of data, the extent, thickness and drift patterns of sea ice and icebergs in the glacial Arctic remains poorly constrained. Earlier studies are contradictory proposing either a cessation of the marine cryosphere or an ice drift system operating like present-day. Here we examine the marine Arctic cryosphere during the Last Glacial Maximum (LGM) using a high-resolution, regional ocean-sea ice model. Whereas modern sea ice in the western Arctic Basin can circulate in the Beaufort Gyre for decades, our model studies present an extreme shortcut of glacial ice drift. In more detail, our results show a clockwise …

Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Reservoir Potential Of Sands Formed In Glaciomarine Environments: An Analog Study Based On Cenozoic Examples From Mcmurdo Sound, Antarctica, Christopher R. Fielding, Brian A. Blackstone, Tracy D. Frank, Zi Gui

Department of Earth and Atmospheric Sciences: Faculty Publications

This paper provides documentation of unexpectedly high-reservoir-quality glaciomarine sands found in the Cenozoic succession beneath McMurdo Sound, Antarctica, as an analogue study for evaluations of hydrocarbon prospectivity in basins elsewhere. The Oligocene to Lower Miocene succession of the Victoria Land Basin, an extant portion of the West Antarctic Rift System, comprises diamictites, mudrocks, and sandstones with minor conglomerates. These lithologies are arranged in repetitive stacking patterns (cycles), interpreted to record repeated advance and retreat of glaciers into and out of the basin, with attendant eustatic and isostatic effects. Phases of ice retreat within the cycles comprise an array of mudrocks, …

Evolution With Depth From Detrital To Authigenic Smectites In Sediments From And-2a Drill Core (Mcmurdo Sound, Antarctica), Francesco Iacoviello, Giovanna Giorgetti, Fernando Nieto, Isabella Turbanti Memmi

ANDRILL Research and Publications

We have examined the nature and origin of smectites in glaciomarine sediments of the AND-2A drill core (McMurdo Sound, Antarctica) by means of X-ray diffraction (XRD) analyses on the clay fraction, field emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM) observations and SEM-EDS microanalyses on smectite particles. Relying on the smectite variation throughout the drill core it was possible to split the sequence into three units. Smectites throughout the core are either detrital or authigenic. Detrital smectites are close to montmorillonite-beidellite in composition while newly-formed smectites frequently have higher Fe-Mg contents and intermediate compositions between the saponite and nontronite …

Geogram 2011, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Policy And Science Of Geothermal Heat Use At Mcmurdo Station, Antarctica, Joe Alvine

Department of Environmental Studies: Undergraduate Student Theses

My thesis research project deals with the use of geothermal heat in Antarctica. Currently it is not allowed due to article 7 of the 1991 Protocol on Environmental Protection that placed a 50 moratorium on the exploitation of mineral resources. The US main base in Antarctica, McMurdo Station is currently powered by diesel generators that are inefficient, cause environmental damage, and is expensive to run. By exploring alternative energy options, McMurdo Station can reduce its dependence on non-renewable energy sources. By determining the geothermal potential of McMurdo Station, this project explores the possibilities and benefits that would occur with the …

Geogram 2010, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Comparison Of Ice Core Dissolved Organic Matter From A Greenland Ice Core By Nanospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Joshua Jeremiah Shiloh Marsh

Chemistry & Biochemistry Theses & Dissertations

Recent studies of ice cores have embarked on the task of determining the classes of dissolved organic matter (DOM) present in melt-water from the cores collected in numerous locations in the northern and southern hemispheres. This DOM originally derives from wet precipitation and is thought to reflect atmospheric organic matter derived from anthropogenic and non-anthropogenic sources. Because the amount of DOM is so low, previous studies have necessarily used large sample volumes (greater than 500 mL) to concentrate sufficient ice core DOM necessary for mass spectral analysis. Solid phase extraction (SPE) with C₁₈ resins was followed by evaporative concentration …

Geogram 2009, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Geogram 2008, David J. Keeling, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton

United States Geological Survey: Staff Publications

Loess is one of the most extensive surficial geologic deposits in mid-continental North America, particularly in the central Great Plains region of Nebraska. Last-glacial-age loess (Peoria Loess) reaches its greatest known thickness in the world in this area. New stratigraphic, geochronologic, mineralogic, and geochemical data yield information about the age and provenance of Peoria Loess, as well as evaluation of recent climate models.

Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Geogram 2006, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Guide To Participation For The Andrill Mcmurdo Ice Shelf Project, Andrill Science Management Office, Mcmurdo-Andrill Science Implementation Committee

ANDRILL Project Information

Purpose of This Document

This document is a guide to participation for science team members involved in the McMurdo Ice Shelf (MIS) Project of the ANDRILL Program. The document provides the following information: 1) An overview of the ANtarctic geologic DRILLing (ANDRILL) Program; 2) An overview of expected individual involvement in and commitment to the MIS Project; and 3) Logistical information most relevant to on-ice participants. Information provided in this document will be supplemented by the publication of the MIS Science and Logistics Implementation Plan (SLIP).The SLIP will be available to all MIS ANDRILL participants prior to commencement of drilling. …

Scientific Logistics Implementation Plan For The Andrill Mcmurdo Ice Shelf Project, Timothy R. Naish, Richard H. Levy, Ross D. Powell, Mis Science And Operations Team Members

ANDRILL Project Information

Summary

Response of Antarctic ice sheets to projected greenhouse warming of up to 5.8°C by the end of the century is unknown. Models on which predictions are based need to be constrained by geological proxy data from the ancient ice sheets during times when Earth is known to have been warmer than today. The marine-based West Antarctic Ice Sheet (WAIS) and its fringing ice shelves are hypothesized (Clark et al., 2002; Weaver et al., 2003; Stocker, 2003) and documented (Scherer et al., 1998) to have collapsed during past “super-interglacial” warm extremes when global sea-level was more than 5m higher than …

Geogram 2005, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Andrill Mcmurdo Ice Shelf Project Scientific Prospectus, Timothy R. Naish, Ross D. Powell, Peter J. Barrett, Huw Horgan, Gavin B. Dunbar, Gary S. Wilson, Richard Levy, Natalie Robinson, L. Carter, Alex R. Pyne, Frank Niessen, Stephen Bannister, Natalie Balfour, Detlef Damaske, Stuart Henrys, Phil Kyke, Terry Wilson

ANDRILL Project Information

Response of Antarctic ice sheets to projected greenhouse warming of up to 5.8!C by the end of the century is not known. Models on which predictions are based need to be constrained by geological data of the ancient ice sheets during times when Earth is known to have been warmer than today. The marine-based West Antarctic Ice Sheet (WAIS) and its fringing ice shelves are hypothesized (Clark et al., 2002; Weaver et al., 2003; Stocker, 2003) and documented (Scherer et al., 1998) to have collapsed during past “super-interglacial” warm extremes when global sea-level was more than 5m higher than today. …