Glaciology Commons^™

Toward The Significance Of Crevasse Orientation In Low And High Crevassed Regions On The Kennicott Glacier, Alaska, Usa, Claire A. Sturm

DePaul Discoveries

Supraglacial landforms serve as potential indicators of underlying bedrock morphology and glacier dynamics. The distribution and morphology of crevasses are closely associated with stress fields and ice-flow regimes, representing processes of stable glaciers, in contrast to their reduced occurrence in stagnant or receding ice masses. The orientation and density of crevasses influence a glacier’s ability to absorb solar energy, as they facilitate movement of meltwater down to subglacial rivers. Beyond the meltwater acting as a lubricant for basal sliding, the slope of the bedrock further impacts the local velocity and ice deformation of a glacier. The study of ice-fracturing mechanics …

Glacier Elevation Difference Data For The Conterminous U.S., Andrew G. Fountain, Bryce Allen Glenn, Christopher Mcneil, Brian Menounos

Geology Faculty Datasets

Historic and recent elevation data for the glaciers in the conterminous US were differenced to estimate glacier mass and volume change.

Historic glacier elevations were obtained from the USGS National Elevation Dataset (https://doi.org/10.15760/geology-data.04), a digitized product from the USGS 1:24,000 paper topographic maps that included the glacier extent (Gesch, 2007). Recent glacier elevations were derived from aerial lidar and from satellite radar. The lidar data were largely obtained from the USGS 3D Elevation Program (Stoker and Miller, 2022; US Geological Survey, 2024), and filtered by acquisition date using only those data collected between mid-summer and early autumn. The …

The Case For Ice Rises At Ross Bank Since The Middle Miocene, William Weber

LSU Master's Theses

Many tens of ice rises exist at the marine margins of the Antarctic Ice Sheet. Isle-type ice rises in particular are those where an ice shelf is pinned to an underlying submarine bank. Recent and ongoing studies show that Ross Bank, on the middle continental shelf of central Ross Sea, was the former site of an important Ross Ice Shelf ice rise during the advance and retreat of the West Antarctic Ice Sheet (WAIS) in the last glacial cycle. Ross Bank is a broad and anomalously shallow water platform whose crest rises to 170 m water depth. Despite their importance …

Using Grounded Iceberg Wake Patterns To Interpret Catastrophic Flood Events In Southcentral Alaska, Jana K. Macinnis

All Master's Theses

Catastrophic flood events such as landslide tsunamis and jökulhlaups in glaciated areas can transport and strand icebergs, which obstruct the flow of floodwaters and leave a unique and recognizable grounded iceberg wake pattern in the sediment surface. Grounded iceberg wake patterns (GIWs) were identified at the two study areas in Southcentral Alaska; the outwash plain of a 1967 landslide tsunami at the Grewingk Glacier and proglacial lake, and the Matanuska River valley which experienced an unrecorded jökulhlaup in recent geological times. From these sites, 110 GIWs were identified through visual interpretation of lidar imagery and characterized by measuring their geometry, …

Seismological Applications To Crustal Deformation And Explosion Discrimination, Olumide Adedeji

Earth and Planetary Sciences ETDs

There are many outstanding questions in seismology and plate tectonics that remain unresolved due to the complexity of seismic wave propagation, fault system evolution, and sedimentary-tectonic interactions. In this dissertation, I analyze seismic and acoustic data to improve event discrimination, understand strain partitioning along a transpressive plate boundary, and investigate the influence of tectonic deformation on sedimentary processes. Using seismic arrays, I assess the detectability of Ground Coupled Airwaves (GCA) generated by shallow borehole explosions and earthquakes, demonstrating that GCA detections are highly dependent on source type, environmental conditions and sensor distribution. Along the Queen Charlotte Plate Boundary, I analyze …

Degradation Of Martian Glacier-Like Forms In Relation To The Observed Evolution Of Emmons Glacier On Mount Rainier, Wa, Jose E. Jimenez

Electronic Theses, Projects, and Dissertations

This study establishes parallels between the observed degradational evolution of debris-covered glaciers on Mount Rainier, WA and select glacier-like forms (GLFs) by studying the time-varying morphologies of the debris cover. Mount Rainier is home to 28 debris-covered valley glaciers, including Emmons Glacier which has a history of orthoimages taken from 1951 to 2023 and high-resolution Digital Elevation Model (DEM) coverage of 2008, 2021 and 2022. We can observe the degradational evolution of Emmons Glacier through orthorectified black and white imagery collected from an airborne platform and the National Agricultural Imagery Program (NAIP) colored satellite images periodically collected over the last …

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.

Provenance Of Clastic Sedimentation In Middle Deadfall Lake And Paleoclimate Modelling Of Glacier Fluctuations At Mount Eddy, Eastern Klamath Mountains, California, Usa, Emily Stebbins

Cal Poly Humboldt theses and projects

This study reconstructs the timing, extent, and paleoclimate conditions associated with late Pleistocene glaciation in the Mount Eddy region of the eastern Klamath Mountains, northern California and investigates the provenance of clastic sedimentation in Middle Deadfall Lake, just east of Mt Eddy. Using a multi-pronged approach that combines geomorphic mapping, sediment core analysis, X-ray fluorescence (XRF) geochemistry, tephrochronology, and glacier modeling using PalaeoIce 2.0, this research provides new insights into glacial dynamics and climate variability in a region with limited glacially derived paleoclimate datasets, as well as past volcanic eruption deposits.

Field and GIS-based geomorphic mapping identified three generations …

Exploring Intraplate Seismicity In The Midwest, Alexa Fernández

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Intraplate seismicity represents a notable occurrence within the stable North American Craton. This research explores the potential sources of stresses that could reactivate older faults and influence seismic activity within this region. Among these sources, the enduring impact of the last glacial period is considered, which includes continued glacial isostatic adjustments (GIA). During GIA the lithosphere rebounds due to the retreating ice, and the forebulge caused by far-field flexure in response to the glacial load, collapses. This results in significant faulting, fracturing, and seismic activity associated with the deglaciation phase. The adjustment of the lithosphere manifests as both near surface …

Unboxing The Complicated Near Term Climatic And Geomorphic History Of Mars, Joshua Matthew Williams

Earth and Planetary Sciences ETDs

It has long been thought that glacial processes were unlikely within the tropical regions of Mars. However, growing evidence, including this work has identified and quantified relic glacial forms within the equatorial regions. These findings have major implications for understanding Martian climate history and its sensitivity to changes in insolation. As well, the presence of ice in the equatorial region of Mars has significant implications for the past global redistribution of the water ice in the Martian cryosphere. In this manuscript, I clarify and refine our understanding of the morphology of glacial features in the equatorial zone by applying novel …

Glacial Resource Analysis – Castner Glacier, Alaska, Logan Erichsen

SACAD: Scholarly Activities

Glaciers cover much of the 49th U.S. state of Alaska. While many of these are deep blues, just as many are “rock” glaciers which means the glacier is covered in sediment. This sediment can be transported many miles through the mountain ranges. With the current climate melting these glaciers they are receding. Sediment and rock samples can now be safely collected from different locations where glaciers have released sediment that was locked in the ice for an untold number of years. Much of the USGS data comes from the 1940’s through 1960’s due to the size and remoteness of Alaska. …

Evaluation Of The Slip History And Holocene Activity Of The Strawberry Fault, Grant County, Oregon, Andrew Dunning

Dissertations and Theses

Lidar topographic data for the Strawberry Mountains, Oregon has revealed youthful fault scarps that likely result from Holocene-age earthquakes. We have mapped 27 km of fault scarps striking roughly east-west across the northern foothills of the Strawberry Mountains (Strawberry Fault, SBF) and another scarp lineament striking north-south along the uppermost John Day River 10 km to the south. SBF scarps are aligned with the bedrock John Day Fault, a reactivated Miocene structure that is accommodating distributed extension north of the Basin and Range region. The Strawberry Mountains sit near the interface of the extensional Basin and Range province to the …

Observed And Modeled Moulin Heads In The Pâkitsoq Region Of Greenland Suggest Subglacial Channel Network Effects, Celia Trunz, Kristin Poinar, Lauren C. Andrews, Matthew D. Covington, Jessica Mejia, Jason Gulley, Victoria Siegel

Geosciences Faculty Publications and Presentations

In the ablation zone of land-terminating areas of the Greenland Ice Sheet, water pressures at the bed control seasonal and daily ice motion variability. During the melt season, large amounts of surface meltwater access the bed through moulins, which sustain an efficient channelized subglacial system. Water pressure within these subglacial channels can be inferred by measuring the hydraulic head within moulins. However, moulin head data are rare, and subglacial hydrology models that simulate water pressure fluctuations require water storage in moulins or subglacial channels. Neither the volume nor the location of such water storage is currently well constrained. Here, we …

Reducing Uncertainty In Sea-Level Rise Prediction: A Spatial-Variability-Aware Approach, Subhankar Ghosh, Shuai An, Arun Sharma, Jayant Gupta, Shashi Shekhar, Aneesh Subramanian

I-GUIDE Forum

Given multi-model ensemble climate projections, the goal is to accurately and reliably predict future sea-level rise while lowering the uncertainty. This problem is important because sea-level rise affects millions of people in coastal communities and beyond due to climate change's impacts on polar ice sheets and the ocean. This problem is challenging due to spatial variability and unknowns such as possible tipping points (e.g., collapse of Greenland or West Antarctic ice-shelf), climate feedback loops (e.g., clouds, permafrost thawing), future policy decisions, and human actions. Most existing climate modeling approaches use the same set of weights globally, during either regression or …

Inventory Of Glaciers And Perennial Snowfields Of The Conterminous Usa, Andrew G. Fountain, Bryce Glenn, Christopher Mcneil

Geology Faculty Publications and Presentations

This report summarizes an updated inventory of glaciers and perennial snowfields of the conterminous United States. The inventory is based on interpretation of mostly aerial imagery provided by the National Agricultural Imagery Program, US Department of Agriculture, with some satellite imagery in places where aerial imagery was not suitable. The inventory includes all perennial snow and ice features ≥ 0.01 km². Due to aerial survey schedules and seasonal snow cover, imageries acquired over a number of years were required. The earliest date is 2013 and the latest is 2020, but more than 73 % of the outlines were …

Grounding Line And Calving Front Retreat In Glomar Challenger Basin And Pennell Trough Of Ross Sea, Antarctica Reconstructed From Diatom Abundances And Assemblages, Jaren Bradford

LSU Master's Theses

Previous studies showed that West Antarctic Ice Sheet (WAIS) retreat from the Whales Deep Basin continental shelf edge in eastern Ross Sea was underway by 14.7 ± 0.4 cal kyr BP. Following an ice-shelf breakup at 12.3 ± 0.6 cal kyr BP, a calving cliff margin remained within 60 km of the shelf edge until 11.5 ± 0.3 cal kyr BP. McGlannan et al. (2017) inferred that an ice shelf reformed immediately during a subsequent rapid retreat. That interpretation of grounding-line retreat with an intact ice shelf is being reevaluated by Sivils (in prep.). Here, we conducted a similar synthesis …

Origin Of The Mega-Streamlined Morphology In Ne Africa And Arabia: Remote Sensing And Field-Based Investigations, Mohamed Samy Mohamed Elhebery

Dissertations

Mega-streamlined landforms on Earth and Mars have been attributed to aeolian, glaciogenic, fluvial, and tectonic processes. Identifying the forces that shaped these landforms is paramount for understanding landscape evolution and constraining paleo-climate models and ice sheet reconstructions. Exhumed Late Ordovician glacial deposits and landscape of the North Gondwana are reported here for the first time from SE Egypt. Using field and remote sensing (Advanced Land Observing Satellite [ALOS], Phased Array L-band Synthetic Aperture Radar (PALSAR) radar, multispectral Landsat TM datasets, and digital elevation models (DEMs) I mapped the distribution of the Late Ordovician glacial features (i.e. deposits and landforms) in …

Collapse Of The Bindschadler Ice Stream At 11.5 Cal Kyr Bp Via Marine Ice Cliff Instability, Anna Sivils

LSU Master's Theses

Previous studies of the Whales Deep Basin (WDB) outer continental shelf showed that the paleo-ice shelf fronting the Bindschadler Ice Stream broke up at 12.3 cal kyr BP. A calving cliff was subsequently maintained until at least 11.5 cal kyr BP. Slightly after that time, the grounding line rapidly retreated creating a 200 km embayment of grounded ice over the foredeepened middle continental shelf. The rapid opening of the embayment is recorded by a backstepping succession of small-scale morainal ridges on the middle continental shelf. The overlapping and end-to-end spacing of morainal ridges requires that the retreating grounding line experienced …

Unearthing Complexity: Tangible Histories Of Water And Earth, Alexis Violet

Masters Theses

Unearthing Complexity investigates conceptions of time and surface through geological stories of the water and earth. Building on theories of deep time, hydrofeminism, critical zones, and grounding, I hope to foster a deeper awareness of time scales other than our own and a more tangible understanding of the embodied experience of matter in the universe. Working toward a new literacy of the water and earth in which they are recognized as living, changing bodies to which we are inherently tied at a molecular level, the site of this multiscalar inquiry occurs in the coastal zones of the Narragansett Bay where …

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 …

Data From: The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic

Geology Faculty Datasets

A comprehensive mid-20th century inventory of glaciers and perennial snowfields (G&PS) was compiled for the American West, west of the 100° meridian. The inventory was derived from U.S. Geological Survey 1:24,000 topographic maps based on aerial photographs acquired during 35 years,1955–1990.

Datasets From: Application Of Aerial Insar To Measure Glacier Elevations, Bryce Glenn, Andrew G. Fountain, Delywn Moller

Geology Faculty Datasets

In September 2016 NASA flew an interferometric synthetic aperture radar (GLISTIN) over most of the glacier-covered regions of the coterminous USA for the purpose of mapping the surface elevation of the glaciers. Where multiple passes were flown over the same ground track, the data were mosaiced together to improve data coverage and elevation accuracy. These data are to be used with elevations collected by past and future efforts to calculate volume change of glaciers.

The data were the basis for:

Glenn, Bryce Allen, "Assessing Airborne Radar to Map Glacier Elevations in Alpine Terrain Including Estimated Glacier Volume Change …

Isotopic Signature Of Massive, Buried Ice In Eastern Taylor Valley, Antarctica: Implications For Its Origin, Christopher B. Gardner, Melisa A. Diaz, Devin F. Smith, Andrew G. Fountain, Joseph S. Levy, W. Berry Lyons

Geography Faculty Publications and Presentations

The coastal regions of the McMurdo Dry Valleys, Antarctica, contain deposits of the Ross Sea Drift, sedimentary material left from the Ross Sea ice sheet from the advance of the West Antarctic ice sheet during the Last Glacial Maximum. Much of this deposit is ice-cored, but data on the stable isotopic composition of water from this ice, which may contain a valuable climate archive, are sparse or incomplete. Widespread thermokarstic ground subsidence in this “coastal thaw zone” of the McMurdo Dry Valleys suggests that these potential records are rapidly being lost due to the melting of ground ice and permafrost. …

Detecting Upland Glaciation In Earth’S Pre-Pleistocene Record, Gerilyn S. Soreghan, Lily Pfeifer, Dustin E. Sweet, Nicholas G. Heavens

School of Earth & Environment Departmental Research

Earth has sustained continental glaciation several times in its past. Because continental glaciers ground to low elevations, sedimentary records of ice contact can be preserved from regions that were below base level, or subject to subsidence. In such regions, glaciated pavements, ice-contact deposits such as glacial till with striated clasts, and glaciolacustrine or glaciomarine strata with dropstones reveal clear signs of former glaciation. But assessing upland (mountain) glaciation poses particular challenges because elevated regions typically erode, and thus have extraordinarily poor preservation potential. Here we propose approaches for detecting the former presence of glaciation in the absence or near-absence of …

Evidence For An Early Saginaw Lobe Ice Retreat And Drainage Adjustments Across Southern Michigan, Usa, Nathan Erber

Dissertations

The Saginaw lobe of the Laurentide Ice Sheet (LIS), flowed out of Saginaw Bay, across Lower Michigan and into northern Indiana. As it retreated, the Saginaw lobe deposited the Sturgis moraine, a recessional moraine of the lobe in southern Michigan. Positioned to the west and east of the Saginaw lobe were the Lake Michigan and Huron-Erie lobes, respectively. These lobes retreated across the region asynchronously, with the Saginaw lobe retreating first. The asynchronous behavior of the lobes allowed for the Lake Michigan and Huron-Erie lobes to overprint and alter landscapes once occupied by the Saginaw lobe ice.

The Kalamazoo moraine, …

Quantitative Analysis Of The Maximum Rate And Minimum Duration For A 200 Km Stepwise Retreat Of The Bindschadler Ice Stream At ~11.5 Cal Kyr Bp, Matthew E Kratochvil

LSU Master's Theses

Small-scale morainal ridges on the middle continental shelf of the Whales Deep Basin partly record the rapid opening of a 200-km grounding line embayment slightly after ~11.5 cal kyr BP. The overlapping pattern of backstepped moraines indicates that the grounding line oscillated back and forth during the retreat. Published sediment fluxes were combined with new sediment volume mapping of the moraines to infer the rates at which the grounding line retreated. The analyses indicate that the rates of grounding line retreat on the eastern flank of the embayment ranged from ~490 m a^-1 to 1,300 m a^-1. …

Cosmogenic Ages Indicate No Mis 2 Refugia In The Alexander Archipelago, Alaska, Caleb K. Walcott, Jason P. Briner, James F. Baichtal, Alia J. Lesnek, Joseph M. Licciardi

Publications and Research

The late-Pleistocene history of the coastal Cordilleran Ice Sheet remains relatively unstudied compared to chronologies of the Laurentide Ice Sheet. Yet accurate reconstructions of Cordilleran Ice Sheet extent and the timing of ice retreat along the Pacific Coast are essential for paleoclimate modeling, assessing meltwater contribution to the North Pacific, and determining the availability of ice-free land along the coastal Cordilleran Ice Sheet margin for human migration from Beringia into the rest of the Americas. To improve the chronology of Cordilleran Ice Sheet history in the Alexander Archipelago, Alaska, we applied 10Be and 36Cl dating to boulders and glacially sculpted …

Late Quaternary Glacier Fluctuations At Picayune Lake, Northern California, Aidan Patrick Cowan

Cal Poly Humboldt theses and projects

The Klamath Mountains are a 233-km-long (north to south) mountain range located in northern California that shows extensive geomorphic evidence of Pleistocene glaciation. Within the Klamath’s there are many highland lakes, which record evidence of glacial deposition, one of which is Picayune Lake. Lake sediment data collected from Picayune Lake offers insights into the glaciation, and broader depositional history of the Picayune Lake Valley, as well as the climate history of the Klamath Mountains region. I measured magnetic susceptibility, loss on ignition, and grain size in sediment cores and used radiocarbon dating to determine a chronology of glacier fluctuations in …

Research Sites Get Closer To Field Camps Over Time: Informing Environmental Management Through A Geospatial Analysis Of Science In The Mcmurdo Dry Valleys, Antarctica, Stephen M. Chignell, Madeline E. Myers, Adrian Howkins, Andrew Fountain

Geology Faculty Publications and Presentations

As in many parts of the world, the management of environmental science research in Antarctica relies on cost-benefit analysis of negative environmental impact versus positive scientific gain. Several studies have examined the environmental impact of Antarctic field camps, but very little work looks at how the placement of these camps influences scientific research. In this study, we integrate bibliometrics, geospatial analysis, and historical research to understand the relationship between field camp placement and scientific production in the McMurdo Dry Valleys of East Antarctica. Our analysis of the scientific corpus from 1907–2016 shows that, on average, research sites have become less …

Late Pleistocene And Early Holocene Sea-Level History And Glacial Retreat Interpreted From Shell-Bearing Marine Deposits Of Southeastern Alaska, Usa, James F. Baichtal, Alia J. Lesnek, Risa J. Carlson, Nicholas S. Schmuck, Jane L. Smith, Dennis J. Landwehr, Jason P. Briner

Publications and Research

We leverage a data set of >720 shell-bearing marine deposits throughout southeastern Alaska (USA) to develop updated relative sea-level curves that span the past ~14,000 yr. This data set includes site location, elevation, description when avail-able, and 436 14C ages, 45 of which are published here for the first time. Our sea-level curves suggest a peripheral forebulge developed west of the retreating Cordilleran Ice Sheet (CIS) margin between ca. 17,000 and 10,800 calibrated yr B.P. By 14,870 ± 630 to 12,820 ± 340 cal. yr B.P., CIS mar-gins had retreated from all of southeastern Alaska’s fjords, channels, and passages. At …