Glaciology Commons^™

Spring Thaw Ionic Pulses Boost Nutrient Availability And Microbial Growth In Entombed Antarctic Dry Valley Cryoconite Holes, Jon Telling, Alexandre M. Anesio, Martyn Tranter, Andrew G. Fountain, Thomas H. Nylen, Jon Hawkings, Virendra B. Singh, Preeti Kaur, Michaela Musilova, Jemma L. Wadham

Geology Faculty Publications and Presentations

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of spring thaw toward fully melted holes. The cryoconite holes had a mean isolation age from the glacial drainage system of 3.4 years, with an increasing mass of aqueous nutrients (dissolved organic carbon, total nitrogen, total phosphorus) with longer isolation age. During …

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

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Hyperspectral Measurements Of Wet, Dry And Saline Soils From The Mcmurdo Dry Valleys: Soil Moisture Properties From Remote Sensing, Joseph S. Levy, Anne Nolin, Andrew G. Fountain, James W. Head

Geology Faculty Publications and Presentations

Soil moisture is a spatially heterogeneous quantity in the McMurdo Dry Valleys of Antarctica that exerts a large influence on the biological community and on the thermal state of Dry Valleys permafrost. The goal of this project was to determine whether hyperspectral remote sensing techniques could be used to determine soil moisture conditions in the Dry Valleys. We measured the spectral reflectance factors of wetted soil samples from the Dry Valleys under natural light conditions and related diagnostic spectral features to surface layer soil moisture content. Diagnostic water absorption features in the spectra at 1.4 mu m and 1.9 mu …

Time, Money, And Melting Ice: Proposal For A Coopertive Study Of The World’S Cave Ice In A Race Against Climate Change, George Veni, Lewis Land, Aurel Perşoiu

The International Workshop on Ice Caves

Climate change is a global phenomenon that is melting and threatening to melt ice deposits in many of the world’s ice caves. The National Cave and Karst Research Institute of the USA is concerned that major and important paleoclimate and paleoenvironmental records stored in cave ice will soon be lost, and is proposing an international collaborative effort to overcome funding and logistical challenges to sample and analyze at least a representative collection of ice from several regions before further melting occurs.

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 …

Characterization Of Two Permanent Ice Cave Deposits In The Southeastern Alps (Italy) By Means Of Ground Penetrating Radar (Gpr), Renato R. Colucci, Daniele Fontana, Emanuele Forte

The International Workshop on Ice Caves

In order to assess the thickness and the inner structure of some permanent ice deposits in two high elevated alpine karstic caves of the Canin massif (Alpi Giulie, Italy), we performed several multi frequency Ground Penetrating Radar (GPR) surveys. The surveys have been conducted within the project MONICA (MOnitoring of Ice within Caves), aimed at the paleoclimatic characterization of the considered cave ice deposits. GPR surveys have proved to be crucial also in finding the most suitable place for carrying out a drilling core. This has been particularly useful in the Vasto’s ice cave (VIC) in which the direct/visual estimation …

New Research In Cave Ledenica In Bukovi Vrh On Velebit Mt In Croatian Dinaric Karst, Mladen Garasic

The International Workshop on Ice Caves

No abstract provided.

Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys, southern Victoria Land, East Antarctica, are a polar desert, and melt from glacial ice is the primary source of water to streams, lakes and associated ecosystems. Previous work found that to adequately model glacier ablation and subsurface ice temperatures with a surface energy-balance model required including the transmission of solar radiation into the ice. Here we investigate the contribution of subsurface melt to the mass balance of (and runoff from) Dry Valley glaciers by including a drainage process in the model and applying the model to three glacier sites using 13years of hourly meteorological data. Model …

Seismic And Geodetic Evidence For Grounding-Line Control Of Whillans Ice Stream Stick-Slip Events, Martin J. Pratt, J. Paul Winberry, Douglas A. Wiens, Sridhar Anandakrishnan, Richard B. Alley

All Faculty Scholarship for the College of the Sciences

The tidally modulated, stick‐slip events of Whillans Ice Stream in West Antarctica produce seismic energy from three locations near the grounding line. Using ice velocity records obtained by combining time series from colocated broadband seismometers and GPS receivers installed on the ice stream during the 2010–2011 and 2011–2012 austral summers, along with far‐field seismic recordings of elastic waves, we locate regions of high rupture velocity and stress drop. These regions, which are analogous to “asperities” in traditional seismic fault studies, are areas of elevated friction at the base of the ice stream. Slip events consistently initiate at one of two …

A Data Set Of Worldwide Glacier Length Fluctuations, Paul W. Leclercq, Johannes Oerlemans, Hassan J. Basagic, Christina Bushueva, A. J. Cook, Raymond Le Bris

Geology Faculty Publications and Presentations

Glacier fluctuations contribute to variations in sea level and historical glacier length fluctuations are natural indicators of past climate change. To study these subjects, longterm information of glacier change is needed. In this paper we present a data set of global long-term glacier length fluctuations. The data set is a compilation of available information on changes in glacier length worldwide, including both measured and reconstructed glacier length fluctuations. All 471 length series start before 1950 and cover at least four decades. The longest record starts in 1535, but the majority of time series start after 1850. The number of available …

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

Surficial Geologic Map Of Kings Canyon: Implications For Relatively Slow Stream Incision Rates, Andrew Farris

Natural Resources Management and Environmental Sciences

Most of the Kings River in the Sierra Nevada Mountains of California has responded to regional uplift with rapid incision, creating the deepest canyon in the United States. However, Kings Canyon near Cedar Grove is still a mountainous relict landscape with little evidence of fluvial incision. Mapping took place in the Cedar Grove area of Kings Canyon to assess factors and/or processes causing relatively low stream incision rates in the region during Holocene time. A surficial geologic map was created in the field, along with visual observations of the South Fork of the Kings River and characterization of geologic map …

Glacier Slip And Seismicity Induced By Surface Melt, Peter L. Moore, J. Paul Winberry, Neal R. Iverson, Knut A. Christianson, Sridhar Anandakrishnan, Miriam Jackson, Mark E. Mathison, Denis Cohen

All Faculty Scholarship for the College of the Sciences

Many of the key processes governing fast glacier flow involve interaction between a glacier and its basal hydrological system, which is hidden from direct observation. Passive seismic monitoring has shown promise as a tool for remotely monitoring basal processes, but lack of glacier-bed access prevents clear understanding of the relationships between subglacial processes and corresponding seismic emissions. Here we describe direct measurements of basal hydrology, sliding, and broadband seismicity made in a unique subglacial facility in Norway during the onset of two summer melt seasons. In the most pronounced of these episodes, rapid delivery of surface meltwater to the bed …

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

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Lithic Analysis Of Coyote Canyon Mammoth Site Sediments, Kaitlin M. Hill, George V. Last

STAR Program Research Presentations

The landforms and geologic layers of Southeastern Washington record fascinating, unique geologic events, including repeated catastrophic flooding that occurred during the last Ice Age. These floods left behind many distinctive features, and a variety of fossils. After discovery of mammoth-sized bones in 1999, and confirmation that more bones were still in place in 2008, the Coyote Canyon Mammoth Site near Kennewick, Washington was secured for research, and formal excavation began in 2010.

Previous research suggests that the remains are buried in Ice Age flood deposits, which are overlain by eolian sediments, and those in turn overlain by slope wash. We …

Grounding Zone Processes: Ice Mechanics And Margin Lakes, Kamb Ice Stream And Whillans Ice Stream, West Antarctica, Mason Joseph Fried

Dissertations and Theses

The lateral "corners" where Kamb and Whillans Ice Streams (KIS and WIS) discharge into the Ross Ice Shelf share common geometries and ice mechanical settings. At both corners of the now-stagnant KIS outlet, shear margins of apparently different ages confine regions with a relatively flat, smooth surface expression. These features are called the "Duckfoot" on the northern, right-lateral side and the "Goosefoot" on the other. It has been suggested, on evidence found in ice internal layers, that the flat ice terrains on KIS were afloat in the recent past, at a time when the ice stream grounding line was upstream …

Investigations Into The Regional And Local Timescale Variations Of Subglacial Drainage Networks, Justin Hiester

Dissertations and Theses

Subglacial water plays an important role in the regulation of an ice sheet's mass balance. It may be the dominant control on the velocities of ice streams and outlet glaciers on scales of months to millennia. Recent satellite observations of ice surface elevation changes have given researchers new insights into how subglacial water is stored and transported. Localized uplift and settling of the ice surface implies that lakes exist beneath the ice sheet that are being filled and drained on relatively short time scales. %At the base of an ice sheet water can be transported through a variety of drainage …

Examining Antarctica From A Geodynamic Perspective: Backstripping, Ice Thickness, Tectonics And Erosion, Travis Gary Hayden

Dissertations

I have applied the principles of basin analysis and geodynamics to several cores recovered from on or near the Antarctic continent to answer 2 independent questions about the tectonic evolution of Antarctica; as well as estimate the thickness of the Antarctic Ice Sheet at the Last Glacial Maximum.

I developed, and applied a modification of the backstripping modeling technique to compensate for the loading and erosion of glacial ice at the AND-1B site by combining a backstripping driven inverse model, with a driven ice-load model. This modification allowed me to identify and constrain the timing of major pulses of subsidence …

Rock Glaciers In The Eastern Cascades, Washington, Mark Weidenaar

Undergraduate Honors Theses

The eastern portion of Washington State's Cascade Range is a place not previously examined for rock glaciers, due to proximity to the Pacific Ocean and its associated marine-influenced climate. The objectives of this study were to determine spatial, activity, and genesis patterns, and paleoclimatic implications of Eastern Cascade rock glaciers. Using Google Earth, I found 103 rock glaciers in the study area. Rock glaciers are more common further east of the Cascade crest and more north in latitude, with the largest concentrations occurring east of Lake Chelan (22) and in the Pasayten Wilderness (28) in the North Cascades. None were …

Compressional And Em Wave Velocity Anisotropy In A Temperate Glacier Due To Basal Crevasses, And Implications For Water Content Estimation, John Bradford, Joshua Nichols, Joel T. Harper, Toby W. Meierbachtol

Geosciences Faculty Publications

We have conducted a series of experiments designed to investigate elastic and electromagnetic (EM) velocity anisotropy associated with a preferentially aligned fracture system on a temperate valley glacier in south-central Alaska, USA. Measurements include a three-dimensional compressional wave (P-wave) seismic reflection survey conducted over a 300 m x 300 m survey patch, with uniform source grid and static checkerboard receiver pattern. Additionally, we acquired a multiazimuth, multi-offset, polarimetric groundpenetrating radar (GPR) reflection experiment in a wagon-wheel geometry with 94 degrees of azimuthal coverage. Results show azimuthal variation in the P-wave normal-moveout velocity of less than 3% (3765 and 3630 ms …

Geologic Observations Along The Steamboat Trace Trail, Markers 16-20, In The Vicinity Of Peru, Nemaha County, Nebraska (Including On The Indian Cave Sandstone), Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

This section of the Steamboat Trace Trail from markers 16 through 20 (Figure 1) offers especially good examples of geologic features in this part of Nebraska (Figure 2). These include: The Missouri River, its valley, river cuts into the valley side, tributaries to the river, and flood control structures; Sites of active and potential landslides; Wind-deposited silts (called loess by geologists and soil scientists); Glacial deposits; Bedrock exposures of ancient sandstone, shale, conglomerate, and limestone; Fossils of ocean- and land-dwelling plants and animals; Coal deposits.

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 …

Instruments And Methods: A Method For Recording Ice Ablation Using A Low-Cost Ultrasonic Rangefinder, M. Len Keeler, Keith A. Brugger

Geology Publications

We have adapted inexpensive ultrasonic rangefinders to measure ablation rates on the surface of a glacier.While ultrasonic rangers are commercially available for this purpose, our goal was to utilize rangefinders typically used in hobby robotics without significantly compromising performance. To correct for environmental factors that affect the speed of sound we use two ultrasonic rangefinders, one focused on a fixed target. Measurements of ablation correlate well with manual measurements with an uncertainty of about 3 cm, suggesting an accuracy comparable with other non-manual methods of recording ablation. The limitations of our rangefinder include those inherent in commercially available units as …

Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya

Department of Earth, Environment and Sustainability Faculty Publications

Meltwater runoff modeling from glacierized basins needs several input data, including total meltwater contributing area. This study utilizes optical remote sensing data to assess glacierized basins in the central Himalayas where snow and glaciers contribute substantially to the water resources. Result shows that there are four main water-bearing zones in the basin: (a) dry snow, (b) wet snow, (c) exposed glacial ice, and (d) debris-covered glacial ice, and it is possible to differentiate and map these zones and their spatio-temporal variations from satellite sensor data. These zones can then be incorporated in meltwater runoff modeling as separate entities because they …

Applying Gis Metrics To Determine Degree Of Glacial Modification In Mountainous Landscapes, Carl Delbert Swanson Ii

All Master's Theses

The ability to quantitatively assess the degree of glaciation in mountainous areas can be a powerful tool in unraveling the evolution of landscapes, and provide key insights in regions where field research is difficult. Here we determine, test, and apply metrics that assess the relative degree of past glacial modification in mountainous landscapes. Results show that slope results can be used to quantitatively assess the degree to which an area is modified by glaciation. In particular, analysis of basins using slope frequency distribution curves and slope vs. elevation plots capture steeper slopes, flatter valley bottoms, cirques, and arêtes of glaciated …

Topographic Control Of Asynchronous Glacial Advances: A Case Study From Annapurna, Nepal, Beth Pratt-Sitaula, Douglas W. Burbank, Arjun M. Heimsath, Neil F. Humphrey, Michael Oskin, Jaakko Putkonen

All Faculty Scholarship for the College of the Sciences

Differences in the timing of glacial advances, which are commonly attributed to climatic changes, can be due to variations in valley topography. Cosmogenic 10Be dates from 24 glacial moraine boulders in 5 valleys define two age populations, late-glacial and early Holocene. Moraine ages correlate with paleoglacier valley hypsometries. Moraines in valleys with lower maximum altitudes date to the lateglacial, whereas those in valleys with higher maximum altitudes are early Holocene. Two valleys with similar equilibrium-line altitudes (ELAs), but contrasting ages, are < 5 km apart and share the same aspect, such that spatial differences in climate can be excluded. A glacial mass-balance cellular automata model of these two neighboring valleys predicts that change from a cooler-drier to warmer-wetter climate (as at the Holocene onset) would lead to the glacier in the higher altitude catchment advancing, while the lower one retreats or disappears, even though the ELA only shifted by ~120 m.

Linkages Between East Antarctic Ice Sheet Extent And Southern Ocean Temperatures Based On A Pliocene High‐Resolution Record Of Ice‐Rafted Debris Off Prydz Bay, East Antarctica, Sandra Passchier

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] Ice‐rafted debris mass accumulation rates (IRD MAR) at a drill site on the Antarctic continental margin are investigated to evaluate the linkages between East Antarctic Ice Sheet extent and Southern Ocean temperatures in the early to mid‐Pliocene. ODP Site 1165 is within 400 km of the Antarctic coastline and in the direct pathway of icebergs released by the Amery Ice Shelf. The Amery Ice Shelf is the largest ice shelf in East Antarctica and it buttresses the Lambert Glacier drainage system, which accounts for 14% of the outflow from the East Antarctic Ice Sheet. IRD MAR were low during …

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

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.