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Articles 1 - 24 of 24
Full-Text Articles in Physical Sciences and Mathematics
Basal Melting Along The Floating Part Of Byrd Glacier, James P. Kenneally, Terence J. Hughes
Basal Melting Along The Floating Part Of Byrd Glacier, James P. Kenneally, Terence J. Hughes
Earth Science Faculty Scholarship
A mass balance calculation was made for the floating part of Byrd Glacier, using 1978-79 ice elevation and velocity data, over the 45 km of Byrd Glacier from its grounding line to where it leaves its fjord and merges with the Ross Ice Shelf. Smoothed basal melting rates were relatively uniform over this distance and averaged 12 +/- 2 m yr(-1).
Fracture And Back Stress Along The Byrd Glacier Flowband On The Ross Ice Shelf, James P. Kenneally, Terence J. Hughes
Fracture And Back Stress Along The Byrd Glacier Flowband On The Ross Ice Shelf, James P. Kenneally, Terence J. Hughes
Earth Science Faculty Scholarship
East Antarctic ice discharged by Byrd Glacier continues as a flowband to the calving front of the Ross Ice Shelf. Flow across the grounding line changes from compressive to extensive as it leaves the fjord through the Transantarctic Mountains occupied by Byrd Glacier. Magnitudes of the longitudinal compressive stress that suppress opening of transverse tensile cracks are calculated for the flowband. As compressive back stresses diminish, initial depths and subsequent growth of these cracks, and their spacing, are calculated using theories of elastic and ductile fracture mechanics. Cracks are initially about one millimeter wide, with approximately 30 in depths and …
Polar Mm5 Simulations Of The Winter Climate Of The Laurentide Ice Sheet At The Lgm, David H. Bromwich, E. Richard Toracinta, Helin Wei, Robert J. Oglesby, James L. Fastook, Terence J. Hughes
Polar Mm5 Simulations Of The Winter Climate Of The Laurentide Ice Sheet At The Lgm, David H. Bromwich, E. Richard Toracinta, Helin Wei, Robert J. Oglesby, James L. Fastook, Terence J. Hughes
Earth Science Faculty Scholarship
Optimized regional climate simulations are conducted using the Polar MM5, a version of the fifth-generation Pennsylvania State University-NCAR Mesoscale Model (MM5), with a 60-km horizontal resolution domain over North America during the Last Glacial Maximum (LGM, 21 000 calendar years ago), when much of the continent was covered by the Laurentide Ice Sheet (LIS). The objective is to describe the LGM annual cycle at high spatial resolution with an emphasis on the winter atmospheric circulation. Output from a tailored NCAR Community Climate Model version 3 (CCM3) simulation of the LGM climate is used to provide the initial and lateral boundary …
Variations In Ice Rafted Detritus On Beaches In The South Shetland Islands: A Possible Climate Proxy, Brenda L. Hall, Ethan R. Perry
Variations In Ice Rafted Detritus On Beaches In The South Shetland Islands: A Possible Climate Proxy, Brenda L. Hall, Ethan R. Perry
Earth Science Faculty Scholarship
Raised beach ridges on Livingston Island of the South Shetland Islands display variations in both quantity and source of ice rafted detritus (IRD) received over time. Whereas the modem beach exhibits little IRD, all of which is of local origin, the next highest beach (similar to250 C-14 yr BP) has large amounts, some of which comes from as far away as the Antarctic Peninsula. Significant quantities of IRD also were deposited similar to 1750 C-14 yr BP. Both time periods coincide with generally cooler regional conditions and, at least in the case of the similar to250 yr old beach, local …
Sea Level Pressure Variability Over The Southern Indian Ocean Inferred From A Glaciochemical Record In Princess Elizabeth Land, East Antarctica, Cunde Xiao, Paul Andrew Mayewski, Dahe Qin, Zhongqin Li, Mingjun Zhang, Yuping Yan
Sea Level Pressure Variability Over The Southern Indian Ocean Inferred From A Glaciochemical Record In Princess Elizabeth Land, East Antarctica, Cunde Xiao, Paul Andrew Mayewski, Dahe Qin, Zhongqin Li, Mingjun Zhang, Yuping Yan
Earth Science Faculty Scholarship
A 250-year, high-resolution, multivariate ice core record from LGB65 (70degrees50'07"S, 77degrees04'29"E; 1850 m asl), Princess Elizabeth Land (PEL), is used to investigate sea level pressure (SLP) variability over the southern Indian Ocean (SIO). Empirical orthogonal function (EOF) analysis reveals that the first EOF (EOF1) of the glaciochemical record from LGB65 represents most of the variability in sea salt throughout the 250-year record. EOF1 is negatively correlated (95% confidence level and higher) to instrumental mean sea level pressure (MSLP) at Kerguelen and New Amsterdam islands, SIO. On the basis of comparison with NCEP/NCAR reanalysis, strong correlations were found between sea-salt variations …
El Nino Suppresses Aantarctic Warming, Nancy A.N. Bertler, Peter J. Barrett, Paul Andrew Mayewski, Ryan L. Fogt, Karl J. Kreutz, James Shulmeister
El Nino Suppresses Aantarctic Warming, Nancy A.N. Bertler, Peter J. Barrett, Paul Andrew Mayewski, Ryan L. Fogt, Karl J. Kreutz, James Shulmeister
Earth Science Faculty Scholarship
Here we present new isotope records derived from snow samples from the McMurdo Dry Valleys, Antarctica and re-analysis data of the European Centre for Medium-Range Weather Forecasts (ERA-40) to explain the connection between the warming of the Pacific sector of the Southern Ocean [Jacka and Budd, 1998; Jacobs et al., 2002] and the current cooling of the terrestrial Ross Sea region [Doran et al., 2002a]. Our analysis confirms previous findings that the warming is linked to the El Nino Southern Oscillation (ENSO) [Kwok and Comiso, 2002a, 2002b; Carleton, 2003; Ribera and Mann, 2003; Turner, 2004], and provides new evidence that …
A Record Of Atmospheric Co2 During The Last 40,000 Years From The Siple Dome, Antarctica Ice Core, Jinho Ahn, Martin Wahlen, Bruce L. Deck, Ed J. Brook, Paul Andrew Mayewski, Kendrick C. Taylor, James W.C. White
A Record Of Atmospheric Co2 During The Last 40,000 Years From The Siple Dome, Antarctica Ice Core, Jinho Ahn, Martin Wahlen, Bruce L. Deck, Ed J. Brook, Paul Andrew Mayewski, Kendrick C. Taylor, James W.C. White
Earth Science Faculty Scholarship
We have measured the CO2 concentration of air occluded during the last 40,000 years in the deep Siple Dome A ( hereafter Siple Dome) ice core, Antarctica. The general trend of CO2 concentration from Siple Dome ice follows the temperature inferred from the isotopic composition of the ice and is mostly in agreement with other Antarctic ice core CO2 records. CO2 rose initially at similar to 17.5 kyr B. P. ( thousand years before 1950), decreased slowly during the Antarctic Cold Reversal, rose during the Younger Dryas, fell to a local minimum at around 8 kyr B. P., and rose …
Association Between Atmospheric Circulation Patterns And Firn-Ice Core Records From The Inilchek Glacierized Area, Central Tien Shan, Asia, Vladimir B. Aizen, Elena M. Aizen, John M. Melack, Karl J. Kreutz, L. Dewayne Cecil
Association Between Atmospheric Circulation Patterns And Firn-Ice Core Records From The Inilchek Glacierized Area, Central Tien Shan, Asia, Vladimir B. Aizen, Elena M. Aizen, John M. Melack, Karl J. Kreutz, L. Dewayne Cecil
Earth Science Faculty Scholarship
Glacioclimatological research in the central Tien Shan was performed in the summers of 1998 and 1999 on the South Inilchek Glacier at 5100 - 5460 m. A 14.36 m firn-ice core and snow samples were collected and used for stratigraphic, isotopic, and chemical analyses. The firn-ice core and snow records were related to snow pit measurements at an event scale and to meteorological data and synoptic indices of atmospheric circulation at annual and seasonal scales. Linear relationships between the seasonal air temperature and seasonal isotopic composition in accumulated precipitation were established. Changes in the delta(18)O air temperature relationship, in major …
Impact Of Preindustrial Biomass-Burning Emissions On The Oxidation Pathways Of Tropospheric Sulfur And Nitrogen, B. Alexander, J. Savarino, Karl J. Kreutz, M. H. Thiemens
Impact Of Preindustrial Biomass-Burning Emissions On The Oxidation Pathways Of Tropospheric Sulfur And Nitrogen, B. Alexander, J. Savarino, Karl J. Kreutz, M. H. Thiemens
Earth Science Faculty Scholarship
Ice core measurements (H2O2 and CH4/HCHO) and modeling studies indicate a change in the oxidation capacity of the atmosphere since the onset of the Industrial Revolution due to increases in fossil fuel burning emissions [e. g., Lelieveld et al., 2002; Hauglustaine and Brasseur, 2001; Wang and Jacob, 1998; Staffelbach et al., 1991]. The mass-independent fractionation (MIF) in the oxygen isotopes of sulfate and nitrate from a Greenland ice core reveal that biomass-burning events in North America just prior to the Industrial Revolution significantly impacted the oxidation pathways of sulfur and nitrogen species deposited in Greenland ice. This finding highlights the …
Catastrophic Ice Shelf Breakup As The Source Of Heinrich Event Icebergs, Christina L. Hulbe, Douglas R. Macayeal, George H. Denton, Johan Kleman, Thomas V. Lowell
Catastrophic Ice Shelf Breakup As The Source Of Heinrich Event Icebergs, Christina L. Hulbe, Douglas R. Macayeal, George H. Denton, Johan Kleman, Thomas V. Lowell
Earth Science Faculty Scholarship
Heinrich layers of the glacial North Atlantic record abrupt widespread iceberg rafting of detrital carbonate and other lithic material at the extreme-cold culminations of Bond climate cycles. Both internal (glaciologic) and external ( climate) forcings have been proposed. Here we suggest an explanation for the iceberg release that encompasses external climate forcing on the basis of a new glaciological process recently witnessed along the Antarctic Peninsula: rapid disintegrations of fringing ice shelves induced by climate-controlled meltwater infilling of surface crevasses. We postulate that peripheral ice shelves, formed along the eastern Canadian seaboard during extreme cold conditions, would be vulnerable to …
Surface Deformations As Indicators Of Deep Ebullition Fluxes In A Large Northern Peatland, P. H. Glaser, J. P. Chanton, P. Morin, D. O. Rosenberry, D. I. Siegel, O. Ruud, L. I. Chasar, Andrew S. Reeve
Surface Deformations As Indicators Of Deep Ebullition Fluxes In A Large Northern Peatland, P. H. Glaser, J. P. Chanton, P. Morin, D. O. Rosenberry, D. I. Siegel, O. Ruud, L. I. Chasar, Andrew S. Reeve
Earth Science Faculty Scholarship
Peatlands deform elastically during precipitation cycles by small (+/- 3 cm) oscillations in surface elevation. In contrast, we used a Global Positioning System network to measure larger oscillations that exceeded 20 cm over periods of 4 - 12 hours during two seasonal droughts at a bog and fen site in northern Minnesota. The second summer drought also triggered 19 depressuring cycles in an overpressured stratum under the bog site. The synchronicity between the largest surface deformations and the depressuring cycles indicates that both phenomena are produced by the episodic release of large volumes of gas from deep semi-elastic compartments confined …
Dating The Siple Dome (Antarctica) Ice Core By Manual And Computer Interpretation Of Annual Layering, Kendrick C. Taylor, Richard B. Alley, Debra A. Meese, Matthew K. Spencer, Ed J. Brook, Nelia W. Dunbar, Robert C. Finkel, Anthony J. Gow, Andrei V. Kurbatov, Gregg W. Lamorey, Paul Andrew Mayewski, Eric A. Meyerson, Kunihiko Nishiizumi, Gregory A. Zielinski
Dating The Siple Dome (Antarctica) Ice Core By Manual And Computer Interpretation Of Annual Layering, Kendrick C. Taylor, Richard B. Alley, Debra A. Meese, Matthew K. Spencer, Ed J. Brook, Nelia W. Dunbar, Robert C. Finkel, Anthony J. Gow, Andrei V. Kurbatov, Gregg W. Lamorey, Paul Andrew Mayewski, Eric A. Meyerson, Kunihiko Nishiizumi, Gregory A. Zielinski
Earth Science Faculty Scholarship
The Holocene portion of the Siple Dome (Antarctica) ice core was dated by interpreting the electrical, visual and chemical properties of the core. The data were interpreted manually and with a computer algorithm. The algorithm interpretation was adjusted to be consistent with atmospheric methane stratigraphic ties to the GISP2 (Greenland Ice Sheet Project 2) ice core, (BE)-B-10 stratigraphic ties to the dendrochronology C-14 record and the dated volcanic stratigraphy. The algorithm interpretation is more consistent and better quantified than the tedious and subjective manual interpretation.
Ice Dynamics Preceding Catastrophic Disintegration Of The Floating Part Of Jakobshavn Isbrie, Greenland, Jesse V. Johnson, Paul R. Prescott, Terence J. Hughes
Ice Dynamics Preceding Catastrophic Disintegration Of The Floating Part Of Jakobshavn Isbrie, Greenland, Jesse V. Johnson, Paul R. Prescott, Terence J. Hughes
Earth Science Faculty Scholarship
The floating terminal of Jakobshavn Isbr ae, the fastest Greenland ice stream, has disintegrated since 2002, resulting in a doubling of ice velocity and rapidly lowering inland ice elevations. Conditions prior to disintegration were modeled using control theory in a plane-stress solution, and the Missoula model of ice-shelf flow. Both approaches pointed to a mechanism that inhibits ice flow and that is not captured by either approach. Jamming of flow, an inherent property of granular materials passing through a constriction (Jakobshavn Isfjord), is postulated as the mechanism. Rapid disintegration of heavily crevassed floating ice accompanies break-up of the ice jam.
A 200 Year Sub-Annual Record Of Sulfate In West Antarctica, From Sixteen Ice Cores, D. Dixon, Paul Andrew Mayewski, S. Kaspari, Sharon B. Sneed, M. Handley
A 200 Year Sub-Annual Record Of Sulfate In West Antarctica, From Sixteen Ice Cores, D. Dixon, Paul Andrew Mayewski, S. Kaspari, Sharon B. Sneed, M. Handley
Earth Science Faculty Scholarship
Sixteen high-resolution ice-core records from West Antarctica and South Pole are used to examine the spatial and temporal distribution of sulfate for the last 200 years. The preservation of seasonal layers throughout the length of each record results in a dating accuracy of better than 1 year based on known global-scale volcanic events. A dual transport source for West Antarctic sea-salt (ss) SO42- and excess (xs) SO42- is observed: lower-tropospheric for areas below 1000m elevation and mid-/upper-tropospheric/stratospheric for areas located above 1000m. Our XsSO(4)(2-) records with volcanic peaks removed do not display any evidence of an anthropogenic impact on West …
A 700 Year Record Of Southern Hemisphere Extratropical Climate Variability, Paul Andrew Mayewski, Kirk A. Maasch, J W.C. White, E. J. Steig, E. Meyerson, I. Goodwin, V. I. Morgan, T. Van Ommen, M. A.J. Curran, J. Souney, Karl Kreutz
A 700 Year Record Of Southern Hemisphere Extratropical Climate Variability, Paul Andrew Mayewski, Kirk A. Maasch, J W.C. White, E. J. Steig, E. Meyerson, I. Goodwin, V. I. Morgan, T. Van Ommen, M. A.J. Curran, J. Souney, Karl Kreutz
Earth Science Faculty Scholarship
Annually dated ice cores from West and East Antarctica provide proxies for past changes in atmospheric circulation over Antarctica and portions of the Southern Ocean, temperature in coastal West and East Antarctica, and the frequency of South Polar penetration of El Nino events. During the period (AD) 1700-1850, atmospheric circulation over the Antarctic and at least portions of the Southern Hemisphere underwent a mode switch departing from the out-of-phase alternation of multi-decadal long phases of EOF1 and EOF2 modes of the 850 hPa field over the Southern Hemisphere (as defined in the recent record by Thompson and Wallace, 2000; Thompson …
Climate Variability In West Antarctica Derived From Annual Accumulation-Rate Records From Itase Firn/Ice Cores, Susan D. Kaspari, Paul Andrew Mayewski, Daniel A. Dixon, Vandy Blue Spikes, Sharon B. Sneed, Michael J. Handley, Gordon S. Hamilton
Climate Variability In West Antarctica Derived From Annual Accumulation-Rate Records From Itase Firn/Ice Cores, Susan D. Kaspari, Paul Andrew Mayewski, Daniel A. Dixon, Vandy Blue Spikes, Sharon B. Sneed, Michael J. Handley, Gordon S. Hamilton
Earth Science Faculty Scholarship
Thirteen annually resolved accumulation-rate records covering the last similar to 200 years from the Pine Island-Thwaites and Ross drainage systems and the South Pole are used to examine climate variability over West Antarctica. Accumulation is controlled spatially by the topography of the ice sheet, and temporally by changes in moisture transport and cyclonic activity. A comparison of mean accumulation since 1970 at each site to the long-term mean indicates an increase in accumulation for sites located in the western sector of the Pine Island-Thwaites drainage system. Accumulation is negatively associated with the Southern Oscillation Index (Sol) for sites near the …
Monsoonal Circulation Of The Mcmurdo Dry Valleys, Ross Sea Region, Antarctica: Signal From The Snow Chemistry, Nancy A.N. Bertler, Paul Andrew Mayewski, Peter J. Barrett, Sharon B. Sneed, Michael J. Handley, Karl J. Kreutz
Monsoonal Circulation Of The Mcmurdo Dry Valleys, Ross Sea Region, Antarctica: Signal From The Snow Chemistry, Nancy A.N. Bertler, Paul Andrew Mayewski, Peter J. Barrett, Sharon B. Sneed, Michael J. Handley, Karl J. Kreutz
Earth Science Faculty Scholarship
McMurdo Dry Valleys (MDV, Ross Sea region, Antarctica) precipitation exhibits extreme seasonality in ion concentration, 3-5 orders of magnitude between summer and winter precipitation. To identify aerosol sources and investigate causes for the observed amplitude in concentration variability, four snow pits were sampled along a coast-Polar Plateau transect across the MDV. The elevation of the sites ranges from 50 to 2400 m and the distance from the coast from 8 to 93 km. Average chemistry gradients along the transect indicate that most species have either a predominant marine or terrestrial source in the MDV. Empirical orthogonal function analysis on the …
Stratigraphic Continuity In 400 Mhz Short-Pulse Radar Profiles Of Firn In West Antarctica, Steven A. Arcone, Vandy Blue Spikes, Gordon S. Hamilton, Paul Andrew Mayewski
Stratigraphic Continuity In 400 Mhz Short-Pulse Radar Profiles Of Firn In West Antarctica, Steven A. Arcone, Vandy Blue Spikes, Gordon S. Hamilton, Paul Andrew Mayewski
Earth Science Faculty Scholarship
We track dated firn horizons within 400 MHz short-pulse radar profiles to find the continuous extent over which they can be used as historical benchmarks to study past accumulation rates in West Antarctica. The 30-40 cm pulse resolution compares with the accumulation rates of most areas. We tracked a particular set that varied from 30 to 90 m in depth over a distance of 600 km. The main limitations to continuity are fading at depth, pinching associated with accumulation rate differences within hills and valleys, and artificial fading caused by stacking along dips. The latter two may be overcome through …
Topographic Control Of Regional Accumulation Rate Variability At South Pole And Implications For Ice-Core Interpretation, Gordon S. Hamilton
Topographic Control Of Regional Accumulation Rate Variability At South Pole And Implications For Ice-Core Interpretation, Gordon S. Hamilton
Earth Science Faculty Scholarship
Snow-accumulation rates are known to be sensitive to local changes in ice-sheet surface slope because of the effect of katabatic winds. These topographic effects can be preserved in ice cores that are collected at non-ice-divide locations. The trajectory of an ice-core site at South Pole is reconstructed using measurements of ice-sheet motion to show that snow was probably deposited at places of different surface slope during the past 1000 years. Recent accumulation rates, derived from shallow firn cores, vary along this trajectory according to surface topography, so that on a relatively steep flank mean annual accumulation is similar to 18% …
Sulfur Isotopic Measurements From A West Antarctic Ice Core: Implications For Sulfate Source And Transport, Lee E. Pruett, Karl J. Kreutz, Moire Wadleigh, Paul Andrew Mayewski, Andrei V. Kurbatov
Sulfur Isotopic Measurements From A West Antarctic Ice Core: Implications For Sulfate Source And Transport, Lee E. Pruett, Karl J. Kreutz, Moire Wadleigh, Paul Andrew Mayewski, Andrei V. Kurbatov
Earth Science Faculty Scholarship
Measurements of delta(34)S covering the years 1935-76 and including the 1963 Agung (Indonesia) eruption were made on a West Antarctic firn core, RIDSA (78.73 degrees S, 116.33 degrees W; 1740m a.s.l.), and results are used to unravel potential source functions in the sulfur cycle over West Antarctica. The delta(34)S values Of SO42- range from 3.1 parts per thousand to 9.9 parts per thousand. These values are lower than those reported for central Antarctica, from near South Pole station, of 9.3-18.1 parts per thousand (Patris and others, 2000). While the Agung period is isotopically distinct at South Pole, it is not …
Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy Blue Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski
Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy Blue Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski
Earth Science Faculty Scholarship
lsochronal layers in firn detected with ground-penetrating radar (GPR) and dated using results from ice-core analyses are used to calculate accumulation rates along a 100 km across-flow profile in West Antarctica. Accumulation rates are shown to be highly variable over short distances. Elevation measurements from global positioning system surveys show that accumulation rates derived from shallow horizons correlate well with surface undulations, which implies that wind redistribution of snow is the leading cause of this variability. Temporal changes in accumulation rate over 25-185 year intervals are smoothed to along-track length scales comparable to surface undulations in order to identify trends …
El Niño Suppresses Antarctic Warming, Nancy A. N. Bertler, Peter J. Barrett, Paul Andrew Mayewski, Ryan L. Fogt, Karl J. Kreutz, James Shulmeister
El Niño Suppresses Antarctic Warming, Nancy A. N. Bertler, Peter J. Barrett, Paul Andrew Mayewski, Ryan L. Fogt, Karl J. Kreutz, James Shulmeister
Earth Science Faculty Scholarship
Here we present new isotope records derived from snow samples from the McMurdo Dry Valleys, Antarctica and re-analysis data of the European Centre for Medium-Range Weather Forecasts (ERA-40) to explain the connection between the warming of the Pacific sector of the Southern Ocean [Jacka and Budd, 1998; Jacobs et al., 2002] and the current cooling of the terrestrial Ross Sea region [Doran et al., 2002a]. Our analysis confirms previous findings that the warming is linked to the El Niño Southern Oscillation (ENSO) [Kwok and Comiso, 2002a, 2002b; Carleton, 2003; Ribera and Mann …
Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy B. Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski
Variability In Accumulation Rates From Gpr Profiling On The West Antarctic Plateau, Vandy B. Spikes, Gordon S. Hamilton, Steven A. Arcone, Susan Kaspari, Paul Andrew Mayewski
Earth Science Faculty Scholarship
Isochronal layers in firn detected with ground-penetrating radar (GPR) and dated using results from ice-core analyses are used to calculate accumulation rates along a 100 km across-flow profile in West Antarctica. Accumulation rates are shown to be highly variable over short distances. Elevation measurements from global positioning system surveys show that accumulation rates derived from shallow horizons correlate well with surface undulations, which implies that wind redistribution of snow is the leading cause of this variability. Temporal changes in accumulation rate over 25-185 year intervals are smoothed to along-track length scales comparable to surface undulations in order to identify trends …
The Deglaciation Of Maine, Usa, Harold W. Borns Jr., Lisa A. Doner, Christopher C. Dorion, George L. Jacobson Jr., Michael R. Kaplan, Karl J. Kreutz, Thomas V. Lowell, Woodrow B. Thompson, Thomas K. Weddle
The Deglaciation Of Maine, Usa, Harold W. Borns Jr., Lisa A. Doner, Christopher C. Dorion, George L. Jacobson Jr., Michael R. Kaplan, Karl J. Kreutz, Thomas V. Lowell, Woodrow B. Thompson, Thomas K. Weddle
Earth Science Faculty Scholarship
The glacial geology of Maine records the northward recession of the Late Wisconsinan Laurentide Ice Sheet, followed by development of a residual ice cap in the Maine-Québec border region due to marine transgression of the St. Lawrence Lowland in Canada. The pattern of deglaciation across southern Maine has been reconstructed from numerous end moraines, deltas and submarine fans deposited during marine transgression of the coastal lowland. Inland from the marine limit, a less-detailed sequence of deglaciation is recorded by striation patterns, meltwater channels, scattered moraines and waterlain deposits that constrain the trend of the ice margin. There is no evidence …