Journal Title
Title of Journal:
|
Abbravation: Quaternary Research
|
Publisher
Cambridge University Press
|
|
|
|
|
|
Authors: Ronald L Shreve
Publish Date: 1985/01
Volume: 23, Issue: 1, Pages: 27-37
Abstract
Values of the gradient of the former ice surface can be inferred at points along a flow line from deviations of esker paths or transitions in esker type and numerically integrated to give the profile A profile calculated in this way shows that during formation of the Katahdin esker system about 12700 yr ago the ice thickness at distances of 10 20 50 100 and 140 km from the terminus which is about two thirds of the distance to the ice divide was approximately 200 300 600 750 and 900 m The terminal reach was computed by assuming an unknown uniform basal drag and matching the profile to its known elevation at the terminus and known gradient 10 km upglacier Correction for isostatic rebound based on the elevations of contemporaneous deltas and of the marine limit proved unnecessary because the tilt due to the difference in uplift at the two ends of the profile is only 01 m km−1 With other plausible assumptions as to sea levels in the past elevations of the marine limit or exact location of the terminus the profile could be as much as roughly 100 m higher It hits Mount Katahdin about 500 m below its summit which is at 1600 m in agreement with the geological evidence farther west The steepening of the upper part of the profile suggests that the mountain dammed and diverted the ice Basal drag computed from the profile varies from about 20 kPa 02 bar near the terminus to 30 kPa 03 bar at 100 km to 70 kPa 07 bar at 140 km The relatively low values away from the influence of Mount Katahdin agree with independent evidence from deepsea cores of substantial late Wisconsin icesheet thinning without comparable areal reduction The method has potential for application over wide areas that were occupied by the Laurentide and Scandinavian ice sheets
Keywords:
References
citation title=Water pressure in intra and subglacial channels citation author=Röthlisberger H citation publication date=1972 citation journal title=Journal of Glaciology citation volume=11 citation firstpage=177 citation lastpage=203 citation doi=101017/S0022143000022188
.
|
Other Papers In This Journal:
- Ice-Sheet Glaciation of the Puget Lowland, Washington, during the Vashon Stade (Late Pleistocene) 1
- The Timing of Late Pleistocene Mammalian Extinctions in North America
- An Altitudinal Cline in Tropical African Grass Floras and Its Paleoecological Significance
- Glaciations of the West Coast Range, Tasmania
- Tephrochronology of Late Wisconsin Deglaciation and Holocene Glacier Fluctuations Near Glacier Peak, North Cascade Range, Washington
- Determining the Exposure Age of a Karst Landscape
- Stable Isotope Stratigraphy of a Late Last Interglacial Speleothem from Rana, Northern Norway
- Holocene Paleoenvironmental Change in the Kenyan Central Rift as Indicated by Micromammals from Enkapune Ya Muto Rockshelter
- Paleoecological Studies at Lake Patzcuaro on the West-Central Mexican Plateau and at Chalco in the Basin of Mexico 1
- Some Effects of Partial Recrystallisation on 14 C dating Late Pleistocene Corals and Molluscs
- Some Effects of Partial Recrystallisation on 14 C dating Late Pleistocene Corals and Molluscs
- Climate Variation and the Rise and Fall of an Andean Civilization
- Saharan Dust Transport and High-Latitude Glacial Climatic Variability: The Alboran Sea Record
- Pedogenic Gradients for Iron and Aluminum Accumulation and Phosphorus Depletion in Arctic and Alpine Soils as a Function of Time and Climate
- Glacial-Marine Sedimentation and Quaternary Glacial History of Marguerite Bay, Antarctic Peninsula
- QUA volume 31 issue 1 Cover and Front matter
- Paleoclimatic Significance of the Stable Isotopic Composition and Petrology of a Late Pleistocene Stalagmite from Botswana
- Mass Balance and Sliding Velocity of the Puget Lobe of the Cordilleran Ice Sheet During the Last Glaciation
- Tephrochronology of the Western Gulf of Mexico for the Last 185,000 Years
- Is There Evidence for Solar Forcing of Climate in the GISP2 Oxygen Isotope Record?
- Plio-Pleistocene Marine-Continental Correlation using Habitat Indicators from Olduvai Gorge, Tanzania
- Late Weichselian Marine 14 C Reservoir Ages at the Western Coast of Norway
- Late-Glacial and Early Holocene Environmental and Climatic Change at Lake Tambichozero, Southeastern Russian Karelia
- The Late Wisconsinan Savanna Terrace in Tributaries to the Upper Mississippi River
- The Late Wisconsinan Savanna Terrace in Tributaries to the Upper Mississippi River
- Optical Dating of Holocene Dune Sands in the Ferris Dune Field, Wyoming
- Fire and Vegetation History from the Coastal Rain Forest of the Western Oregon Coast Range
- Alluvial Pollen on the North China Plain
- Vegetation, Climate, and Sea Level in the Past 55,000 Years, Hanjiang Delta, Southeastern China
- Aspartic Acid Racemization in Late Wisconsin Lake Ontario Sediments
- The Classic Marine Isotope Substage 5e
- Mire Development and Environmental Change, Barrington Tops, New South Wales, Australia
- Significance of Two New Pleistocene Plant Records from Western Europe
- Lake Tapps Tephra: An Early Pleistocene Stratigraphic Marker in the Puget Lowland, Washington
- Modern and Holocene Pollen Assemblages from Some Small Arctic Lakes on Somerset Island, NWT, Canada
- Toward the Definition of Criteria for the Recognition of Artificial Bone Alterations 1
- Late Weichselian and Holocene Relative Sea-level History of Bröggerhalvöya, Spitsbergen
- A Comparison of Radiolarian and Foraminiferal Paleoecology in the Southern Indian Ocean: New Evidence for the Interhemispheric Timing of Climatic Change
|