Aeolian activity in the south margin of the Tengger Desert in northern China since the Late Glacial Period revealed by luminescence chronology

AbstractThis work presents the first reconstruction of late Pleistocene glacier fluctuations on Uturuncu volcano, in the Southern Tropical Andes. Cosmogenic 3He dating of glacial landforms provides constraints on ancient glacier position between 65 and 14 ka. Despite important scatter in the exposure ages on the oldest moraines, probably resulting from pre-exposure, these 3He data constrain the timing of the moraine deposits and subsequent glacier recessions: the Uturuncu glacier may have reached its maximum extent much before the global LGM, maybe as early as 65 ka, with an equilibrium line altitude (ELA) at 5280 m. Then, the glacier remained close to its maximum position, with a main stillstand identified around 40 ka, and another one between 35 and 17 ka, followed by a limited recession at 17 ka. Then, another glacial stillstand is identified upstream during the late glacial period, probably between 16 and 14 ka, with an ELA standing at 5350 m. This stillstand is synchronous with the paleolake Tauca highstand. This result indicates that this regionally wet and cold episode, during the Heinrich 1 event, also impacted the Southern Altiplano. The ELA rose above 5450 m after 14 ka, synchronously with the Bolling–Allerod.

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The micromorphology of loess‐paleosol sequences in central Alaska: A new perspective on soil formation and landscape evolution since the Late Glacial period (c. 16,000 cal yr BP to present)

Geoarchaeology ◽

10.1002/gea.21807 ◽

2020 ◽

Vol 35 (5) ◽

pp. 701-728

Author(s):

Jennifer Kielhofer ◽

Christopher Miller ◽

Joshua Reuther ◽

Charles Holmes ◽

Ben Potter ◽

...

Keyword(s):

Landscape Evolution ◽

Soil Formation ◽

Late Glacial ◽

Glacial Period ◽

Late Glacial Period ◽

New Perspective

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Surface profiles and basal shear stresses of outlet glaciers from a Late-glacial mountain ice field in western Scotland

Journal of Glaciology ◽

10.3189/s0022143000042829 ◽

1991 ◽

Vol 37 (125) ◽

pp. 77-88 ◽

Cited By ~ 3

Author(s):

Peter W. Thorp

Keyword(s):

Late Glacial ◽

Shear Stresses ◽

Glacial Period ◽

Late Glacial Period ◽

Bedrock Topography ◽

Pore Water Pressures ◽

Basal Sliding ◽

Ice Field ◽

Surface Profiles ◽

Basal Shear

Abstract Surface and basal long profiles are reconstructed for 13 outlet glaciers that drained ice from a large ice field (80 km by 120 km) that formed in the western Grampians of Scotland during part of the Late-glacial period (c, 14000–10000years BP). Basal shear stresses are calculated at 5 km intervals along the central flowlines of the reconstructed outlet glaciers. Individual basal shear stresses for the outlet glaciers range from 10 to 204 kPa. Variations in calculated basal shear stresses within and between the glaciers are mainly explained by differences in bedrock topography, extending and compressional flow, and by differences in basal boundary conditions. Low basal shear stresses (<53kPa) calculated for the terminal zones of Creran, Menteith and Lomond glaciers are partly explained by the overriding of glaciomarine clays with inferred high pore-water pressures and a low yield strength that may have led to rapid basal sliding and thinning of the ice lobes.

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