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Glaciology Commons

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Drill cores

Articles 1 - 3 of 3

Full-Text Articles in Glaciology

Ice Layers As An Indicator Of Summer Warmth And Atmospheric Blocking In Alaska, Eric P. Kelsey, Cameron P. Wake, Karl Kreutz, Erich Osterberg Jun 2010

Ice Layers As An Indicator Of Summer Warmth And Atmospheric Blocking In Alaska, Eric P. Kelsey, Cameron P. Wake, Karl Kreutz, Erich Osterberg

Dartmouth Scholarship

No abstract provided.


A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N.E. Spaulding, D.A. Meese, I. Baker, P.A. Mayewski Jan 2010

A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N.E. Spaulding, D.A. Meese, I. Baker, P.A. Mayewski

Dartmouth Scholarship

Firn microstructure is accurately characterized using images obtained from scanning electron microscopy (SEM). Visibly etched grain boundaries within images are used to create a skeleton outline of the microstructure. A pixel-counting utility is applied to the outline to determine grain area. Firn grain sizes calculated using the technique described here are compared to those calculated using the techniques of Gow (1969) and Gay and Weiss (1999) on samples of the same material, and are found to be substantially smaller. The differences in grain size between the techniques are attributed to sampling deficiencies (e.g. the inclusion of pore filler in the …


Effects Of Impurities And Their Redistribution During Recrystallization Of Ice Crystals, D. Iliescu, I. Baker Feb 2008

Effects Of Impurities And Their Redistribution During Recrystallization Of Ice Crystals, D. Iliescu, I. Baker

Dartmouth Scholarship

In order to examine the effects of solutes on recrystallization and subsequent grain growth in ice, both doped and undoped ice single crystals were extruded through a 120o equal-channel angular extrusion jig, in order to impart a large shear strain (~1.15). Upon subsequent annealing at –3o C, the original single crystals recrystallized, in most cases to a new single crystal with a different orientation. Increasing the solute concentration (for H2SO4 to ~200–300ppb, and for NaCl, KCl and MgSO4 to >5ppm) was found to significantly retard the growth and possibly, for H2SO4 …