Summary: | Glaciological studies initiated during the summer of 1960 on Gulkana Glacier in the central Alaska Range by members of the Department of Geology, University of Alaska, were continued during the summer of 1961. . The two-man field parties, each led by a graduate student of the University of Alaska, were in the field from June 1 to September 1. The two field parties made, respectively, a detailed ablation study and a study of the surface motion. . Larry Mayo led the party that concentrated on detailed mapping of ablation and accumulation, and recording local weather and net total radiation. Seventy-nine ablation poles and twenty-five snow pits were used to measure ablation and accumulation on the 3.5-mile-long glacier. Continuous weather observations were made for 3 months. The main weather station was located near the centre line of the glacier at an altitude of 4,800 feet. Every 12 hours measurements were made of wind, precipitation, and ablation on snow, ice, and morainal surfaces. Continuous records were made of temperature, humidity, and net total radiation. . A second weather station for continuous temperature measurements was at an altitude of 5,600 feet on the glacier. . Seventy-five of the ablation stakes were used in the surface motion study. This part of the program was led by Eugene Moores and consisted of the following: (1) an overall program of locating weekly, monthly, and bimonthly the position of all 75 stakes, (2) short-interval studies consisting of daily observations of seven stakes and 2-day observations of 32 stakes, (3) resurvey of the transverse profiles established in 1960, (4) extension of the triangulation net, and (5) locating stakes in the tributaries feeding the main ice streams. The short-interval studies concentrated on an area below the ice fall extending across the width of the glacier, including two stakes on different blocks at the top of the ice fall. Differential motion between ice streams was also investigated. . Gravity measurements were made along one longitudinal and three transverse lines on the glacier. .
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