Seismic Evidence for a Weak Basal Layer During The 1982 Surge of Variegated Glacier, Alaska, U.S.A

Glacier surge mechanism: 1982-1983 surge of variegated glacier, alaska.

The hundredfold speedup in glacier motion in a surge of the kind the kind that took place in Variegated Glacier in 1982-1983 is caused by the buildup of high water pressure in the basal passageway system, which is made possible by a fundamental and pervasive change in the geometry and water-transport characteristics of this system. The behavior of the glacier in surge has many remarkable featur...

Quantifying the Basal Conditions of a Mountain Glacier Using a Targeted Full-Waveform Inversion: Bench Glacier, Alaska, USA

Glacier dynamics are inextricably linked to the basal conditions of glaciers. Seismic reflection methods can image the glacier bed under certain conditions. However, where a seismically thin layer of material is present at the bed, traditional analyses may fail to fully characterize bed properties. We use a targeted full-waveform inversion algorithm to quantify the basal-layer parameters of a m...

Basal conditions and glacier motion during the winter/spring transition, Worthington Glacier, Alaska, U.S.A

Wav Es of Accelerated Motion in a Glacier Approaching Surge: the Mini-surges of Variegated

Periods of dramatically accelerated motion, in which the flow velocity increases suddenly from about 55 cm/d to a peak of 1 00-300 cm/d and then decreases gradually over the course of a day, occurred repeatedly during June and July 1 978-8 1 in Variegated Glacier (Alaska), a surging-type glacier that surged in 1 982-83. These "mini-surges" appear to be related mechanistically to the main surge....

Seasonal fluctuations in the advance of a tidewater glacier and potential causes: Hubbard Glacier, Alaska, USA

Satellite imagery has been used to acquire seasonal terminus positions of tidewater Hubbard Glacier, Alaska, USA, from 1992 to 2006. During this 15 year time period, the width-averaged advance of the entire terminus has been 620m at a mean rate of 35ma. Seasonal fluctuation of the terminus ranges from 150 to 200m on average and varies spatially. A section of the terminus, near a narrow gap wher...