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In this active seismic experiment we will collect AVO data at two glacier sites. One is located over a glacier bed high and the other one over a depression. The goals is to use Amplitude vs Offset methods to determine the nature of the subglacial material. A line of 24 geophones will be buried in snow to protect them from wind noise and the line will be accurately surveyed with GPS. A set of 100 shot holes will be drilled into the underlying ice to obtain a large range of offsets, so that amplitudes can be compared over large offset angles. If possible, the data will also be used to find the thickness of a subglacial till layer. The seismic experiment is part of a large geophysical and remote sensing observational program with the goal to provide input data for an ice flow model that will explore possible future scenarios for this large glacier that is very vulnerable to future climate change. In a second experiment we will do attempt to measure the extent of buried ice in the glacier foreland. For this experiment we propose to use 4.5 Hz geophones and we will use a hammer for the active source. This is part of the same NSF funded work.