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Collecting glacial moraine boulder samples

Detailed Description

This is an example of a boulder that is part of a glacial deposit in the southern Sawatch Mountains of Colorado. The moraine slopes down to the left side of the frame; this slope is modified from teh original depositional shape of the moraine deposit. A NAGT student intern is using a Brunton compass clinometer to measure the inclination of hte horizon above horizontal. This information is needed to calculate the exposure age of the boulder using cosmogenic beryllium-10. The ages of glacial landforms like this moraine are determined as part of larger geologic mapping efforst in the region, which characterize surface materials, and is used by land and resource managers. Numeric ages from landforms like this moraine provide constraint on the timing of past glacial retreat, which can help constrain teh rates of fault slip, and contribute to our understanding of Quaternary landscape evolution. 


Public Domain.