2014 GSA Annual Meeting in Vancouver, British Columbia (19–22 October 2014)

Paper No. 93-3
Presentation Time: 8:35 AM

BERING GLACIER, ALASKA - A PRIMARY GOOGLE EARTH GEOLOGICAL DESTINATION


MOLNIA, Bruce F., U.S. Geological Survey, National Civil Applicatons Center, 562 National Center, 12201 Sunrise Valley Drive, Reston, VA 20192 and ANGELI, Kim M., National Civil Applications Center, U.S. Geological Survey (USGS), 562 National Center, Reston, VA 20192

There are many reasons why Bering Glacier, located in southcentral Alaska, adjacent to the Gulf of Alaska, is a must visit geoscience site on Google Earth’s virtual globe.

Geologically, Bering Glacier is the largest (~5,000 km2) and longest (~190 km) glacier in continental North America and Earth’s largest temperate surging glacier. During the 20th century, Bering Glacier surged about every 20 years. All observed surges included kilometers of ice displacement, resulting in terminus thickening and rapid advance. In subsequent years, this was followed by rapid terminus retreat and thinning. The 21st century’s first surge, with a maximum terminus advance of 3.5 km, began in 2008 and continued through September 2011. Since then, Bering Glacier has been retreating.

Geographically, Bering Glacier covers ~ 6% of Alaska’s glacier-covered area and contains ~15% of Alaska’s glacier ice. Bering originates in Canada and flows northwest for 90 km through the fault-controlled Bagley Ice Valley before it turns to the southwest. It then flows 50 km through its wide central valley before merging with Steller Glacier to form a 50 km long piedmont lobe.

Geomorphologically, Bering displays many classical and unique glacial features. These including: ablation and accumulation zones, arête ridges, a calving tidewater terminus, cirques, multiple types of crevasses, a firn line, folded loop moraines, icebergs, several ice marginal lakes with abundant rock flour, kettles and thermokarst pits, medial and lateral moraines, nunataks, an outwash plain, vegetation-covered stagnant ice, and many others.

Visually, Google Earth imagery of Bering Glacier consists of combinations of Landsat imagery (15-30 m resolution), Digital Globe imagery (3-5 m resolution), and Global Fiducials Program (GFP) imagery (1 m resolution). The GFP imagery, which spans nearly a decade, includes the 2008-2011 surge. It is provided by the US Geological Survey. Other historical GFP imagery can be viewed by using the Historical Imagery option in the View tab on Google Earth’s Toolbar. GFP imagery can be used to examine the Mt. Steller Landslide which occurred in 2005. Mt. Steller is the highest peak adjacent to Bering’s piedmont lobe. Visit the GFP website (gfp.usgs.gov) for additional information about Bering Glacier and the GFP’s support of Google Earth.