1. Timeline of recent Ice Ages (use the green arrows at the top and bottom to interact).
2. Virtual Glacier (select green links to interact)
3. Glacier Re-photography of the American West (select one of the red boxes and then red dots to view the collection)
Photo: Grinnell Glacier from Mt. Gould in Glacier National Park - Courtesy of the USGS
Speaking of glaciers . . .
Contrary to popular belief, the glaciers in Glacier National Park are NOT remnants of the last ice age that ended roughly 10,000 years ago. There is little doubt that ice age glaciers WERE responsible for carving the majestic peaks and valleys of the park (horns, cirques, aretes, hanging valleys, etc.), but experts believe those glaciers completely melted away during an especially warm period 9,000 to 5,000 years ago (Holocene Climate Maximum). On the other hand, glaciers present in the park today formed during a more recent cold period called "The Little Ice Age" (not a true "ice age") - a cold period that lasted from 1550 to 1850. According to evidence from moraines, tree rings, layers of volcanic ash (Mazama, etc.), and radiometric dating, these "Little Ice Age glaciers" formed in cirques that had been carved by glaciers during the last REAL ice age(s). To learn more about this AND to find out about the glacier that has formed in the crater of Mt. St. Helens, CLICK HERE.
Interested in a summer workshop in Glacier Park? Check out these offerings from the Glacier Institute I plan to take the course titled "Geology of Glacier: A Walk Through Earth's History".
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