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Erratic Boulders — Legacy of the Ice Age: Talk by Rick Thompson

  • PSU Cramer Hall 1721 Southwest Broadway Portland, OR, 97201 (map)

At the end of the Ice Age when the Lake Missoula Flood roared across the landscape, the floodwaters carried with it granite and other boulders. These rocks, referred to as erratics, were encased in the floating sections of the broken ice dam and distributed along the path of the mighty waters from Montana to the Pacific Ocean.  Many of them can be seen today.

Rick Thompson will discuss ice age floods around the world, show images of many erratics in the Portland/Willamette Valley areas; explain how to recognize an erratic, and tell about the ongoing hunt for these iceberg erratics.  

A native Oregonian, Mr. Thompson is President of the Lower Columbia Chapter of the Ice Age Floods Institute who loves to share the beauty of the great Northwest.  Mr. Thompson has become the local “go-to” person for the visible effects of the floods in NW Oregon and SW Washington.  He was on Grant McOmie’s Grant’s Getaways in 2012 and 2013 discussing the erratics in this area.  

An earlier planned talk on "Understanding the Western Margin of the United States" has been cancelled.