Saturday, March 6, 2010
Oregon's geologic history
This fascinating site from the Oregon Department of Geology and Mineral Industries (ODGMI) showcases the geologic history of the state. This site explains the fundamentals of plate tectonics and then illustrates in 20 progressive maps the incremental stages of land formation within the boundaries of the state beginning 400 million years ago. This progression provides a clear overview of the accretive geologic history of the state.
The resource linked above is supplemented by this project seeking to understand the Missoula Floods. As this page of the ODGMI's site shows, there are some extensive deposits from the Missoula Floods in much of the Willamette Valley and along the Columbia Gorge in northern Gilliam, Morrow, and Umatilla counties.