Picture Gorge, John Day Fossil Beds National Monument
This view of the Picture Gorge Basalt is exposed along Rock Creek (along Highway 26 about one mile west of the intersection of Highway 19). Stair step-like ledges represent individual flood basalt flows that formed over a period of time beginning about 16 million years ago in the region. Fossil soil profiles between the lava flows suggest quiet periods lasting several 10,000 to 100,000 years occurred between eruptions. During those intervals forest ecosystems redeveloped across the region (Fremd and others, 1994; USGS, 2010).
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Last modified: 12/20/2010