Columbia River Basalt Group - Related to Cascade Volcanoes?

Massive lava flows covered much of the inland Northwest 17-6 million years ago. The Ice Age Floods "Missoula Floods" later cut deep coulees and channels into the basalt flows.
The basalt surged to the surface through fissures - like cracks in the bottom of a row boat. The stack of basalt layers is more than 2 miles thick at some locations. More than 300 lava flows erupted.
Cascade volcanoes (Rainier, St. Helens, Hood, etc.) are not related to the Columbia River Basalt flows - The chemistry does not match! The Columbia River Basalts flowed from fissures to the east.
The Columbia River Basalts are believed to be connected to the hotspot now under Yellowstone National Park. Photos, video and map are used to illustrate.
Geologist make comparison between Columbia River Basalts and lava basalt flows in Hawaii.

Columbia River Basalt slideshow at: http://www.youtube.com/watch?v=-AsG9-FTuos

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