Columbia Plateau, Columbia River Basalt Group
http://vulcan.wr.usgs.gov/Volcanoes/ColumbiaPlateau/framework.html

Cascades Volcano Observatory, USGS


This website features multiple links to geologic resources relating to the Columbia River Plateau and Columbia River Basalt Group. The types of resources available include background information, special items of interest, maps, graphics, images, and educational outreach for multiple levels of experience.

This resource is referenced here:
Subject: Geoscience:Geology:Igneous and Metamorphic Petrology:Volcanology
Resource Type: Scientific Resources:Collection
Topics: Solid Earth:Petrology:Volcanology