This great lava flow extends over a great part of Idaho, Washington, and Oregon. The area covered is extensive, some 200,000 square miles. That this flow has considerable depth may be seen at Shoshone Falls, and at various places where the river has cut a gorge. That there were successive flows with intervals of rest between may also be seen by a river gorge, for in the walls are fossil roots and stumps. Further than this but little has been written concerning this wonderful field.
Proceedings of the Iowa Academy of Science
©1903 Iowa Academy of Science, Inc.
Clearman, Harriet M.
"A Geological Situation in the Lava Flow, with Reference to the Vegetation,"
Proceedings of the Iowa Academy of Science, 11(1), 65-68.
Available at: https://scholarworks.uni.edu/pias/vol11/iss1/9