Boulder Park National Natural Landmark, of Douglas County, Washington, along with the nearby McNeil Canyon Haystack Rocks and Sims Corner Eskers and Kames natural landmarks, illustrate well-preserved examples of classic Pleistocene ice stagnation landforms that are found in Washington. These landforms include numerous glacial erratics and haystack rocks that occur near and on the Withrow Moraine, which is the terminal moraine of the Okanogan ice lobe.[1][2]
- ^ Mueller, Marge & Ted (1997). Fire, Faults and Floods. University of Idaho Press, Moscow, Idaho. ISBN 0-89301-206-8.
- ^ Bjornstad, B., and Kiver, E., 2012, On the Trail of the Ice Age Floods: The Northern Reaches: A geological field guide to northern Idaho and the Channeled Scabland. Keokee Books, Sandpoint, Idaho. 480 pp. ISBN 978-1879628397