Pleistocene megaflood landscapes of the Channeled Scabland

Victor Baker, Bruce N. Bjornstad, David R. Gaylord, Gary A. Smith, Scott E. Meyer, Petteri Alho, Roy M. Breckenridge, Mark R. Sweeney, Marek G Zreda

Research output: Chapter in Book/Report/Conference proceedingChapter

9 Scopus citations


The Channeled Scabland of east-central Washington comprises a complex of anastomosing fluvial channels that were eroded by Pleistocene megaflooding into the basalt bedrock and overlying sediments of the Columbia Plateau and Columbia Basin regions of eastern Washington State, U.S.A. The cataclysmic flooding produced huge coulees (dry river courses), cataracts, streamlined loess hills, rock basins, butte-and-basin scabland, potholes, inner channels, broad gravel deposits, and immense gravel bars. Giant current ripples (fluvial dunes) developed in the coarse gravel bedload. In the 1920s, J Harlen Bretz established the cataclysmic flooding origin for the Channeled Scabland, and Joseph Thomas Pardee subsequently demonstrated that the megaflooding derived from the margins of the Cordilleran Ice Sheet, notably from ice-dammed glacial Lake Missoula, which had formed in western Montana and northern Idaho. More recent research, to be discussed on this field trip, has revealed the complexity of megaflooding and the details of its history.

Original languageEnglish (US)
Title of host publicationExploring the Geology of the Inland Northwes
PublisherGeological Society of America
Number of pages73
ISBN (Electronic)9780813700410
StatePublished - Jan 1 2016

Publication series

NameGSA Field Guides


ASJC Scopus subject areas

  • Earth-Surface Processes
  • Geology
  • Palaeontology
  • Stratigraphy

Cite this

Baker, V., Bjornstad, B. N., Gaylord, D. R., Smith, G. A., Meyer, S. E., Alho, P., Breckenridge, R. M., Sweeney, M. R., & Zreda, M. G. (2016). Pleistocene megaflood landscapes of the Channeled Scabland. In Exploring the Geology of the Inland Northwes (pp. 1-73). (GSA Field Guides; Vol. 41). Geological Society of America.