July 14, 1920 Traverse made from Canyon City to Seneca, Logan Valley, summit & Prairie City. Bretz Field Notes
A terse line from a survey notebook, and the flood evidence it set down.
Geologists now estimate that floodwaters pooled here to depths of 800 feet or more behind the Wallula Gap constriction. Rhythmite sequences in the basin sediments record dozens of separate flood events.
Active: 1914-1979 (primary IAF fieldwork 1922-1932; Penrose Medal 1979) Affiliation: University of Chicago (Instructor 1914, Professor 1926, retired 1947, emeritus through 1979) Key paper: Bretz, J H. (1923). "The Channeled Scabland of the Columbia Plateau." Journal of Geology 31(8): 617-649.
Bretz spent seven summer field seasons beginning in 1922 walking the basalt coulees, dry cataracts, and giant gravel bars of eastern Washington and concluded that the landscape required a catastrophic flood at a scale no existing process could produce. He coined the term "Channeled Scabland" in his 1923 paper and over the next decade defended the hypothesis against a uniformitarian geology establishment that had no plausible source for the water and viewed catastrophism as scientifically illegitimate. Bretz refused to name a source until Pardee's 1942 paper supplied one: Glacial Lake Missoula. He continued publishing on the scablands as an emeritus professor through the 1950s and 1960s, including his synthesis "Washington's Channeled Scabland" (1959). The Geological Society of America awarded him the Penrose Medal in 1979 at age 96; he reportedly remarked to his son, "All my enemies are dead, so I have no one to gloat over."
Source: J Harlen Bretz - Wikipedia; HistoryLink.org; University of Chicago Magazine
Flood-extent overlay shows the maximum reach of the Missoula Floods.
One of more than 1,800 surveyed sites. Plotted together, the field record is the map that proved the flood.
View on the interactive map Cinematic timeline · 3D flood · every captured siteA panorama from the spot the entry describes, looking out the way the surveyor saw it.
From the air, the feature in the note reads as part of the larger flood landscape it belongs to.
A photogrammetry model of a key specimen at the site, the evidence the line of notes rests on.