7/1/12 Pleistocene terraces Columbia & San Poil rivers. In vicinity of San Poil Ferry terraces developed on either side Col River at elev approx 100', 450' & 600' above the shores. Terraces flat topped are cut in a gravel with rather obscure horizontal bedding contains smooth to sub-ang cobbles up to 2' diam. Mostly granitoid & gneissoid. lenses of sand here & there. Terraces continue up San Poil valley. Handwriten notes Pardee Cursive Notes 6876-1
A terse line from a survey notebook, and the flood evidence it set down.
Pardee's identification of Glacial Lake Missoula as the source of Bretz's floods was the missing piece that ultimately convinced the geological community. His 1942 paper documenting giant current ripples proved the lake had drained catastrophically, not gradually.
Active: ~1909-1956 (USGS career; key Lake Missoula evidence 1910-1942) Affiliation: U.S. Geological Survey Key paper: Pardee, J.T. (1942). "Unusual currents in Glacial Lake Missoula, Montana." Geological Society of America Bulletin 53(11): 1569-1599.
Pardee grew up in a Montana mining family, opened an assay office out of college, and joined the USGS after a self-taught interest in geology became his career. He first proposed an ice-dammed glacial lake in the Missoula valley in 1910, decades before its connection to Bretz's scablands was made. His 1942 paper documented the giant current ripples on Camas Prairie - ridges 15 to 30 feet high with wavelengths around 250 feet - and demonstrated that they could only have formed under catastrophic outburst-flood velocities. That paper supplied the water source Bretz had refused to name and ended the formal Scabland Debate among working geologists, though broader acceptance took another two decades. Pardee died in Philipsburg, Montana in 1960 at age 88.
Source: Joseph Pardee - Wikipedia; GSA Today, Vol. 5 No. 9, 1995; hugefloods.com
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.
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