Ice Age Floods National Geologic Trail
Ice Age Floods National Geologic Trail
7/18/12 Ice was about 600' deep at mouth of Cache Creek. Handwriten notes Pardee Cursive Notes 6876-1
7/18/12 Ice was about 600' deep at mouth of Cache Creek. Handwriten notes Pardee Cursive Notes 6876-1— Pardee 1910-1940
This is one of more than 1,800 field sites cataloged in the early scabland surveys — the bedrock of the Ice Age Floods scientific record. The Bretz-era researchers walked the ground first; modern cosmogenic dating, LiDAR, and remote sensing have since extended and refined what they mapped.
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
Every site along the trail will receive the full Terrain360 capture treatment: ground-level 360° panoramas, drone aerial imagery, and photogrammetry-based 3D models that visitors can spin in their browser. This page reserves the slots; the imagery flows in as field capture completes.
Ground-level 360° panorama, every step along the feature, captured by Terrain360 field crews.
Drone flyovers reveal the geometry of catastrophe — ripple marks, gravel bars, and scour patterns invisible from the ground.
Photogrammetry and Gaussian-splat models let visitors rotate, measure, and inspect features in detail-page WebGL viewers.
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.