The Great Missoula Floods

History of Lake Missoulahttp://nwcreation.net/articles/missoulaflood.htm

Interesting Facts• Volume: 2200 cubic Km (slightly larger than LakeErie and Ontario combined) Lake Bonneville 22,000 cubic km• Area: 7500 square Km• Depth: 700 m• Discharge: 17 million cubic m/s (would drain lakeErie in eight hours)• Velocity: up to 45 m/s (100mph)• Occurrence: at least 1 of abovemagnitudes (40 – 89 smaller floods)

Rainbow Lake2431www.mines.edu/academic/geology/faculty/klee/missoula.doc

Evidences of Lake MissoulaMt JumboShorelines

Mission Mountains near Flathead Lakehttp://www.pbs.org/wgbh/nova/megaflood/scab-nf.html

www.mines.edu/academic/geology/faculty/klee/missoula.doc

Ripples at Camas Prairie, MontanaAmplitude: up to 15mWavelength: up to 150mwww.mines.edu/academic/geology/faculty/klee/missoula.doc

Scablands, northeastern Washingtonwww.mines.edu/academic/geology/faculty/klee/missoula.doc

Main Channels of Flood123www.mines.edu/academic/geology/faculty/klee/missoula.doc

Dry FallsLargest water fall in the world 117m

“Colossal Cataract”www.mines.edu/academic/geology/faculty/klee/missoula.doc

Palouse Falls & Gorge56 m. tall120 m from top of falls to skylinewww.mines.edu/academic/geology/faculty/klee/missoula.doc

Multnomah FallsColumbia River GorgeMultnomah Falls in theColumbia River Gorgewas created whenfloodwaters incisedthe main canyon.www.mines.edu/academic/geology/faculty/klee/missoula.doc

DepositsPendant bar with ripples atconfluence of Palouse andSnake RiversFore-sets in bar dip 26 degreeswww.mines.edu/academic/geology/faculty/klee/missoula.doc

Erraticswww.mines.edu/academic/geology/faculty/klee/missoula.doc

ReferencesWeb siteshttp://www.iceagefloodsinstitute.org/trail.htmlhttp://imnh.isu.edu/digitalatlas/counties/bonner/misfld.htmhttp://nwcreation.net/articles/missoulaflood.htmhttp://192.211.16.13/curricular/energies/Aprojfolder/missoula/Title.htmhttp://www.iceagefloodsinstitute.org/http://www.pnl.gov/cms/program/flood.stmhttp://www.pbs.org/wgbh/nova/megaflood/fantastic.htmlhttp://www.pbs.org/wgbh/nova/megaflood/scab-nf.htmlhttp://rickandsidney.com/missoula_flood_research.htmhttp://students.washington.edu/dfinlays/classes/geology201/floodpres/img6.htmwww.mines.edu/academic/geology/faculty/klee/missoula.docwww.emporia.edu/earthsci/student/corley2/missoula.htmParfit, Michael. The floods That Carve the West. The Smithsonian.