WATERFALL

WATERFALL

1. FLUVIAL EROSION

   • Youthful Stage of a River

2. interruption in river profile, vertical drop

   • River meets band of soft rock after flowing over hard rock
     • >differential erosion, hydraulic action, abrasion
       • cuts downwards into soft rock, steepening gradient
         • falling water hitting soft rock forms PLUNGE POOL beneath fall
           • drop= extra velocity
           • falling water undercuts soft rock by hydraulic action= OVERHANG
             • HARD rock deeply undercut> collapses
               • repeated many times> headward erosion of waterfall
                 • waterfall retreats upstream > GORGE
                   • waterfall is temporary, headword erosion will result in developing regular profile
                   • NIAGARA FALLS= GORGE

3. Pollaphouca falls, river liffey, co wicklow

Bilder und Dateien der Mindmap