Zusammenfassung der Ressource
WATERFALL
- FLUVIAL EROSION
- Youthful Stage of a River
- 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
- Pollaphouca falls, river liffey, co wicklow