lecture 14 Flashcards
oslo landslide
deadliest ladnslide in history
- started as a debri slide from previous deposits
- 35 residents buried, 43 killed, both debri and rock
precondition of oso landslide
toe of slope is unstable b/c inscision of river into valley
rain saturated and weakened soil making it heavy and less stable
analysis of pre 2014
lidar imagery revealed that an earlier, smaller landslide in 2006 also destabalized slope
- numerous scars and deposits
ground vibrations
generated and recorded by nearby seismic stations
- shows 2 stages of landslide
montecito mudflows
vegetation acted as hillside soil stabilizers, healthy topsoil has burrowing animals that raises porosity allowing rain to pass through
- vegetation removed by wildfires leaves ash and clay with less porosity and doesnt absorb water as well causing flooding
mt meager landslide
group of volcanic peaks in garibalid volcanic belt
- rock is weak from hydorthermal activity
- composite landslide started as rock fall then became avalanche then debris flow
seismometers of mt meager landslide
timing of landslide including initial impact, debris flow in capricorn creek and impact with meager creek