Landslides take place when dirt, pebbles, rocks and boulders slide
down a slope together. Sometimes these landslides are small, and
hardly noticeable. Other times however, they can be substantial,
involving the entire side of a mountain.
These destructive slides can be triggered by a number of
different causes. Often rain, which adds additional weight to the
side of a slope can cause slides. Other times they might be caused
by erosion, as the base of a slope is slowly removed by a stream,
weakening the entire side of the mountain.
As a slide progresses down a mountain slope, it can pick up
tremendous speed, and energy. Some slides have been reported to
travel at speeds approaching 200 miles per hour. The resulting
winds can be so forceful, that they are known to strip the leaves
off of surrounding trees. The momentum of falling material has been
known to cause some of the materials to roll several hundred feet
back up the other side of a valley.
The amount of material moved in a landslide can be tremendous. In
some cases this material is so substantial, that it is measured in
cubic miles. This much material falling across a stream, can be the
cause for the formation or a new natural lake.
From the posted coordinates, you can see a small number of much
less dramatic landslides to the north. These may have been caused
by earthquakes, but more likely by rain. The abundant revegetation
suggests that these are at least several years old.
Logging Requirements
1 - post of photo of yourself at the site
2 - send me the answers to the following questions: How many
landslides do you see? Compare the two closest ones. How does the
length of the landslide relate to the steepness of the slope?
Many thanks to TerryDad for helping me establish this
Earthcache!
Source & Photo:
- www.kidsgeo.com/geology-for-kids/0071-landslides.php
