Summary

In this section we were able to learn what implication erosion has on a grand scale. We learned the following:

1. The definition of mass wasting
2. The various types of mass wasting
3. The forces behind mass wasting
4. What humans are doing to aggravate the occurrence of mass wasting

Synthesis

In the opening section, we saw a video of an earthflow in Italy and the damage it caused. Can you imagine that coming down a mountain side towards a major city like this?

Figure 1. Damage from the debris flow on the Caraballeda fan. The main channel (at left) avulsed to a new course that led it through the houses to the right. These avulsion deposits are up to 6 meters (20 ft) thick and total about 1.8 million cubic meters of boulders and other material.

What about this?

Figure 2. The Mameyes mudflow disaster, in barrio Tibes, Ponce, Puerto Rico, was caused by heavy rainfall from Tropical Storm Isabel in 1985. The mudflow destroyed more than 100 homes and claimed an estimated 300 lives.

Back to the picture from the opening—did you notice anything odd about the trees in the picture? They were definitely shaped strangely at the base. Their trunks were curved. These trees are the result of mass wasting, specifically creep. Creep is the slowest form of mass wasting, but imagine what would happen if you had a house there!

Once again, we have seen strong forces we are dealing with in geology. By understanding how the various types of mass wasting occur, geologists can save not only money but lives as well.