Presentation on theme: "Mass Movement: What causes the different types of mass movement?"— Presentation transcript:
Mass Movement: What causes the different types of mass movement?
Erosion is the process by which natural forces move weathered rock & soil from one place to another.
What is the material moved by erosion called? sediment This may include pieces of rock or soil or the remains of plants or animals
Deposition happens where agents of erosion drop or lay down sediment. (The word ‘agents’ means the processes or ways that erosion occurs.)
Mass movement happens when gravity moves sediment downhill. Mass movement can be rapid or slow and is caused by gravity.
Landslides are the most destructive of the four types of mass movement. Describe: Rock & soil slides quickly down steep slopes Where does it happen? Where road builders cut through hills or mountains
Landslides h ttp://carletong.wordpress.com/2009/04/27/paybacksamother/
Mudflows are very dangerous. Describe: Water (as much as 60% of the flow), rock & soil moves rapidly downhill What may trigger it? Earthquake moveme nt
Slump occurs when one huge mass falls together. Describe: Mass of rock & soil suddenly slip down a slope in one huge mass What makes it happen? When water soaks the bottom of soil rich in clay
Slump Cartersville, Georgia
Creep is very slow movement. Describe: Barely noticeable, you eventually see the effects of the slow movement in telephone poles, fence posts & trees leaning at odd angles What causes creep? From freezing & thawing of H2O in cracked layers of rock beneath the soil
Creep geology/geo101/masswasting.html&usg=__NXT2vQd6NNlaYppssy5JkhmQtO8=&h=357&w=300&sz=33&hl=en&start=7&um=1&tbnid=T5WrN7Z S1oqFeM:&tbnh=121&tbnw=102&prev=/images%3Fq%3Dcreep%2Bmass%2Bmovement%26hl%3Den%26sa%3DN%26um%3D1 Bent tree trunk illustrating creep. National Zoo, Rock Creek Park, Washington, D.C.