Questions Subject Area: Gravity’s Effect on Erosion and Deposition March 11, 2015 Subject Area: Gravity’s Effect on Erosion and Deposition EQ: How does landslides change human and wildlife habitats? Questions How is slope related to mass movement? How does gravity affect mass movement? What are the different types of mass movement?

Gravity’s Effect on Erosion and Deposition What are some of the agents of erosion and deposition we have already learned about? We have learned about rivers, waves, wind, and ice. Another agent of erosion and deposition that is constantly at work on the Earth’s surface is Gravity

Mass Movement Mass movement is the movement of any material such as rock, soil, or snow. Mass movement is controlled by the force of gravity and can occur rapidly or slowly.

Forces in Mass Movement All mass movement occurs on slopes as a result of gravitational pull.

Angle of Repose The angle of repose is the steepest angle, or slope, at which loose material will not slide down-slope.

Angle of Repose Loose rock and sediment will not move unless the angle of the material is greater than the angle of repose.

Slope The steeper the slope is, the more likely it is that mass movement will occur. What factors increase the potential for mass movement? Response: The factors that increase potential mass movement are …

Rapid Mass Movement Rapid mass movement occurs when material, such as rock and soil, moves down-slope quickly. Rapid mass movement can be very dangerous, destroying everything in its path.

Rock Fall A rock fall happens when a group of loose rock falls down a steep slope.

Land Slide A landslide is the sudden and rapid movement of a large amount of material down-slope.

Slump A slump is an example of a landslide. A slump occurs when a block of material moves down-slope on a curved surface.

Mudflow A mudflow is a rapid movement of a large mass of mud. Mudflows can carry trees, houses, cars, and other objects that lie in its path.

Lahars Mudflows of volcanic origin are called Lahars. Lahars can move at speeds more than 80 km/hr and are as thick as concrete.

Slow Mass Movement Slow mass movement happens a little at a time and more material can be moved collectively over time.

Creep The extremely slow movement of material down-slope is called creep. Water will break up rock, roots, pry rocks apart, and small animals will burrow in the ground contributing to creep.

Summary Answer the essential question “How does landslides change human and wildlife habitats?” Your answer needs to be in complete sentences. Place your answer at the bottom of the notes we did today. Make sure you include the different types of mass movement. Use your notes to get the answers.

Erosion: Landslide What did you know? _____________________________________________ 2. What did you learn? 3. What do you want to know?

Homework Chapter 11, Section 4 in the purple workbook. This is found on pages 89 – 90.

February 11, 2014 Agenda Roll PowerPoint titled: Gravity’s Effect on Erosion and Deposition Possible Video