Study Guide Chapter 7 PDF

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Study guide from chapter for weekly quizzes and unit exams...

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Dakota Bartsch A01823843 Unit 2: Assignment 3

Exam 2 Study Guide: Part 3 Chapter 7: Mass Wasting Instructions: Use the chapter 7 reading and lecture materials to answer the following questions. Some questions have multiple parts so carefully read the questions and provide detailed and specific responses. Generally, the difference between a good grade and a poor grade on an assignment is based on whether or not the questions were answered completely. The purpose of this assignment is to test your understanding of course materials covered from Chapter 7. Additionally, this assignment doubles as Part 3 of the Exam 2 study guide. 1. Describe the four variables used to classify downslope movement. (1 pt) 1. Falling usually occurs on free faces of cliffs, rocks, trees, and debris fall through the air and form talus slopes. 2. Sliding includes soil and rocks sliding on a curved, tilted, or planar surface. 3. Flowing movements include avalanches, can be very slow movement of land, and can be wet, including many materials, the medium between a landslide and a water flood. 4. More than one of these is considered more complex, as mass wastes can change from one classification to another as they travel downward. 2. The stability of a slope can be assessed by determining the relationship between which two forces? Describe those forces. (1 pt) Driving and resisting forces. The driving force moves the land and earth materials down a slope, while resisting forces pull back and resist. Often, the weight of the material is the driving force, while the the shear strength of the materials resists the movement. 3. Describe the interacting variables that create unstable avalanche conditions. (1 pt) Avalanches become unstable because of the steepness of their slopes, stability of the snowpack, and the weather. These variables work together to compromise the angle of repose, which is the steepest angle that the snowy surface can hold. 4. What are the effects of landslides? (1 pt) Direct effects are the immediate losses of life, property, buildings, roads, trade and travel routes and changes in geography. Landslides can also cause other natural hazards, including flooding from blocked streams. 5. What are the natural service functions of landslides? (1 pt) Landslides change the environment, which can create new habitats and ecosystems both on land and in water. These changes in the typography unearth mineral deposits and can even reveal valuable minerals like gold and diamonds. 6. Describe the effects of humans on landslides. (1 pt)

Humans effect landslides by the changes they cause to the surface of the land. Though they would occur naturally in many cases, landslide hazards are increased by manmade things like residential and commercial developments, transportation systems, and resource use. Resource uses include timber harvesting, removing trees compromises the strength of the soil to hold itself on a slope, essentially humans can change the stability of the land surrounding them, encouraging landslides. 7. What surface features can be used to identify potential landslides? (1 pt) Wherever slopes are underneath weak earth materials, landslides are probable. Some indications include cracks on hillsides, areas of bare soil (where a small landslide has probably already occurred), piles of rocks at the bottom of cliffs, clear path running down a slope, layered exposed bedrock down a slope, or irregularity at the bottom of a slope. Each of these signify land movement in the past. 8. What are the main steps that can be taken to prevent/reduce landslides? (1 pt) Thoughtful engineering is necessary to prevent and reduce landslides. Drainage control diverts water to keep it from compromising the surface of a slope. Slopes can also be covered with a layer of cement to protect it from water. Grading up sides of slopes can increase their stability, this system reduces the driving forces from the top of the slope and adds to the resisting forces at the base. Slope supports are walls constructed around a slope providing support and water flow. 9. What are some human perceptions of landslide hazards? (1 pt) Humans assume that landslides will happen elsewhere, but never near them. They often ignore warnings of high risk because of the rarity of large landslides occurring. In many cases, it takes a disaster to educate people on the true risk. 10. What topographic conditions are prone to landslide hazards? (1 pt) Landslides can occur anywhere slopes exist. Mountainous areas are prone to landslides because of their slope, most landslides occur within the main mountain ranges....