INTRODUCTION
This module examines weathering and mass wasting. Topics includephysical weathering, chemical weathering, and mass wasting. While these topics may appear to be disparate, you will learn how they are inherently related.The modules start with four opening topics, or vignettes, which are found in the accompanying Google Earth file. These vignettes introduce basic concepts of the weathering and mass wasting. Some of the vignettes have animations, videos, or short articles that will provide another perspective or visual explanation for the topic at hand.After reading the vignette and associated links, answer the following questions. Please note that some links might take a while to download based on your Internet speed.
Expandthe INTRODUCTION folder and then check Topic 1: Introduction.
Read Topic 1:Introduction
Question 1: According to the website, which of the following factors influence the speed of landslides? (Check all that apply).
A. Slope of ground
B. Water content
C. Volume of debris
D. Time since last landslide
Read Topic 2: Weathering
Question 2: Other than the rock material, what are the two most important factors in chemical weathering?
A. Water and slope of land
B. Debris type and water
C. Slope of land and temperature
D. Water and temperature
Read Topic 3: Mass Wasting
Question 3: What does the presence of lichen on boulders tell scientists?
A. It tells us the parent material of the debris
B. It tells us the relative time of a mass wasting event
C. It tells us what the slope of the land used to be
D. It tells us what the moisture content was at the time of the mass wasting event.
Read Topic 4: Human Interaction
Question 4: What are the characteristics of areas generally considered to be safe from landslides? (Check all that apply)
A. On flat areas away from slopes
B. On hard, non-jointed bedrock that has not moved in the past
C. At the base of minor drainage hollows
D. At the top or along the nose of ridges, set back from the tops of slopes
Collapse and uncheck the INTRODUCTIONfolder.
GLOBAL PERSPECTIVE
Figure 1.The geography of weathering (Arbogast 2nd Ed.).
Double-click and selectGLOBAL PERSPECTIVE.
Figure 1 is a graph showing the dominant type of weathering based on annual precipitation and temperature. If a location has a mean annual temperature of 20°C and receives 190cm of precipitation yearly, you can plot these values (as denoted by the star) to see this location’s dominant weathering is strong chemical.
For Questions 5 to 8, type the location information provided into the Searchtab in Google Earth and pressEnter. When you arrive at your destination, use the chart in Figure 1, in conjunction with Google Earth, to answer each question. The mean annual temperature and precipitation are provided respectively, in the parentheses.
Question 5: What is the dominant weathering In Bangkok, Thailand (28°C, 145cm)?
A. Moderate chemical
B. Strong chemical
C. Moderate chemical with frost action
D. Very slight weathering
Question 6: What is the dominant weathering in New Delhi, India (25°C, 80cm)
A. Moderate chemical
B. Strong chemical
C. Moderate chemical with frost action
D. Strong physical
Question 7: What is the dominant weathering at 19°10’21.78″N, 96° 7’59.77″W (25°C, 236cm)?
A. Moderate chemical
B. Strong chemical
C. Moderate chemical with frost action
D. Strong physical
Question 8:What is the dominant weathering at 58°18’7.00″N,134°25’11.00″W (5°C, 140cm)?
A. Moderate chemical
B. Strong chemical
C. Moderate chemical with frost action
D. Strong physical
Collapse and uncheck the GLOBAL PERSPECTIVE folder.
Weathering
Double-click WEATHERING, and then double‑click Mechanical Weathering.
Identify the dominant type of mechanical weathering at the following locations. Use the photo links in Google Earth to help you identify the type.
Double-click Feature A and then clickFeature A photo.
Question 9:Identify mechanical weathering at Feature A:
A. Frost wedging
B. Frost heaving
C. Salt-crystal growth
D. Exfoliation
Double-click Feature B and then clickFeature B photo.
Question 10:Identify mechanical weathering at Feature B:
A. Frost wedging
B. Frost heaving
C. Salt-crystal growth
D. Exfoliation
Double-click Feature C and then click Feature C photo.
Question 11:Identify mechanical weathering at Feature C:
A. Frost wedging
B. Frost heaving
C. Salt-crystal growth
D. Exfoliation
Collapse theMechanical Weathering folder.
Double-click Chemical Weathering.
Double-click Feature D and then click Feature D photo.
Question 12:Identify chemical weathering at Feature D:
A. Hydrolysis
B. Carbonation
C. Oxidation
D. Spheroidal
Double-click Feature Eand then clickFeature E photo.
Question 13:Identify chemical weathering at Feature E:
A. Hydrolysis
B. Carbonation
C. Oxidation
D. Spheroidal
Double-click Feature F and then click Feature F photo.
Question 14:Identify chemical weathering at Feature F:
A. Hydrolysis
B. Carbonation
C. Oxidation
D. Spheroidal
Collapse theChemical Weathering folder.
MASS WASTING
Expand theMASS WASTING folder.
Double-click and selectFeature G.
Select the dominant type of mass wastingat Feature G.
Question 15: Feature G: ________
A. Slump
B. Solifluction
C. Landslide
D. Rockfall
Question 16:Why did you pick the answer you did in Question 15?
A. Because the image shows material that has rotated and moved down the slope along a concave plane relative to the surface.
B. Because the image shows where freeze-thaw processes result in lobes of soil moving gradually downslope.
C. Because the image shows the result of movement of soil and bedrock down a steep slope in response to gravity,
D. Because the image shows rocks that suddenly slid down a mountainside
Double-click and selectFeature H.
Select the dominant type of mass wasting at Feature H.
Question 17: Feature H: _______
A. Slump
B. Solifluction
C. Landslide
D. Rockfall
Question 18: Why did you pick the answer you did in Question 17
A. Because the image shows material that has rotated and moved down the slope along a concave plane relative to the surface.
B. Because the image shows where freeze-thaw processes result in lobes of soil moving gradually downslope.
C. Because the image shows the result of movement of soil and bedrock down a steep slope in response to gravity,
D. Because the image shows rocks that suddenly slid down a mountainside
Double-click and selectFeature I and examine the area in September 1998. Use the historical imagery slider and advance the timeline to March 2007.
Select the dominant type of mass wasting at Feature I.
Question 19: Feature I: ______
A. Slump
B. Solifluction
C. Landslide
D. Rockfall
Question 20: Why did you pick the answer you did in Question 19?
A. Because the image shows materialthat has rotated and moved down the slope along a concave plane relative to the surface.
B. Because the image shows where freeze-thaw processes result in lobes of soil moving gradually downslope.
C. Because the image shows the result of movement of soil and bedrock down a steep slope in response to gravity,
D. Because the image shows rocks that suddenly slid down a mountainside
Double-click and select Slope 1. Right click the title Slope 1, and then select Show Elevation Profile.
Place your cursor over the elevation profile chart and compute the slope of the lines. Recall that the equation for slope is RISE/RUN and that the units must be the same when dividing (that is, both in meters).
Question 21: What is the RISE (Elevation gain) in meters?
A. 738 meters
B. 190 meters
C. 46.7 meters
D. 25.4 meters
Question 22: What is the RUN of the line (Distance) in meters?
A. 738 meters
B. 190 meters
C. 46.7 meters
D. 25.4 meters
Question 23:Based on the answers in Questions 21 and 22, what is the average slope of the line?
A. 738 %
B. 190 %
C. 46.7 %
D. 25.4 %
Double-click and select Feature J. Examine the area in July 1998. Use the historical imagery slider and advance the timeline to February 2003.
Select the dominant type of mass wasting at Feature J.
Question 24: Feature J: ______
A. Slump
B. Debris flow
C. Mudflow
D. Soil Creep
Question 25: Why did you pick the answer you did in Question 24?
A. Because the images show materialthat has rotated and moved down the slope along a concave plane relative to the surface.
B. Because the images show the results of a rapidly flowing and extremely powerful mass of water, rocks, sediment, boulders, and trees.
C. Because the images show the results of a well-saturated and highly fluid mass of fine-textured sediment
D. Because the images show the result of a gradual downhill movement of soil,trees, and rocks due to the force of gravity.
Double-click and select Feature K.
Select the dominant type of mass wasting at Feature K.
Question 26: Feature K: ________
A. Slump
B. Debris flow
C. Mudflow
D. Soil Creep
Question 27: Why did you pick the answer you did in Question 26?
A. Because the images show materialthat has rotated and moved down the slope along a concave plane relative to the surface.
B. Because the images show the results of a rapidly flowing and extremely powerful mass of water, rocks, sediment, boulders, and trees.
C. Because the images show the results of a well-saturated and highly fluid mass of fine-textured sediment
D. Because the images show the result of a gradual downhill movement of soil, trees, and rocks due to the force of gravity.
Double-click and select Slope 2. Right click the title Slope 2, and then select Show Elevation Profile.
Place your cursor over the elevation profile chart and compute the slope of the lines. Recall that the equation for slope is RISE/RUN andthat the units must be the same when dividing (that is, both in meters).
Question 28: What is the RISE (Elevation gain) in meters?
A. 92.1 meters
B. 35.6 meters
C. 128 meters
D. 148 meters
Question 29: What is the RUN of the line (Distance) in meters?
A. 92.1 meters
B. 35.6 meters
C. 128 meters
D. 148 meters
Question 30:Based on the answers in Questions 28 and 29, what is the average slope of the line?
A. 92.1 meters ÷ 92.1 meters x 100% = 100%
B. 35.6 meters ÷ 92.1 meters x 100% = 38.6%
C. 128 meters ÷ 148 meters x 100% = 86.5%
D. 35.6 meters ÷ 128 meters x 100% = 27.8%
Question 31: Which mass wasting event do you expect to travel faster (Feature I or K)? Why?
A. Feature I because it is one of the fastest types of mass wasting
B. Feature K because it is one of the fastest types of mass wasting
C. Feature I because it is one of the slowest types of mass wasting
D. Feature K because it is one of the slowest types of mass wasting
