(Internet exercise from Prof. Stephen A. Nelson Tulane University)

  1. The web site at
  2. shows the National Landslide Hazards Map, published by the U.S. Geological Survey.   This is a map of the lower 48 states showing areas where there have been a high incidence of landslides, and areas that have a high susceptibility to landslides.  Notice that you can click on various dots on the map and map legend to get an enlargement of various areas or the legend of the map.  On the large map, the areas colored in red are areas where there is a high incidence of landslides (covering greater than 15% of the area).  There are three major zones where high incidence of landslides occur. (1) near the west coast in the states of California, Oregon, and Washington, (2) in the Rocky Mountain states of Colorado, Utah, and Wyoming, and (3) in the Appalachian mountain states of Ohio, Pennsylvania, Virginia, West Virginia, Kentucky, Tennessee, and Georgia.  Surrounding these areas are areas of high to moderate susceptibility to landslides.

a.       For each of these three areas that have high incidence or susceptibility to landslides, what geologic features are present that contribute to the high incidence or susceptibility to landslides?  In answering this question, think about the major factors involved in landslides (the role of gravity, especially slope angle, the role of water, the role of different geological materials like soil and rock, and the presence of processes that trigger landslides.



    1. Click on the yellow dot just north of Louisiana to get an enlarged view of the southeastern United States.  Notice that there are zones running roughly north-south near the left-hand side of the map that show moderate and high susceptibility to landslides (buff and pink colored zones).  Notice that this band runs through the city of Memphis, Tennessee.  For a view of what Memphis looks like (before they built all of the buildings and planted trees)
      and for a more modern view click HERE  

      What reasons can you give that these areas are moderately to highly susceptible to landslides? (use the same criteria you used in part a, above)



    1. Find as near as possible the area where you live. What zone do you live in (answer by first stating exactly where you live, then by indicating the color zone on the map and the meaning of the color zone from the map legend)?  If it is a zone with a moderate to high incidence of landslides or a zone with a moderate to high susceptibility to landslides, what features in the area do you think are responsible for the incidence or susceptibility rating?  If it is zone with a low incidence or low susceptibility of landslides, what features or lack of features are responsible for the incidence or susceptibility rating?



  1. Since you decided not to take the job in Tacoma and accept the house in Orting, Washington, you are back in your house near San Francisco and comfortably settled into your job as an executive with Denyallclaims Insurance Company.  One of your friends is a developer who is planning a resort hotel project in southern California and wants to get a good deal on insurance coverage from Denyallclaims.  His project is located just to the northwest of a town called La Conchita, on the coast in Ventura County, California.  Before agreeing to insure this project, you vaguely recall having heard something about La Conchita in the news within the last couple of years.  Because you know that your company will probably take away your job (and house) if they have to pay large claims, you decide to fly down to La Conchita to check it out.  But, since your company does not like to pay travel expenses either, you decide that a better approach would be to use the internet (particularly a U.S. Geological Survey site) to check out this property. By doing so, you quickly learn that there have been two events in the last 12 years that have affected the community.
    1. Describe the geological setting of La Conchita  


    1. Discuss any disastrous events that have occurred in La Conchita within the last 12 years, including a description of events, any damage that has occurred, and any serious injuries or deaths that have resulted from these events. Be pretty detailed! This is one of the pictures of this site.




    1. Where any mitagation measures taken between the two events to prevent further disasters?  If so, what measures were taken and how effective were they?


    1. You should be able to find plenty of photos of the area that includes the area just to the northwest of La Conchita.  From those photos, what is your evaluation of the risk involved in building a resort hotel just to the northwest of La Conchita? 




  1. Whether or not you currently live in an area prone to landslides, you may in the future.  It would be a good idea to know something about some of the features to look for that might indicate a landslide may occur in the near future, especially if there is any sloping ground around the area.  Find an internet site (hint, the U.S. Geological Survey has a good one) that tells you what features to look for.
    1. Give at least 10 such features that might be noticed before landslides occur.






    1. List 4 things you should do if you suspect immediate landslide danger










  • For each of the following drawings, determine (i) What potential mass-wasting hazards exist, (ii) why these hazards exist, and (iii) what might be done to mitigate the hazard or remove the danger. Be sure to consider all information available, such as direction of fractures, type of rock or soil, slope angle, and any other features shown on the drawings.






b.      SeaCliff.GIF (11925 bytes)


c.       Creep.GIF (13440 bytes)



d.      scarps.GIF (16143 bytes)

For this one also state which site (X, Y, or Z) would be the best site on which to build your house.