CS 128/ES 228 - Lecture 13a1 Spatial Analysis – A Case Study

CS 128/ES 228 - Lecture 13a 1

Spatial Analysis – A Case Study


Problem Landslides are present in certain

areas of West Virginia

Question: How much of a determinant is land slope in this matter?


Where to begin? West Virginia

Landslide and Slide Prone Areas map

Paper only so scanned in


What to add?

DEMs available at different resolutions

10 meter and 30 meter resolution DEMs imported

Also a Geology map and a DOQQ


Adding relevant data Landslide

polygons added through “heads up” digitization

Attribute table used for determining area of slides


Hypothesis

Slope has something to do with the prevelance of landslides

Literature suggests that 35 degrees is a critical value


Getting Slope Information ArcMap’s Spatial Analysis was

applied to DEMs

Slope shown by color – degree values in Table of Contents


30 meter resolution


10 meter resolution


More interesting analysis Intersecting slope map with slide

polygons layer allows us to determine average slope of a slide

Determined to be 34.81 degrees


Further filtering – 10 m


Further filtering – 30 m


Final product

What layers should be included?

How should they be arranged?


A Useful Map?


Intriguing Questions

Why doesn’t 30 m map do “better”?

What role does geology play? What about soil type?


BIBLIOGRAPHY All figures (and details about the

study) were taken from:

http://www.nrac.wvu.edu/rm493-591/fall2001/students/kish/The%20Use%20of%2010%20Meter%20and%2030%20Meter%20Digital%20Elevation%20Models%20for%20Determining%20Areas%20Susceptible%20to%20Landsliding%20in%20the%20Morgantown%20N.htm

Better approach – go to http://www.nrac.wvu.edu/rm493-591/ and explore projects (This one from Fall 2001 – Patrick Kish)

Documents

CS 128/ES 228 - Lecture 13a1 Spatial Analysis – A Case Study