GEO 4120c/5028c Workshop 8
Aerial Photo Interpretation 1: Landforms, Drainage Patterns, Geology, Soils

 6 April 2009

Introduction

Interpretation of aerial photography is a major method for landform identification. Landforms are, according to Doug Way (Way, D. 1973. Terrain Analysis: A Guide to Site Selection Using Aerial Photographic Interpretation. Dowden, Hutchinson and Ross, Stroudsburg, PA):

"Terrain features formed by natural processes, which have definable composition and range of physical and visual characteristics that occur wherever the landform is found."

Thus, air photo interpretation becomes a way of determining geological, soils, and hydrological characteristics as they are linked to landforms.

Sources of imagery in this exercise: Wanless, H.R.  Aerial Stereograms. Hubbard Scientific Press. 92 pages.

Exercise

1. From all the stereograms in Wanless, select five with landforms that you have never knowingly seen and five with landforms that you know well. Restrict the following tasks to no more than one page per landform, and preferably a lot less.

a. List the plate number and title of the stereogram, and name the landform that you studied.

             b. Describe the morphology of each landform - what is their shape, smoothness, texture, drainage patterns, land-use patterns, orientation, and any other useful descriptor. Use your own words, not the caption's.

             c. Describe the vegetation patterns associated with each landform, and what causes the vegetation patterns - what is the mechanism for the pattern (e.g. distribution of soil moisture, soil parent material, etc.). Use your own words, not the caption.

             d. Describe the climate of the area in the stereogram (use your own words and not the narrative in the caption) that gives you the clues as to climate. These clues will be detected from the vegetation, the patterns of erosion and deposition, etc.

          2. Calculate the drainage density of three of the following stereograms: plate 7, 26, 43, 69, or 70. Your are given the scale and have the measurement tools so this should be easy by now. Ho do the densities compare with each other? Why?

          3. Interpret the vegetation and land-use patterns in three of the following stereograms: plate 26, 31, 32, 45, 59, 71, 73, 74, 84, or 85. To interpret is to describe the pattern, then describe the underlying geological, soils, and hydrological factors that cause the patterns. Again, go beyond the narrative in the captions and use your knowledge and powers of deduction to interpret the images. Again, use your own words, be comprehensive but concise, and use a little imagination.

Turn in the written report to G:\share\GIS 4120c Aerial Photo Interpretation\yourfolder (Be sure to name the report with your name in addition to "workshop_8"), and send me an e-mail that you have done so, or turn in a printed copy at the beginning of the next class.