WORKING GROUP 9 
MOLLARD 
523 
the bottom of the glacial drift, these granular deposits usually contain high 
shale contents, a highly deleterious substance as far as concrete fabrication is 
concerned on the Canadian prairies. 
Associated fieldwork 
Interpretation of aerial photographs does not replace fieldwork; rather, it 
increases its effectiveness and efficiency. Airphoto and ground studies are not 
independent: instead, they are interdependent. They serve to supplement and 
to complement each other. On-the-ground checking is essential for the in 
experienced photo interpreter. The amount of fieldwork required varies not 
only with interpretive experience but also with the dictates of the study, such 
as the amount of detail required, type and quality of material required, acces 
sibility, amount of time and funds available. Certainly one of the most im 
portant functions of the photo interpreter is to economize on field sampling. 
The airphoto observer will pinpoint specific locations to check in the field. He 
will know what he should look for in the held since he will have visualized 
surface indications he feels will verify his predictions. 
References 
American Society of Photogrammetry. (1960). Manual of photographic interpretation: 
Washington, D.C., 868 p. 
Belcher, D.J. (1948a). Determination of soil conditions from aerial photographs. Photo- 
grammetric Engineering, v. 14, p. 482-488. 
Belcher, D. J. (1948b). The determination of soil conditions by aerial photographic analysis. 
2d Internat. Conf. on Soil Mechanics and Foundation Eng. Proc., v. 1, p. 313. 
Frost, R. E. (1945). Identification of granular deposits by aerial photographs. Highway 
Research Board Proc., v. 25. 
Frost, R. E. (1946). The use of aerial maps in soil studies and location of borrow pits. Kans. 
Eng. Expt. Sta. Bull. 51, p. 58. 
Hittle, J. E. (1949). Airphoto interpretation of engineering sites and materials. Photogram- 
metric Engineering, v. 15, p. 589-603. 
Jenkins, D. S., Belcher, D. J., Gregg, L. E. and Woods, K. B. (1946). The origin, distribu 
tion and airphoto identification of United States soils. U.S. Dept, of Commerce, CAAA, 
Tech. Development Rept. no. 52 and Appendix B. 
Leighty, R. D. (1957). Procedure for evaluation of fluvio-glacial terraces from airphotos 
(Abstract). Highway Research Board, v. 27, no. 5. 
Lueder, D. R. (1959). Aerial photographic interpretation. Principles and applications. 
New York, McGraw-Hill Book Co., Inc., 462. 
Mollard, J. D. (1949). Photo interpretation of transported soil materials. Engineering Inst. 
Canada Jour., Montreal, Canada, June. 
Mollard, J. D. (1952). Aerial photographic studies on the central Saskatchewan Irrigation 
Project. Cornell Univ. Ph. D. Thesis, Ithaca, N.Y., 303 p. 
Mollard, J. D. (1961). Photo interpretation shows increasing usefulness. Civil Engineering, 
October. 
Mollard, J. D. and Dishaw, H. E. (1956). How airphotos locate granular deposits. Con 
struction World, Vancouver, B.C. 
Mollard, J. D. (1958). Ten years of mapping granular deposits from aerial photographs. 
Highway Research Board Bull. 180. 
Pollock, D. H. (1955). The airphoto analysis of engineering soils. Univ. Alberta M.Sc. 
Thesis. 
Stoeckeler, E. G. and Gorrill, W. R. (1959). Airphoto analysis of terrain for highway 
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