In addition, red clay deposition would be expected to clog potential 

 spawning grounds in the shelf areas of the lake. Finally, on a more quali 

 tative basis, some Lake Superior commercial fishermen claim that if the 

 clay material is readily visible in suspension during the time of freeze- 

 up, then the winter fishing catch is greatly reduced. 



This subject is a very complex one and continues to be studied in the 

 Lake Superior Basin. 



REFERENCES 



Bahnick, Donald A. Department of Chemistry, University of Wisconsin- 

 Superior, personal communication. 



Bateman, Alan M. 1950. Economic mineral deposits. 2nd Edition, John 

 Wiley and Sons, Inc. 290-294 p. 



Bayly, Brain. 1968. Introduction to petrology. Prentice Hall, Inc. 

 371 p. 



Dana, Edward S. 1954. A textbook of mineralogy. 4th Edition, 16th print- 

 ing by William E. Ford, John Wiley and Sons, Inc. 574 p. 



Dickas, A.B., J.W. Horton, R.D. Morden, P.H. Ruez and W.A. Swenson. 1973. 

 Environmental effects of harbor dredging Superior-Duluth Harbor. Cen- 

 ter for Lake Superior Environmental Studies (University of Wisconsin- 

 Superior), contract publication No. 6. 



Federal Water Pollution Control Administration, Great Lakes Basin. 1969. 

 An appraisal of water pollution in the Lake Superior Basin. 



Federal Water Pollution Control Administration, Great Lakes Region. 1970. 

 An appraisal of water pollution in the Lake Superior Basin. 



Great Lakes Basin Framework Study. 1975. Water quality (Appendix 7). 



Great Lakes Basin Commission under sponsorship of the U.S. Environmen- 

 tal Protection Agency. 



Great Lakes Basin Framework Study. 1975. Erosion and sedimentation (Ap- 

 pendix 18). Great Lakes Basin Commission under sponsorship of the 

 U.S. Environmental Protection Agency. 



Great Lakes Research Advisory Board. 1975. Asbestos in the Great Lakes 

 Basin with emphasis on Lake Superior. 35, A-6 p. 



Merliss, R.R. 1971. Talc-treated rice and Japanese stomach cancer. 

 Science, V. 173, 1141-42. 



Pontefract, R.D. and H.M. Cunningham. 1973. Penetrations of asbestoc 

 throughout the digestive tract of rats. Nature, vol. 246, 352-53. 



139 



