PREFACE 



This technical aid provides an analysis of the phi grade scale used 

 in describing sediment texture. The work was carried out under the sedi- 

 ment hydraulic interaction program of the U.S. Army Coastal Engineering 

 Research Center (CERC) . 



The report was prepared by Dr. R.D. Hobson of the Engineering 

 Geology Branch, Engineering Development Division, CERC. 



Comments on this publication are invited. 



Approved for publication in accordance with Public Law 166, 79th 

 Congress, approved 31 July 1945, as supplemented by Public Law 172, 88th 

 Congress, approved 7 November 1963. 



TED E. BISHOP 



Colonel, Corps oT Engineers 



Commander and Director 



