Table C-5. Phi-millimeter conversion table 



Table C-5 is reproduced from the Journal of Sedimentary Petrotogut with 

 the permission of the author and publisher. It was taken from the Harry G. 

 Page, "Phi-Millimeter Conversion Table," published in Volume 25, pp. 285-292, 

 1955, and includes that part of the table from -5.99 (about 63 mm) to +5.99 

 (about 0.016 mm) which provides a sufficient range for beach sediments. The 

 complete table extends from about -6.65 (about 100 mm) to +10.00 (about 0.001 

 mm) . 



The first column of the table shows the absolute value of phi. If it is 

 positive, the corresponding diameter value is shown in the second column. If 

 phi is negative, the corresponding diameter is shown in the third column of 

 the table. In converting diameter values in millimeters to their phi 

 equivalents, the closest phi value to the given diameter may be selected. It 

 is seldom necessary to express phi to more than two decimal places. 



The conversion table is technically a table of negative logarithms to the 

 base 2, from the defining equation of phi: ^ = log„d , where d is the 

 diameter in millimeters 



Values of phi can also be determined with an electronic calculator having 

 scientific notation by use of of the following relationship: 



<|) = -log d = - 



lOg^gd 



2" , 2 

 l°SlO 



The table begins on the following page. 



C-38 



