16
1 Introducing Sea Water
(mm), the so called ¢ scale (phi scale) is used. This scale is commonly used by
geomorphologists, and it expresses size as the negative logarithm to the base
of two:
¢ = -log2 [D(mm)].
(1.8)
in which D is the particle diameter. Because the negative logarithm is used,
the coarsest particle size has the lowest ¢ value. The larger the ¢, the smaller
the particle size.