Wentworth classification

Wentworth classification

[′went‚wərth ‚klas·ə·fə′kā·shən]
(geology)
A logarithmic grade for size classification of sediment particles starting at 1 millimeter and using the ratio of 1/2 in one direction (and 2 in the other), providing diameter limits to the size classes of 1, ½, ¼, etc. and 1, 2, 4, etc.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.