GEOLOGY & PLANETARY SCIENCE A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site gravel A collection of rock particles whose diameter ranges from 2mm to 4mm. In general terms, gravel particles may be as large as pebbles. Gravel is used commercially in the making in the concrete. See conglomerate and sand. Related category    • GEOLOGY AND PLANETARY SCIENCE Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History BACK TO TOP