Crushed Gravel
Crushed gravel is obtained by crushing cobble-sized or larger portion of a gravel deposit. A gravel deposit consists of a heterogeneous mixture of rocks that often contain multiple rock types. In general, two or three rock types dominate, depending on the provenance of the source material. Thus, the characteristics of crushed gravel vary from deposit to deposit.
The properties of crushed gravel are thus depend on the source rock, and on the degree to which that rock has been weathered. The latter, in turn, depends on the processes that formed the gravel deposit. The gravel deposits can be classified into three general classes:
 | Fluvial deposits: those formed by running rivers and streams |
| Glacio-fluvial deposits formed by glacial water within or without the glacier |
| Current and ancient shoreline deposits of in lakes, seas, and oceans |
