Psephite
Psephite (Greek: psephos, "pebble") is either a sediment or sedimentary rock composed of fragments that are coarser than sand and which are enclosed in a matrix that varies in kind and amount. It is equivalent to a rudite. Shingle, gravel, breccia, and especially conglomerate, would all be considered psephites. It is equivalent to the Latin-derived term rudite. Psephite is more commonly used for a metamorphosed rudite.[1]
Pettijohn [2] gives the following descriptive terms based on grain size, avoiding the use of terms such as "clay" or "argillaceous" which carry an implication of chemical composition:
| Texture | Common | Greek | Latin |
|---|---|---|---|
| Coarse | gravel(ly) | psephite (psephitic) | rudite (rudaceous) |
| Medium | sand(y) | psammite (psammitic) | arenite (arenaceous) |
| Fine | clay(ey) | pelite (pelitic) | lutite (lutaceous) |
References
- ^ Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, J.A., eds. (2005) Glossary of Geology (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. ISBN 0-922152-76-4
- ^ Pettijohn F. J. (1975), Sedimentary Rocks, Harper & Row, ISBN 0-06-045191-2