Eionet
Data Dictionary
This service is part of Reportnet
Concept: chalk in the concept vocabulary
| Concept URI | http://www.eionet.europa.eu/gemet/concept/11207 |
|---|---|
| Preferred label | chalk |
| Definition | A soft, pure, earthy, fine-textured, usually white to light gray or buff limestone of marine origin, consisting almost wholly (90-99%) of calcite, formed mainly by shallow-water accumulation of calcareous tests of floating microorganisms (chiefly foraminifers) and of comminuted remains of calcareous algae (such as cocoliths and rhabdoliths), set in a structureless matrix of very finely crystalline calcite. The rock is porous, somewhat friable, and only slightly coherent. It may include the remains of bottom-dwelling forms (e.g. ammonites, echinoderms, and pelecypods), and nodules of chert and pyrite. The best known and most widespread chalks are of Cretaceous age, such as those exposed in cliffs on both sides of the English Channel. |
| Notation | |
| Status | Valid |
| Status Modified | 2013-12-05 |
| Accepted Date | 2013-12-05 |
| Not Accepted Date | |
| Alternative label | |
| Has broader | |
| Is related to | |
| Has close match | |
| Source |
European Environment Agency
Kgs. Nytorv 6, DK-1050 Copenhagen K, Denmark