What an event?
An event is a natural phenomenon, acyclique, in brief in the geologic scale, spread geographically and susceptible to be protected in the sedimentary recording. Among numerous events, we hold here only those directly observable on the ground, that is:
- The marly levels of origin cinéritique or detrital,
- Hardgrounds bound to the thorough currents,
- Flints in the development or in the remarkable forms,
- The deformations and the mass reorganizations resulting from earthquakes,
- The exceptional accumulations of fossils.