Guy Berthault 28 Boulevard Thiers 78250 Meulan France Contact me by email



The dating principles determined in the 17th century by an anatomy professor of Copenhagen University, Stenon (Molyavko et al., 1985), upon which the geological time-scale is founded should be re-examined and supplemented.

The most probable way of determining the genesis of sedimentary rocks is, first, to identify cycles of transgressive-regressive sequences by sequence stratigraphy. The results of our flume experiments are relevant in this connection. They show that in the presence of a current, strata in a sequence are not successive. Change of orientation in stratification, or erosion surfaces between facies of the same sequence, or between superposed sequences can result from a variation in the velocity of an uninterrupted current. Bed plane partings separating facies or sequences can result from desiccation following the withdrawal of water.

Having established the sequences of cycles, their paleohydraulic conditions must be determined. These would be minimum conditions, because it is possible that certain cycles, resulting from tectonic processes, attained an amplitude beyond anything comparable today.

Given the paleohydraulic conditions,the sediment transport capacity by unit of volume and time,can be determined in reference to sedimentary mechanics. Consequently,the time of sedimentation of a sequence is the quotient of the volume of the sequence by the sediment transport capacity. For the sequence of St.Petersburg region, this time represents only 0.05% of the time attributed by the geologic time-scale.

Knowledge of paleohydraulic conditions should help to determine better the paleo-ecological zones (depth and site) of the species which, as with the sediments, were dragged along by the currents. It might also provide a better explanation of the layering of fossil zones in the sediments of sedimentary basins.

By calling into question the principles and methods, upon which geological dates are founded, and in proposing the new approach of paleohydraulogy, I hope to open a dialogue with specialists in the disciplines concerned, who are able to appreciate the implications, and propose a geological chronology in conformity with experimental observation.