Sedimentary Evolution of the Fan Systems of the Northern Mediterranean Margin (Gulf of Lions and Western Provence) Since the Pliocene

L. Droz, G. Bellaiche, V. Coutellier

The continental rise of the northern Mediterranean margin is dominated by a coalescing fan-type sedimentation characterized by the complex stacking of interbedded sedimentary bodies, including symmetrical channel-levee complexes organized off the mouth of major canyons, curved ridges probably representing underdeveloped levees of asymmetrical systems, and widespread mass-movement deposits.

Fan-type sedimentation in the Mediterranean basin began during the Pliocene. It first appeared ubiquitous on the deep margin and related to the Messinian paleodrainage system. Later, possibly in the early Quaternary, the sedimentation became more focused and organized off major canyons of the margin. The construction of the channel-levee complexes is inferred to have been active mainly during the drops of sea level linked with the Quaternary glaciations. In contrast, mass-movement processes are thought to have been favored during the rise of sea level characterizing the interglacial periods.

On the grounds of the relative chronology of the construction of the different types of sedimentary bodies, we tentatively correlate the major active periods of the fan systems with the paleohydrographic network draining, at those times, the southern part of France. These correlations indicate that various successive regions of the Alps provided detritus to the basin through shifting feeding paths (rivers and canyons).

AAPG Search and Discovery Article #91032©1988 Mediterranean Basins Conference and Exhibition, Nice, France, 25-28 September 1988.