Scale effects of non-uniformity on deposition from turbidity currents with reference to the Grès d'Annot of SE France

Turbidity current non-uniformity arises when flows experience changes in slope or degree of confinement. The phenomenon may operate across a range of scales with respect to flow size, to produce a range of characteristic depositional effects. Non-uniformity effects at three scales can be inferred within the Gres d'Annot exposed around the town of Annor. At the basinal scale, the very presence of sedimentary deposits may reflect a non-uniformity control. At the inferred flow scale, non-uniformity effects upon facies development can be linked to particular system geometries, for example channels or scours versus sheet systems. At the smallest scale, detailed facies heterogeneity may be linked to variability in the local sea floor topography. In poorly-exposed or subsurface systems, recognition of these effects may allow the non-uniformity regime of the parental flows to be constrained and hence permit improved prediction of the first order of sedimentary architecture away from points of control.