Fluvial dynamics and neotectonics in the Oise Valley, Paris Basin, France

To show the impact of neotectonics on fluvial morphodynamics, the author presents a geomorphological study of the Oise valley where it crosses the Pays de Bray anticline, and of the gullies and the dry valleys of the Pays de Thelle. The analysis of alluvial and colluvial forms and formations makes it possible to reconstruct the longitudinal profiles of successive river beds, from the valley heads to the Oise valley and thus to reveal anomalies. Tectonics control fluvial dynamics, but impacts are only observed if the climatic conditions are favourable: hence it can be deduced that the gullies were formed during the wet Subboreal period.