Outside glaciated areas, soil erosion from the Plio-Quaternary boundary and throughout the Quaternary has had more effect in the form of short flushes related to the onset of cooling trends than during stadials or interstadials. This results from climate instability and from vegetation destabilization. It is moreover correlated during the last 150 ka BP with reduced summer insolation rate. This explains the absence of Quaternary deposits on the almost complete Channel shelf. This approach appears valid for the Cainozoic. There is an abridged English version.