ravinement
/rəˈviːnm(ə)nt/Physical Geography
noun
An irregularity or break in the layering of river or shallow marine sediments caused by interruption of deposition by erosion; a period of such erosion.
Origin
Mid 19th century (in an earlier sense). From ravine + -ment, in sense 1 perhaps after French ravinement erosion of ravines or gullies.