progradation

[ proh-grey-dey-shuh n ]
/ ˌproʊ greɪˈdeɪ ʃən /

noun Geology.

seaward growth of a beach, delta, fan, etc., by progressive deposition of sediment by rivers or shoreline processes.

Origin of progradation

1905–10; prograde ( pro-1 + (retro)grade) + -ation