Where rivers and oceans collide

Fluvial sediment fills the coastal ocean, and sea level rise floods river valleys. This epic battle of terrestrial and marine processes occurs along all shorelines, and the complexities are especially well revealed in the Gulf of Papua, a foreland basin on the southern coast of New Guinea. Two hundred to four hundred million tons of sediment are supplied each year by the Fly and other rivers to a continental shelf that has been dissected by ancestors of these same rivers. The new sediment builds a large depositional feature known as a clinoform, which grows seaward and buries the record of earlier environments.