PROM'ONTORY, noun Latin promontorium; pro, forward, and mons, a mountain. In geography, a high point of land or rock, projecting into the sea beyond the line of the coast; a head land. It differs from a cape in denoting high land; a cape may be a similar projection of land high or low.
Schauberger
It is known that a few rivers not only transport their heavy sediment to the sea, but despite the resistance of the heavy sea-water, actually carry it far out and form promontories (haff formation). [The Energy Evolution - Harnessing Free Energy from Nature, The Transport of Ore in Double-Spiral-Flow Pipes]