The ocean monuments from the Release 1.8 Minecraft update introduce 4 new blocks (prismarine, prismarine bricks, dark prismarine, and sea lantern), 2 new mobs (guardians and elder guardians), and 2 new items (prismarine shards, prismarine crystals). You can use these items to craft 3 of the 4 new blocks.
What is a natural levee and how is it made? -Natural Levees are formed by the river in its process of flooding -A natural levee is formed by a deposit of sand or mud built up along, and sloping away from, either side of the flood plain of a river or stream.
Constructing levees along the river cuts off sediment supply causing the land to subside below sea level. Ex. New Orleans has subsided below sea level (and sea level has risen) due to the lack of natural sediment (land between Lake Pontchartrain and the Mississippi River) Distributary smaller channel that breaks off the main channel when it becomes choked with sediment