Geography Picture Dictionary One Archipelago A large group of islands Archipelago A large group of islands Archipelago A large group of islands Atoll A ring of coral that encloses a pool of seawater Laysan Atoll A ring of coral that encloses a pool of seawater Palmyra Atoll A ring of coral that encloses a pool of seawater Badlands Wasteland that has been carved into unusual shapes by wind and water. Badlands Wasteland that has been carved into unusual shapes by wind and water. Badlands Wasteland that has been carved into unusual shapes by wind and water.