<Ul> <Li> Littoral zone </Li> <Li> Intertidal zone </Li> <Li> Estuaries </Li> <Li> Kelp forests </Li> <Li> Coral reefs </Li> <Li> Ocean banks </Li> <Li> Continental shelf </Li> <Li> Neritic zone </Li> <Li> Straits </Li> <Li> Pelagic zone </Li> <Li> Oceanic zone </Li> <Li> Seamounts </Li> <Li> Hydrothermal vents </Li> <Li> Cold seeps </Li> <Li> Demersal zone </Li> <Li> Benthic zone </Li> </Ul> <Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The continental shelf is an underwater landmass which extends from a continent, resulting in an area of relatively shallow water known as a shelf sea . Much of the shelves were exposed during glacial periods and interglacial periods . </P>

A large flat area on the ocean floor is called