Today,I read a geography magazine.I saw word “lagoon”.I am curious what lagoon is.So I search it on the internet.Here are some references.
The definition of lagoon is that a body of water separated from larger bodies of water by a natural barrier.It always separated by sandbars,barrier reefs,coral reefs,or other natural barriers.The word “lagoon” derives from the Italian word laguna,which means “pond” or “lake”
I also learned that there are two types of lagoons:atoll and coastal.Atoll lagoons form when an island completely subsides beneath the water,leaving a ring of coral that continues to grow upwards.At the center of the ring is a body of water that is often deep.The combination of coral growth and water creates a lagoon.It is said that an atoll formation may take as long as 300,000 years to occur.Here is a picture of an atoll:
Coastal lagoons form along gently sloping coasts.They are generally shallower than atoll lagoons and tend to be separated from the ocean by island ,reef,or sand bank,Most of the time,coastal lagoons are connected to the ocean by an inlet.Here is a picture of a coastal lagoon:
