Do you love the beach? Perhaps you've daydreamed from time to time about taking an extended vacation in a tropical paradise. Maybe that daydream featured you swinging in a hammock along the shore of an island. Some people even fantasize about owning a little boat they can use to hop from island to island, eating bananas fresh off the trees and soaking up the sun's rays all day long!
If this sounds like the perfect plan to you, then your dreams might one day be fulfilled by a visit to one of the world's many archipelagos. Archi…what? That's right! We said archipelagos. That's what we're talking about today in Wonderopolis.
Archipelago is a fancy geographical term for a chain or group of islands scattered across a body of water. Although archipelagos can be found in large lakes or rivers, they're most often found in the world's oceans.
Several large modern countries are actually archipelagos. Some examples of these include Indonesia, Japan, the Philippines, New Zealand, and the United Kingdom.
Many of the world's archipelagos consist of oceanic islands that were formed as a result of eruptions of volcanoes on the ocean floor. Scientists call these types of archipelagos island arcs, since several islands are often formed in a particular area known as a “hot spot."
In these areas, the Earth's crust shifted at some time in the past, but the “hot spot" of volcanic activity didn't move. As a result, volcanic eruptions formed an arc of new islands that reveals the direction the Earth's crust moved.
The Hawaiian Islands are an example of an archipelago that is also an island arc. They sit over an active “hot spot," and the Pacific tectonic plate that lies under the area continues to shift northwest. This means there will continue to be new islands added to the current chain, which now consists of over 130 islands, reefs, and atolls.
Archipelagos can be formed in other ways, too. For example, some archipelagos were formed long ago when the last ice age ended. Valleys amongst small mountain ranges along some coastlines became flooded when the ice melted, leaving a string of islands just off the coast of the mainland.
Still other archipelagos were formed as a result of a process known as post-glacial rebound. In these instances, land that was formerly crushed under the weight of massive glaciers began to expand and retake its former shape when the glaciers melted.
For example, the more than 50,000 islands in the Archipelago Sea in Finland formed this way. The process is still ongoing and new islands continue to pop up even to this day. Many of the islands in the Archipelago Sea are tiny, taking up less than an acre.
The Malay Archipelago, which sits between the Pacific and Indian Oceans off the coasts of Indonesia and Malaysia, is the world's largest archipelago. Its more than 25,000 islands used to be part of mainland Asia and appeared after glaciers disappeared after the last ice age.