An archipelago ( ), sometimes called an island group or island chain, is a chain, cluster, or collection of islands, or sometimes a sea containing a small number of scattered islands. Examples of archipelagos include: the Indonesian Archipelago, the Andaman and Nicobar Islands, the Lakshadweep Islands, the Galápagos Islands, the

Japanese archipelago The Japanese archipelago (Japanese: 日本列島, ''Nihon rettō'') is a group of 6,852 islands that form the country of Japan, as well as the Russian island of Sakhalin. It extends over from the Sea of Okhotsk in the northeast to the East Chin ...

, the Philippine Archipelago, the Maldives, the Balearic Islands, The Bahamas, the Aegean Islands, the Hawaiian Islands, the Canary Islands, Malta, the Azores, the

Canadian Arctic Archipelago The Arctic Archipelago, also known as the Canadian Arctic Archipelago, is an archipelago lying to the north of the Canadian continental mainland, excluding Greenland (an autonomous territory of Denmark). Situated in the northern extremity of ...

, the British Isles, the islands of the Archipelago Sea, and Shetland. They are sometimes defined by political boundaries. For example, the Gulf archipelago off the northeastern Pacific coast forms part of a larger archipelago that geographically includes Washington state's San Juan Islands; while the Gulf archipelago and San Juan Islands are geographically related, they are not technically included in the same archipelago due to manmade geopolitical borders.

Etymology

The word ''archipelago'' is derived from the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

ἄρχι-(''arkhi-'', "chief") and πέλαγος (''pélagos'', "sea") through the Italian ''arcipelago''. In antiquity, "Archipelago" (from Medieval Greek *ἀρχιπέλαγος and

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

) was the proper name for the Aegean Sea. Later, usage shifted to refer to the Aegean Islands (since the sea has a large number of islands).

Geographic types

Archipelagos may be found isolated in large amounts of water or neighbouring a large land mass. For example,

Scotland Scotland (, ) is a Countries of the United Kingdom, country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a Anglo-Scottish border, border with England to the southeast ...

has more than 700 islands surrounding its mainland, which form an archipelago. Archipelagos are often volcanic, forming along

island arc Island arcs are long chains of active volcanoes with intense seismic activity found along convergent tectonic plate boundaries. Most island arcs originate on oceanic crust and have resulted from the descent of the lithosphere into the mantle alon ...

s generated by subduction zones or hotspots, but may also be the result of

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is dis ...

, deposition, and

land elevation Post-glacial rebound (also called isostatic rebound or crustal rebound) is the rise of land masses after the removal of the huge weight of ice sheets during the last glacial period, which had caused isostatic depression. Post-glacial rebound a ...

. Depending on their geological origin, islands forming archipelagos can be referred to as ''oceanic islands'', ''continental fragments'', and ''continental islands''.

Oceanic islands

Oceanic islands are mainly of volcanic origin, and widely separated from any adjacent continent. The Hawaiian Islands and Galapagos Islands in the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

, and Mascarene Islands in the south

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by t ...

are examples.

Continental fragments

Continental fragments correspond to land masses that have separated from a continental mass due to tectonic displacement. The Farallon Islands off the coast of

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

are an example.

Continental archipelagos

Sets of islands formed close to the coast of a continent are considered continental archipelagos when they form part of the same continental shelf, when those islands are above-water extensions of the shelf. The islands of the

Inside Passage The Inside Passage (french: Passage Intérieur) is a coastal route for ships and boats along a network of passages which weave through the islands on the Pacific Northwest coast of the North American Fjordland. The route extends from southeaste ...

off the coast of

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

and the

are examples.

Artificial archipelagos

Artificial archipelagos have been created in various countries for different purposes.

Palm Islands The Palm Islands are three artificial islands, Palm Jumeirah, Deira Island and Palm Jebel Ali, on the coast of Dubai, United Arab Emirates. The Palm Islands were conceived around the same time as The World, another artificial island project i ...

and

The World Islands The World Islands (Arabic: جزر العالم; ''Juzur al-Ālam'') are an archipelago of small artificial islands constructed in the shape of a world map, located in the waters of the Persian Gulf, off the coast of Dubai, United Arab Emirate ...

off Dubai were or are being created for leisure and tourism purposes.

Marker Wadden The Marker Wadden is an artificial archipelago under development in the Markermeer, a lake in the Netherlands. The first island was inaugurated on 24 September 2016. Project The project was proposed in 2012 by the Vereniging Natuurmonumente ...

in the Netherlands is being built as a conservation area for birds and other wildlife.

Further examples

The largest archipelagic state in the world by area, and by population, is Indonesia.

References

External links

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30 Most Incredible Island Archipelagos
{{Authority control Coastal and oceanic landforms Oceanographical terminology