Outer Islands (Seychelles)
Encyclopedia
The Outer Islands or Coralline Seychelles is a collective term for those island
s of the Seychelles
that are not on the shallow Seychelles Bank (Seychelles Plateau) which defines the location of the Inner Islands. They are located at distances of 230 to 1150 km from the main Seychelles island of Mahé
, and are all of coral
formation. The local name for the islands is Zil Elwannyen Sesel. The islands are outside the administrative and electoral Districts of Seychelles
.
The coral islands are flat with elevated coral reefs at different stages of formation. They are generally low-lying, and often form atoll
s around a central lagoon. The soils of the corraline Seychelles are generally sandy and infertile, and hold little fresh water. The lack of natural fresh water sources and infertile soils of these islands can sustain human life only with difficulty.
The Granitic Seychelles
, by contrast, are composed of granite, and are ancient fragments of continental crust
. They are generally more mountainous and humid.
The Outer Islands are divided into five groups:
The Outer Islands comprise 211.3 km² (46% of the total land area of the Seychelles), but less than 2% of the population of the Seychelles. Eleven islands are inhabited, with the largest settlement on Coëtivy Island.
Island
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...
s of the Seychelles
Seychelles
Seychelles , officially the Republic of Seychelles , is an island country spanning an archipelago of 115 islands in the Indian Ocean, some east of mainland Africa, northeast of the island of Madagascar....
that are not on the shallow Seychelles Bank (Seychelles Plateau) which defines the location of the Inner Islands. They are located at distances of 230 to 1150 km from the main Seychelles island of Mahé
Mahé, Seychelles
Mahé is the largest island of the Seychelles, lying in the north east of the nation. The population of Mahé is 80,000. It contains the capital city of Victoria and accommodates 90% of the country's total population...
, and are all of coral
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
formation. The local name for the islands is Zil Elwannyen Sesel. The islands are outside the administrative and electoral Districts of Seychelles
Districts of Seychelles
||Seychelles is divided into 25 districts. All are located on the Inner Islands; the Outer Islands are not part of any district. Eight of the districts make up Greater Victoria, 14 are located in the rural part of the main island Mahé, two on Praslin, and one on La Digue...
.
The coral islands are flat with elevated coral reefs at different stages of formation. They are generally low-lying, and often form atoll
Atoll
An atoll is a coral island that encircles a lagoon partially or completely.- Usage :The word atoll comes from the Dhivehi word atholhu OED...
s around a central lagoon. The soils of the corraline Seychelles are generally sandy and infertile, and hold little fresh water. The lack of natural fresh water sources and infertile soils of these islands can sustain human life only with difficulty.
The Granitic Seychelles
Granitic Seychelles
The Granitic Seychelles are the islands in the Seychelles which lie in central position on the Seychelles Bank and are composed of granite rock. They make up the majority of the Inner Islands, which in addition include the coral islands along of the rim of the Seychelles Bank, namely Bird Island...
, by contrast, are composed of granite, and are ancient fragments of continental crust
Continental crust
The continental crust is the layer of igneous, sedimentary, and metamorphic rocks which form the continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called sial due to more felsic, or granitic, bulk composition, which lies in...
. They are generally more mountainous and humid.
The Outer Islands are divided into five groups:
- Southern Coral GroupSouthern Coral GroupSouthern Coral Group is a collective term for two islands of Outer Islands of the Seychelles, lying in the south of the island nation, between 135 and 300 kilometers south of the capital, Victoria, on Mahé Island.-Islands:...
(Île PlatteÎle PlatteÎle Platte, or Platte Island is 135 km south of Mahé, the main island of the Seychelles. At , it is clearly south of the Seychelles Bank and belongs to the Outer Islands...
and Coëtivy IslandCoëtivy IslandCoëtivy Island is a small coral island in the Seychelles 290 km south of Mahe, at . Along with Île Platte, the nearest neighbor 171 km northwest, it comprises the Southern Coral Group and therefore belongs to the Outer Islands . Its area is 9.31 km² and it has a population of 252. It was named...
), land area 10 km² - Amirante IslandsAmirante IslandsThe Amirante Islands , a group of coral islands and atolls, belong to the Outer Islands of the Seychelles. They stretch about 155 km from the African Banks in the north to Île Desnœufs in the south, all on the shallow Amirantes Bank , except the main island Île Desroches in...
(3 atollAtollAn atoll is a coral island that encircles a lagoon partially or completely.- Usage :The word atoll comes from the Dhivehi word atholhu OED...
s, 5 single sand cays, 3 uplifted sand cays), land area 10 km² - Alphonse GroupAlphonse GroupThe Alphonse Group belong to the Outer Islands of the Seychelles, lying in the southwest of the island nation, 403 kilometres southwest the capital, Victoria, on Mahé Island...
(Alphonse AtollAlphonse AtollAlphonse Atoll is one of two atolls of the Alphonse Group, and located 87 km south of the Amirante Islands, and just three kilometers north of St. François Atoll, the second atoll of Alphonse Group. The atoll has just one island, Alphonse Island, with a population of fewer than 300...
and St. François AtollSt. François AtollSt. François Atoll is one of two atolls of the Alphonse Group of the Seychelles, just three kilometers south of Alphonse Atoll, the second atoll of Alphonse Group. The atoll is uninhabited and has two islands, St. François and Bijoutier Island...
(Bijoutier-St. François)), land area 2 km² - Aldabra GroupAldabra GroupThe Aldabra Group are part of the Outer Islands of the Seychelles, lying in the southwest of the island nation, 1000 kilometres from the capital, Victoria, on Mahé Island.The total land area of the Aldabra Group is 175.91 km²....
(Aldabra Atoll, Assumption IslandAssumption IslandAssumption Island is a small island located at in the Indian Ocean north of Madagascar and is part of the country of the Seychelles. It is located about 30 km southeast of the Aldabra Atoll and is part of the Aldabra Group. It is a single coral island which measures 11.07 km² in area and...
, Cosmoledo AtollCosmoledoCosmoledo is an atoll of the Aldabra Group and belongs to the Outer Islands of the Seychelles. The atoll is 14.5 km long east-west, and 11.5 km north-south. The total land area is about 5.2 km², while the lagoon measures 145 km² in area . It is located at . The closest island is Astove Island,...
, Astove IslandAstove IslandAstove Island is part of the Aldabra Group of the Seychelles. It is 38 km SSE of Cosmoledo Atoll, located at . It is a raised coral island of most peculiar form: a single stretch of land, more than 1 km at the widest, almost entirely encloses a shallow lagoon...
), land area 176 km² - Farquhar GroupFarquhar GroupThe Farquhar Group belong to the Outer Islands of the Seychelles, lying in the southwest of the island nation, more than 700 kilometres southwest the capital, Victoria, on Mahé Island. The total land area of all islands in the group is less than 11 km², but the total area of the atolls measures...
(Farquhar AtollFarquhar AtollThe Farquhar Atoll is part of the Farquhar Group of islands in the Seychelles that are part of the Outer Islands. From 1965 to the independence of the Seychelles in 1976, they were a part of the British Indian Ocean Territory. The atoll is located at . The total area of the atoll, including the...
, Providence AtollProvidence AtollThe Providence Atoll is part of the Seychelles, in the Farquhar Group. The islands in the group are small, coraline and inhospitable. The atoll has a more than 30 km long north-south axis, and is up to 10 km wide. The total area covered by the atoll is approximating 200 km². The aggregate land...
(Providence-Cerf), St. Pierre IslandSt. Pierre IslandSt Pierre Island is a raised reef island west of Providence Atoll and part of Farquhar Group, which belongs to the Outer Islands of the Seychelles. The island is located 35 km west of Cerf Island of Providence Atoll, 704 km from Mahé and 500 km ENE of Aldabra...
), land area 11 km²
The Outer Islands comprise 211.3 km² (46% of the total land area of the Seychelles), but less than 2% of the population of the Seychelles. Eleven islands are inhabited, with the largest settlement on Coëtivy Island.