The Seychelles microcontinent underlies the

Seychelles Seychelles (, ; ), officially the Republic of Seychelles (; Seychellois Creole: ), is an island country and archipelagic state consisting of 155 islands (as per the Constitution) in the Indian Ocean. Its capital and largest city, Victoria, ...

in the western

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

made of Late Precambrian rock. The granite outcrops of the Seychelles Islands in the central Indian Ocean were amongst the earliest examples cited by

Alfred Wegener Alfred Lothar Wegener (; ; 1 November 1880 – November 1930) was a German climatologist, geologist, geophysicist, meteorologist, and polar researcher. During his lifetime he was primarily known for his achievements in meteorology and ...

as evidence for his

continental drift Continental drift is a highly supported scientific theory, originating in the early 20th century, that Earth's continents move or drift relative to each other over geologic time. The theory of continental drift has since been validated and inc ...

theory. Ridge–plume interactions have been responsible for separating a thinned continental sliver from a large continent (i.e. India). The granites of the Seychelles Microcontinent were emplaced 750 Ma, during the late Precambrian. Thermally-induced rifting in the Somali Basin and transform rifting along the Davie Fracture Zone began in the

late Permian Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Groh ...

, 225 million years ago. The

Gondwana Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zea ...

supercontinent began to break up in the

Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...

, about 167 million years ago. At that time, East Gondwana, comprising

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

, and

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, began to separate from

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

. East Gondwana then began to separate about 115–120 million years ago when India began to move northward. The Seychelles Islands then underwent two more stages of rifting to isolate it from Madagascar and India. Between 84 and 95 million years ago, rifting separated Seychelles/India from Madagascar. An initial period of transform rifting moved the Seychelles/India block northward. Around 84 million years ago, oceanic crust started to form in the Mascarene Basin, causing a rotation of the Seychelles/India land mass. This continued until 66 million years ago when new rifting severed the Seychelles from India, forming the currently active

Carlsberg Ridge The Carlsberg Ridge is the northern section of the Central Indian Ridge, a divergent tectonic plate boundary between the African plate and the Indo-Australian plate, traversing the western regions of the Indian Ocean. The ridge of which the Carls ...

. The rift jump coincided with the maximum output of the

Deccan Traps The Deccan Traps are a large igneous province of west-central India (17–24°N, 73–74°E). They are one of the largest volcanic features on Earth, taking the form of a large shield volcano. They consist of many layers of solidified flood ...

, and volcanics found on the Seychelles Plateau have also been linked with this event. This has led to suggestions that the initiation of the Reunion plume caused rifting to jump to its current location.

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* * * * * * * * * Tectonic plates Geology of Africa Historical continents Continental fragments {{Seychelles-stub

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