TheSeychelles microcontinent underlies theSeychelles in the westernIndian Ocean made of Late Precambrian rock.
The granite outcrops of theSeychelles Islands in the central Indian Ocean were amongst the earliest examples cited byAlfred Wegener as evidence for hiscontinental drift theory.[1] Ridge–plume interactions have been responsible for separating a thinned continental sliver from a large continent (i.e. India).[2]
The granites of the Seychelles Microcontinent were emplaced 750Ma, during the late Precambrian.[3][4][5][6] Thermally-induced rifting in theSomali Basin and transform rifting along theDavie Fracture Zone began in thelate Permian, 225 million years ago. TheGondwana supercontinent began to break up in theMiddle Jurassic, about 167 million years ago. At that time, East Gondwana, comprisingAntarctica,Madagascar,India, andAustralia, began to separate fromAfrica. East Gondwana then began to separate about 115–120 million years ago when India began to move northward.[5]
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.[5] Around 84 million years ago, oceanic crust started to form in theMascarene Basin,[7] 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 activeCarlsberg Ridge. The rift jump coincided with the maximum output of theDeccan Traps,[8] and volcanics found on the Seychelles Plateau have also been linked with this event.[5] This has led to suggestions that the initiation of theReunion plume caused rifting to jump to its current location.[9]
{{cite book}}:ISBN / Date incompatibility (help) | ThisSeychelles-related article is astub. You can help Wikipedia byadding missing information. |
