Blue Nile rift
Encyclopedia
The Blue Nile rift is a major geological formation in the Sudan
, a rift
with a NW trend that terminates on the Central African Shear Zone
.
It was formed through crustal extension during the break-up of Gondwana
.
The rift, and other rifts in the area such as the Bahr El Arab rift
and White Nile rift
, appears to have been activated several times since the Paleozoic
era, which ended about 250 Ma.Ma = Million years ago
During periods of rapid uplift and subsidence, the rifts accumulated sediments of different ages, origins and methods of deposition.
Late Jurassic
rifting occurred in the Blue Nile rift, with east-west extension in half-graben
connected by large-scale shear zones and pull-apart basins, and early Cretaceous
rifting re-activated the Jurassic basin.
The Blue Nile Basin
in Ethiopia
may be a southeastern extension of the rift.
Further to the southeast, the late Palaeozoic-Mesozoic Ogaden Rift
is aligned with the Blue nile rift.
Sudan
Sudan , officially the Republic of the Sudan , is a country in North Africa, sometimes considered part of the Middle East politically. It is bordered by Egypt to the north, the Red Sea to the northeast, Eritrea and Ethiopia to the east, South Sudan to the south, the Central African Republic to the...
, a rift
Rift
In geology, a rift or chasm is a place where the Earth's crust and lithosphere are being pulled apart and is an example of extensional tectonics....
with a NW trend that terminates on the Central African Shear Zone
Central African Shear Zone
The Central African Shear Zone is a wrench fault system extending in an ENE direction from the Gulf of Guinea through Cameroon into Sudan.The structure is not well understood....
.
It was formed through crustal extension during the break-up of Gondwana
Gondwana
In paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...
.
The rift, and other rifts in the area such as the Bahr El Arab rift
Bahr el Arab rift
The Bahr el Arab rift is a major geological feature in the southwest Sudan.The Bahr el Arab rift is made up of the Baggara graben, between the Central African Republic and the Nuba Mountains to the east, and the Sudd graben further south...
and White Nile rift
White Nile rift
The White Nile rift is one of several rifts in central Sudan running in a NW direction and terminating in the Central African Shear Zone.The rift is a Cretaceous/Tertiary structure that has similar tectonic characteristics to the Southern Sudan Rift, Blue Nile rift and Atbara rift.These rifts...
, appears to have been activated several times since the Paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...
era, which ended about 250 Ma.Ma = Million years ago
During periods of rapid uplift and subsidence, the rifts accumulated sediments of different ages, origins and methods of deposition.
Late Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
rifting occurred in the Blue Nile rift, with east-west extension in half-graben
Graben
In geology, a graben is a depressed block of land bordered by parallel faults. Graben is German for ditch. Graben is used for both the singular and plural....
connected by large-scale shear zones and pull-apart basins, and early Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
rifting re-activated the Jurassic basin.
The Blue Nile Basin
Blue Nile Basin
The Blue Nile Basin is a major geological formation in the northwestern Ethiopian Plateau formed in the Mesozoic Era during a period of crustal extension associated with the break-up of Gondwana, and filled with sedimentary deposits...
in Ethiopia
Ethiopia
Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...
may be a southeastern extension of the rift.
Further to the southeast, the late Palaeozoic-Mesozoic Ogaden Rift
Ogaden Basin
The Ogaden Basin is an area of Ogadkenya that may hold significant reserves of crude oil and natural gas. The basin covers an area of some 350,000 squarekilometres and is formed from sedimentary rocks up to 10,000 meters thick...
is aligned with the Blue nile rift.