Geology of the Southern Red Sea and Gulf of Aden
The Red Sea and the Gulf of Aden were formed as the Arabian plate separated
from Nubia, as Nubia obliquely collided with the Eurasian plate (Figure
6). NE-directed extension between 35-27million years ago lead to the continents
rifting apart and the formation of new oceans along the line of the Red
Sea and Gulf of Aden. At the same time as this, between about 31-29Ma,
there was a massive eruption of lava - flood basalts - covering some 600,000km2
of the region. Along the margins of the Red Sea these lavas are up to
2000m thick. Sea floor spreading in the Gulf
of Aden begun about 16Ma and about 4Ma in the Red Sea.
With
the East African Rift System, the Red Sea and the Gulf of Aden form the
Afar triple junction. The Red Sea runs roughly straight for 2000km northwards
to where it joins the Aqaba-Dead Sea transform rift system (where the
plates are sliding past each other). The Gulf of Aden is straight near
the triple junction, before curving round to link in the with mid-ocean
ridge system in the Indian Ocean (Figure 7).
Across both the Gulf of Aden mid-ocean ridge system and the southernmost
part of the Red Sea the plates are moving not only apart but also sliding
past each other with one side moving to the left with respect to the other.
For references used, please see technical version.
Structural Geology of the
Afar Region
The Afar Depression
Ethiopian and Somalian plateaux
Danakil and Ali-Sabieh Blocks
Main Ethiopian Rift (MER)
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