geo.wikisort.org - Mountains

Darfur Dome or Darfur Volcanic Province is an area of about 100x400 km in Western Sudan. As well as its best-known and central feature, Deriba Crater, it encompasses the surrounding Marra Mountains (Jebel Marra) and Tagabo Hills, both formed around 16–10 Ma., and the Meidob Hills, formed around 6.8 Ma.[1]

There are currently two competing theories concerning Darfur Dome’s formation. The conventional view is that magmatism is the product of a rising mantle plume, with active volcanism being triggered by stress resolution along the Central African Fault Zone.[1][2] Evidence for a plume origin includes domal uplift, gravity anomalies, and low seismic velocity zones in the mantle,[1][2][3][4][5][6] though there is disagreement over whether these indicate a discreet, narrow plume under the Darfur region[1][2][3] or a broad superplume with conduits feeding several African hotspots.[4][5][6]

Recently, some scientists have argued for a tectonic origin in which lithospheric extension, asthenospheric shear, and small-scale convection have enabled passive melting of shallow source material.[7][8][9][10] This interpretation is supported by high seismic shear wave velocities which indicate shallow, cold downwellings[7] as well as normal heat-flow and low helium isotope ratios.[8][9]

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  Deriba Caldera
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  Jebel Marra Deriba Lakes
• 
  Central Africa showing CASZ.

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