The Darfur Volcanic Province from
ISS . 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]
Deriba Caldera
Central Africa showing
CASZ .
Notes
^
a
b
c
d Franz, G.; Pudlo, D.; Urlacher, G; Haussmann, U; Broven, A.; Wemmer, K. (1994).
"The Darfur Dome, western Sudan: the product of a subcontinental mantle plume" . Geologische Rundschau . 83 (3): 614–623.
Bibcode :
1994GeoRu..83..614F .
doi :
10.1007/BF01083232 .
S2CID
198144219 .
^
a
b
c Franz, G.; Steiner, G.; Volker, F.; Pudlo, D.; Hammerschmidt, K. (1999).
"Plume related alkaline magmatism in central Africa—the Meidob Hills (W Sudan)" . Chemical Geology . 157 (1–2): 27–47.
Bibcode :
1999ChGeo.157...27F .
doi :
10.1016/S0009-2541(98)00195-8 .
^
a
b Burke, K. (1996).
"The African plate" . South African Journal of Geology . 99 (4): 339–410.
^
a
b Ebinger, C.J.; Sleep, N.H. (1998).
"Cenozoic magmatism throughout east Africa resulting from impact of a single plume" . Nature . 395 (6704): 788–791.
Bibcode :
1998Natur.395..788E .
doi :
10.1038/27417 .
S2CID
4379613 .
^
a
b Zhao, D (2007).
"Seismic images under 60 hotspots: Search for mantle plumes" . Gondwana Research . 12 (4): 335–355.
Bibcode :
2007GondR..12..335Z .
doi :
10.1016/j.gr.2007.03.001 .
^
a
b Steinberger, B. (2000).
"Plumes in a convecting mantle: Models and observations for individual hotspots" . Journal of Geophysical Research . 105 (B5): 11127–11152.
Bibcode :
2000JGR...10511127S .
doi :
10.1029/1999JB900398 .
^
a
b King, S.D.; Ritsema, J. (2000).
"African hot spot volcanism: Small-scale convection in the upper mantle beneath cratons" . Science . 290 (5494): 1137–1140.
Bibcode :
2000Sci...290.1137K .
doi :
10.1126/science.290.5494.1137 .
PMID
11073447 .
^
a
b Sebai, A.; Stutzmann, E.; Montagner, J-P.; Sicilia, D.; Beucler, E. (2006).
"Anisotropic structure of the African upper mantle from Rayleigh and Love wave tomography" . Physics of the Earth and Planetary Interiors . 155 (1–2): 48–62.
Bibcode :
2006PEPI..155...48S .
doi :
10.1016/j.pepi.2005.09.009 .
^
a
b Montagner, J-P.; Marty, B.; Stutzmann, E.; Sicilia, D.; Cara, M.; Pik, R.; Lévêque, J-J.; Roult, G.; Beucler, E.; Debayle, E. (2007).
"Mantle upwellings and convective instabilities revealed by seismic tomography and helium isotope geochemistry beneath eastern Africa" . Geophysical Research Letters . 34 (21).
Bibcode :
2007GeoRL..3421303M .
doi :
10.1029/2007GL031098 .
^ Sicilia, D.; Montagner, J-P.; Cara, M.; Stutzmann, E.; Debayle, E.; Lépinea, J-C.; Lévêque, J-J.; Beucler, E.; Sebai, A.; Roult, G.; Ayele, A.; Sholan, J.M. (2008).
"Upper mantle structure of shear-waves velocities and stratification of anisotropy in the Afar Hotspot region" . Tectonophysics . 462 (1–4): 164–177.
Bibcode :
2008Tectp.462..164S .
doi :
10.1016/j.tecto.2008.02.016 .
13°5′0″N 24°20′0″E / 13.08333°N 24.33333°E / 13.08333; 24.33333