Danakil Depression

The African proto-humans called Ramapithecus emerged in the Rift Valley of Africa between fourteen million and seven million years ago. This valley extends from the Danakil Depression, south of the Red Sea, well into South Africa. 

Lake Asal, southern end of the Danakil Depression Valette (1975). 

Edge of Guilietti Lake in the Danakil Depression, Ethiopia 10 samples Martini (1969). 

The Red Sea vent s metal content is similar to many other deep ocean vents, with quite high strontium values. Pushkina et al. (1982) also commented on the amounts of Ba, Cu, Fe, Mn, Ni, Pb and Zn in the brine, while Manheim (1974) in addition noted the presence of elevated amounts of As, Co, Se, U and perhaps F. Older vents in the same rift area appear to have formed Fe—Mn—Ba, Pb—Zn, and Pb—Zn—Cu— Ba deposits along the Red Sea far to the north and south of the current vents (Figs. 2.13 and 2.14). The sea floor Late Miocene shale-anhydrite breccia just south of the vents contains about 5% Zn. At the vents, the rocks contain 14—21% Fe, 0.8% Zn, 0.6-0.8% Cu and 0.5-0.7% Pb. Based upon marine sediments and the presence of several deposits of this type, it appears that the Red Sea once filled the adjacent Afar (Danakil) Depression clear to the Ethiopian Plateau (Fig. 2.13 Manheim, 1974 Bonatti et al, 1972). 

Figure 2.13 Location of the Red Sea Thermal Brines, Metal Deposit, and the Danakil Depression (Bonatti et al, 1972 reprinted with permission from Economic Geology, vol. 67 6, p. 718, Fig. 1, Bonatti, E., Fisher, D. E. Joensu, O., Rydell, H.S. and Beyth, M., 1972).

Figure 2.21 Location map of the Danakil Depression, showing Lake Giuliette, Lake Asal and the Dallol Salt Pan. (Reprinted with permission from Economic Geology, vol. 63 2, p. 125, Fig. 1, Holwerda, J. G. and Hutchinson, R. W. 1968).

Barbed, F., Borsi, S., Ferrara, G., Mannelli, G., and Varet, J. (1970). Relations Between Tectonics and Magmatology in the Northern Danakil Depression, Ethiopia. PHI. Trans. R. Soc. Land A267, 293-311. 

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