@misc{10481/59480,
year = {2019},
url = {http://hdl.handle.net/10481/59480},
abstract = {One of the latest volcanic features of the Erta Ale range
at the Afar Triangle (NE Ethiopia) has created a polyextreme
hydrothermal system located at the Danakil depression on top of a
protovolcano known as the dome of Dallol. The interaction of the
underlying basaltic magma with the evaporitic salts of the Danakil
depression has generated a unique, high-temperature (108 °C),
hypersaline (NaCl supersaturated), hyperacidic (pH values from 0.1
to −1.7), oxygen-free hydrothermal site containing up to 150 g/L of
iron. We find that the colorful brine pools and mineral patterns of
Dallol derive from the slow oxygen diffusion and progressive oxidation
of the dissolved ferrous iron, the iron-chlorine/-sulfate complexation,
and the evaporation. These inorganic processes induce the
precipitation of nanoscale jarosite-group minerals and iron(III)-
oxyhydroxides over a vast deposition of halite displaying complex
architectures. Our results suggest that life, if present under such conditions, does not play a dominant role in the geochemical
cycling and mineral precipitation at Dallol as opposed to other hydrothermal sites. Dallol, a hydrothermal system controlled by
iron, is a present-day laboratory for studying the precipitation and progressive oxidation of iron minerals, relevant for
geochemical processes occurring at early Earth and Martian environments},
organization = {This work received
funding from the European Research Council under the
Programme (FP7/2007-2013)/ERC Grant Agreement 340863
(Prometheus) and from MINECO, ref CGL2016-78971-P,
AEI/FEDER, UE”.},
publisher = {American Chemical Society},
keywords = {Iron oxidation},
keywords = {Hyperacidic},
keywords = {Hydrothermal},
keywords = {Polyextreme},
title = {A Polyextreme Hydrothermal System Controlled by Iron: The Case of Dallol at the Afar Triangle},
doi = {10.1021/acsearthspacechem.8b00141},
author = {Kotopoulou, Electra and Delgado Huertas, Antonio and García Ruiz, Juan Manuel and Domínguez Vera, José Manuel and López García, José María and Guerra Tschuschke, Isabel},
}