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Collecting samples from hyperacid crater lakes on the Dallol volcano



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33.87 x 25.4 cm / 300 dpi


Collecting samples from hyperacid crater lakes on the Dallol volcano in the Danakil depression in Ethiopia. The green colour of the water is due to the presence of reduced iron in solution. A multi-parameter probe is used to measure the temperature, pH, oxygen concentration, conductivity and redox potential. The samples will be analysed to find extremophile micro-organisms adapted to the conditions of the site. The aim is to study their molecular adaptation to the extreme physical-chemical parameters that characterise the local environment. In January 2016, researchers undertook a scientific expedition in this region located on the rift that traverses the Afar region and one of only two places on Earth where the oceanic crust emerges on the surface. It is a multi-extreme environment, which combines very high temperatures (up to 115 °C), very low pH (values are often negative), high saline saturation (30-50%) and the presence of toxic gas. It is a perfect site to study the limits of microbial life and could therefore provide an excellent analogy with primitive Earth environments.

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