Why The Danakil Depression In Ethiopia Glows With Unearthly Mineral Pigments | Femina.in

Sited in northern Ethiopia’s Afar region, the Danakil Depression looks less like a corner of Africa and more like another planet. It sits over 100 metres below sea level, and is one of the hottest and lowest places on Earth. Its Dallol hydrothermal field is ablaze with acid-green pools, sulphur-yellow crusts, rust-orange terraces, and blinding white salt – which come from heat, brine, and metals rising from deep within the Earth. Indeed, the Danakil Depression is a rare, fast-changing window into the restless interior of our planet, and an opportunity to study how Earth works.

1. A Continental Tearing

The Danakil Depression sits at a triple junction – a place where the Nubian, Somali and Arabian plates are slowly pulling apart. At this point, the crust stretches and thins, causing the land to sink into a deep basin, which is the reason why parts of it lie well below sea level. The thinness of the crust lets magma rise close to the surface, inflaming volcanoes such as Erta Ale, with its persistent lava lake. Incidentally, this is the same rifting that might one day split East Africa and let the ocean in. The depression is, in fact, a young ocean basin in the making.

2. Vast Salt Deposit

The Red Sea repeatedly flooded this basin millions of years ago, but the water evaporated under the intense heat, leaving behind salt layers, some of them over a kilometre thick. These salt deposits are the landscape’s raw material. The salt is dissolved by groundwater into dense brines, and rising pressure pushes them back to the surface. There, they crystallise into white domes, terraces, and ridges. Afar caravans have cut salt blocks from this plain down the centuries and carried them to highland markets by camel.

3. Hydrothermal Heat And Acid

The groundwater is heated by magma beneath the rift. It then circulates through the salt and volcanic rock. Extremely salt and acidic, this hot fluid has pH values near or below zero. Climbing through cracks, it leaches iron, sulphur and other elements from the rock, bubbling up into vivid springs and pools at the surface at Dallol, a low volcanic dome. This is a dynamic, constantly-changing system – channels shift, pools dry out, and new vents open within days or weeks.

4. Mineral Chemistry and Colour

The hues of the Danakil Depression come from specific chemistry. The distinctive bright yellow crusts are formed by sulphur, while oxidised iron colours terraces red, orange, and brown. The pools get their eerie green from dissolved ferrous iron and chloride compounds. The white and cream come from pure salt. The colours also change with evaporation, temperature shifts, and the reaction of iron with air. The extreme desert sun and constant fluid flow makes it seem as if the landscape is being constantly repainted. 

Frequently-Asked Questions (FAQs) About The Danakil Depression

Q. Where is the Danakil Depression?

Q. What is the depth of the Danakil Depression?

A. Parts of the Danakil Depression lie roughly 100 to 125 metres below sea level.

Q. What causes the bright colours?

Q. Is the water in the Danakil Depression safe to touch?

Q. Can tourists visit the Danakil Depression?

A. Yes, but check current travel advice as conditions can change with regard to regional security. Visits are possible only with armed escorts and guided tours.