# Danakil Depression (DD-055) > The Danakil Depression in Ethiopia's Afar region lies mostly about 100 m below sea level, reaching around 124 m. It has a mean annual temperature of about 35 °C. The colorful terrain in the Reel's footage is the Dallol hydrothermal field. There, hot, hyperacidic, iron-rich brines rise through a thick salt deposit, and the iron oxidizes into yellow, green and orange crusts. - Department: Nature (also Locations) - First published: 2025-05-30 - Last updated: 2025-05-30 - Permalink: https://detailenjoyer.com/case/danakil-depression/ - Author: Marcus Easterling (DetailEnjoyer), The Detail Department ## On the timeline - **about 32,000 years ago**: The most recent Red Sea incursion adds to the Danakil salts - **1926**: Phreatic eruption forms Dallol's Black Lake Full timeline: https://detailenjoyer.com/timeline/?case=danakil-depression ## Quick facts - **DD-055-F01**: Dallol's springs have measured pH values as low as about -1.7. _(Write-up · Exhibit C (Dallol's brines))_ - **DD-055-F02**: Most of the Danakil Depression lies about 100 m below sea level, reaching around 124 m. _(Write-up · Exhibit A (Below sea level))_ ## Write-up One of the hottest, driest and lowest places on Earth. Dallol's acid springs get their colors mostly from iron. 1. **Below sea level**: The Danakil Depression is a narrow lowland about 250 km long. Most of it lies about 100 m below sea level, and it reaches around 124 m below at Lake Assale and near Dallol. That makes it one of the lowest land areas in Africa and in the world. Its northern part is a salt plain of about 4,000 square km. 2. **Hot and dry**: The area has a hot desert climate. Mean annual temperature is about 35 °C, and annual rainfall is usually below 50 mm. More than 2 km of evaporite salts were laid down by repeated incursions of the Red Sea, the most recent about 32,000 years ago. 3. **Dallol's brines**: At Dallol, basaltic magma heats the buried salts. The result is a hydrothermal system with springs at up to 108 °C. They are supersaturated with salt, contain no oxygen, have pH values from about 0.1 down to -1.7, and carry up to 150 g of iron per liter. 4. **Where the colors come from**: The researchers found that the colorful pools and crusts come from slow oxidation of dissolved ferrous iron, from iron-chloride and iron-sulfate complexes, and from evaporation. Together these precipitate jarosite-group minerals and iron oxyhydroxides over salt. They conclude that life, if present, does not play a dominant role in this mineral cycling. 5. **The lava lake is elsewhere**: Dallol itself is a low dome with a summit crater about 100 m wide, last shaped by a phreatic eruption in 1926. The Depression's lava lake belongs to Erta Ale, a volcano farther south on the same rift segment that hosts a perennial lava lake. ## Related case files - [The Glacier That Bleeds (DD-725)](https://detailenjoyer.com/case/the-glacier-that-bleeds/): Another landscape colored by iron-rich brine: Blood Falls, stained red as its iron oxidizes in air. - [Dead Pools (DD-049)](https://detailenjoyer.com/case/dead-pools/): Brines so extreme they're deadly: seafloor brine pools that kill animals that fall in. - [Heavenly Lake (DD-019)](https://detailenjoyer.com/case/heavenly-lake/): The opposite extreme: Namtso, a saltwater lake 4,718 m up, while Danakil lies below sea level. - [Kawah Ijen (DD-600)](https://detailenjoyer.com/case/kawah-ijen/): Dallol, in the Danakil, also has blue sulfur fire - [Doom Plume (DD-636)](https://detailenjoyer.com/case/doom-plume/): Another volcanic landscape - [Fissure Flames (DD-645)](https://detailenjoyer.com/case/fissure-flames/): Volcanic ground where plates are pulling apart - [Rainbow Mountains (DD-646)](https://detailenjoyer.com/case/rainbow-mountains/): Another landscape colored by minerals - [Stick Walk (DD-668)](https://detailenjoyer.com/case/stick-walk/): Another case from Ethiopia - [Siwa Salt Oasis (DD-675)](https://detailenjoyer.com/case/siwa-salt-oasis/): Another salt-crusted desert depression below sea level - [Mount Bokty (DD-706)](https://detailenjoyer.com/case/mount-bokty/): Another landscape colored by iron ## Reel vs. record - **Colors**: the Reel credits 'blue or green' salts to mineral-rich brines. Studies show Dallol's colors come mainly from iron, as dissolved ferrous iron oxidizes and precipitates over salt. The Reel's own footage is mostly yellow, green and orange. - **Lava lakes**: there is no lava lake at the colorful Dallol site shown. The Depression's lava lake is at Erta Ale, farther south. - **Note**: 'Acidic' undersells it: Dallol's springs reach pH about 0.1 to -1.7 and up to 108 °C. They are also oxygen-free and carry up to 150 g/L of iron. - **Note**: 'Lowest': the Depression lies mostly about 100 m below sea level, reaching around 124 m. It is one of the lowest land areas in Africa and in the world, not the single lowest. - **Missing context**: the 'salt flats' sit on more than 2 km of evaporites left by repeated Red Sea incursions, the most recent about 32,000 years ago. ## Video: Danakil Depression: One of the Hottest, Driest and Lowest Places on Earth - Duration: 20.4 s · Published: 2025-05-30 - File: https://detailenjoyer.com/assets/videos/DKSo7DTSNp1.mp4 ### Transcript DID YOU KNOW? The Danakil Depression in Ethiopia is one of the hottest, driest, and lowest places on Earth, famous for its otherworldly landscape of acidic hot springs, salt flats, lava lakes, and colorful mineral deposits. Despite its extreme conditions, some stunning natural phenomena occur there, including salt formations that sometimes appear in shades of blue or green, due to mineral-rich brines. NOW YOU KNOW! ## Questions & answers **Q: What mainly gives Dallol's pools and crusts their colors?** A: The researchers attribute the colors to progressive oxidation of dissolved ferrous iron. _(Source: Write-up · Exhibit D (Where the colors come from) · Kotopoulou et al. (2019), A Polyextreme Hydrothermal System Controlled by Iron: The Case of Dallol at the Afar Triangle, ACS Earth and Space Chemistry (PMC))_ **Q: Roughly how acidic can Dallol's springs get?** A: Measured pH ranges from about 0.1 down to -1.7. _(Source: Write-up · Exhibit C (Dallol's brines) · Kotopoulou et al. (2019), A Polyextreme Hydrothermal System Controlled by Iron: The Case of Dallol at the Afar Triangle, ACS Earth and Space Chemistry (PMC))_ **Q: Which Danakil volcano hosts a perennial lava lake?** A: Erta Ale, farther south, hosts the lava lake. _(Source: Write-up · Exhibit E (The lava lake is elsewhere) · Smithsonian Global Volcanism Program: Dallol; Cavalazzi et al. (2019), The Dallol Geothermal Area, Northern Afar (Ethiopia): An Exceptional Planetary Field Analog on Earth, Astrobiology)_ **Q: How far below sea level does the Depression reach?** A: It reaches around 124 m below sea level at Lake Assale and near Dallol. _(Source: Write-up · Exhibit A (Below sea level) · Cavalazzi et al. (2019), The Dallol Geothermal Area, Northern Afar (Ethiopia): An Exceptional Planetary Field Analog on Earth, Astrobiology)_ **Q: What is the area's mean annual temperature?** A: About 35 °C, with a hot desert climate. _(Source: Write-up · Exhibit B (Hot and dry) · Kotopoulou et al. (2019), A Polyextreme Hydrothermal System Controlled by Iron: The Case of Dallol at the Afar Triangle, ACS Earth and Space Chemistry (PMC))_ ## Sources - [Kotopoulou et al. (2019), A Polyextreme Hydrothermal System Controlled by Iron: The Case of Dallol at the Afar Triangle, ACS Earth and Space Chemistry (PMC)](https://pmc.ncbi.nlm.nih.gov/articles/PMC6380227/) - [Cavalazzi et al. (2019), The Dallol Geothermal Area, Northern Afar (Ethiopia): An Exceptional Planetary Field Analog on Earth, Astrobiology](https://doi.org/10.1089/ast.2018.1926) - [Smithsonian Global Volcanism Program: Dallol](https://volcano.si.edu/volcano.cfm?vn=221041) ## Cite this case file Easterling, Marcus. "Danakil Depression." The Detail Department (DetailEnjoyer), case file DD-055, last updated May 30, 2025. https://detailenjoyer.com/case/danakil-depression/