Dalol: Earth's blazing puzzle - boiling depths, toxic fumes and life's secrets

New Delhi (The Uttam Hindu): There are many places around the world where nature offers not only beauty but also dangerous and mysterious glimpses. The Dallol region, located in Ethiopia's Danakil Depression, is one of the most dangerous and unique places on Earth. The hydrothermal system here includes salt chimneys, hot springs, and extremely acidic water. The Dallol region is located on the crater of a salt-filled volcano. Due to hydrothermal activity, boiling water and toxic gases continuously emerge from this crater.

According to the US space agency NASA, the area appears colorful and psychedelic. Yellow deposits are made of sulfate, red areas are iron oxide, and copper salts give the water its green color. The supersaturated water reaches temperatures of over 94 degrees Celsius, and the pH level drops to 0.25, which is extremely acidic. The area is also highly salty, where salt chimneys are common.

An international team led by Dr. Felipe Gomez of the Astrobiology Center in Spain studied the area. Samples were taken during a field trip to Ethiopia in January 2017. The results were published in the journal Scientific Reports. The team collected samples from salt deposits on the walls of yellow salt chimneys and from the surrounding blue water pools. These were transported to Spain in sterile vials and analyzed using electron microscopy, chemical analysis, and DNA sequencing. Scientists recently discovered tiny bacteria that survive and thrive in these harsh conditions.

Scientists found small, spherical structures in the salt sample that contained high amounts of carbon. These structures were of biological origin. These bacteria are up to 20 times smaller than normal bacteria. Dr. Gomez explained, “This is a unique multi-extreme environment. Here, organisms have to survive in extreme temperatures, high salt levels, and very low pH. These bacteria love these conditions. This raises the question: have they adapted to these conditions or have they evolved from them?”

Dallol is approximately 125-155 meters below sea level. Geological activity here causes hot water, minerals, and gases to rise to the surface. The area is spread around a small volcano that formed in 1926. Dallol is considered the hottest inhabited place on Earth. The average temperature here is 34-35 degrees Celsius year-round. The water in the hot springs boils, emitting highly acidic, salty, and toxic gases. The colorful minerals (yellow, red, green) make it look like another planet. Toxic gases like chlorine and sulfur linger in the air. This area is so harsh that it is almost impossible for human life, yet microorganisms survive here.

Scientists consider it an excellent analogue of Mars's ancient atmosphere because of its similar hydrothermal activity, acidity, and mineralogy. The Danakil Depression is one of the hottest regions in the world due to its equatorial location, volcanic activity, and location below sea level. Minerals such as silver chloride, zinc iron sulfide, manganese dioxide, and rock salt precipitate from the superheated water. This discovery adds to the world of extremophiles.

There are many organisms on Earth that can survive radiation, ice depths, atmospheric altitudes, or even spacecraft. The Dallol region resembles places like Gusev Crater on Mars, where NASA's Spirit rover landed. The team also published a review in the journal Astrobiology, noting the similarities between Dallol and Mars' hydrothermal environments.