The Dallol Volcano is a strange piece of nature’s artwork
Sulfur, salt, and other minerals color the crater of Dallol Volcano, part of the Danakil Depression in Ethiopia. At 157 feet (48 meters) below sea level, Dallol is Earth’s lowest land volcano. Many of these photos look like they were taken from a different planet. (Pics)
Dallol volcano is located in the Danakil Depression in NE Ethiopia, in a remote area subject to the highest average temperatures on the planet. The volcano encompasses Dallol mountain (which rises 50-60m above the surrounding salt plains and has approximate dimensions of 1.5 x 3 km) and several other features in the vicinity, such as the 1926 crater near the “Black Mountain” about 1.5 km to the SW. Dallol is nested on top of an at least 1000m thick layer of quaternary evaporates including large potash (potassium salt) reserves, the source of which will be discussed in more detail below.
View from Black Mountain over 1926 crater to Dallol mountain
The 1926 phreatic eruption formed a 30m wide crater and was the last significant event at Dallol. Currently, activity is in the form of hot brine springs. Salts washed out of the underlying layers are transported to the surface by geothermally heated water and rapidly crystallize as the water evaporates. The characteristic white, yellow and red colors are the result of sulfur and potassium salts colored by various ions. The terminology Dallol is often used to define an even larger area, which may cause confusion as to the location of mining operations in the area.
Remains of hot spring with Black Mountain on left and Dallol Mountain in background
Dallol mountain is thought to have been formed as the result of intrusion of a basaltic magma body underneath. The circular depression near the center of Dallol mountain is presumably a collapse crater, although neither its age nor the exact process from which it resulted are known. The SW flank of Dallol mountain harbors impressive salt canyons formed by erosion processes.
The Danakil Depression is located in what is effectively a northerly extension of the East African Rift Zone. It lies in the gap resulting from gradual separation of the Danakil horst from the Ethiopian Plateau. Since the area lies up to 120m below sea level, it has been repeatedly flooded when the ongoing rifting process allowed transient entry of waters from the Red Sea.
Following each flooding episode, partial or complete evaporation of the sea-water resulted in thick deposits of salt. These deposits are highly stratified, since when large bodies of salt water evaporate, precipitation of carbonate, sulphate and chloride salts of sodium, calcium, magnesium and potassium occurs at different stages of the evaporation process.
The potash deposits cannot be accounted for by simple evaporation of sea-water, but are thought to result from rising of hydrothermal brines into the overlying sea-water during the evaporation process
The primary (i.e. sedimentary) potash deposits in the Dallol area are usually overlain with other evaporates, and the entire area around Dallol is covered at the surface by alternating layers of halite and mud to a depth of several meters.
Alternating layers of halite and mud
This “crust” results from the periodic flooding of the area by sediment-rich waters from the nearby highlands and subsequent dessication.
The colorful springs on Dallol mountain
The colorful springs on Dallol mountain derive their colors mainly from ferrous chloride and iron hydroxide (both white-greenish), ferric chloride (yellow-brown) and iron oxide (brown).
Hot Springs on Dallol Mountain
Steam coming off hot spring
Water jetting out of small hot spring by pool
Cluster of tiny hot springs
Beautiful color trails coming from the hot springs
Scenes from another planet
Hot Spring Deposits, Dallol Mountain
The beautiful hot springs at Dallol are attracting increasing numbers of tourists, with many tour operators organizing tours into the Danakil Depression to see the Springs and Erta Ale volcano further south. Dallol can presently be reached by 4WD vehicle in 1 day from Mekele and 2 days from the main Addis-Djibouti road. However, 2007 and 2008 have seen repeated attacks on tourist convoys by what appear to be Afar Separatists from the Afar Revolutionary Democratic Unity Front (ARDUF). The establishment of improved infrastructure may increase security, yet even the current small stream of tourists is causing visible damage to the fine structures in the geothermal area.
Via Photo Gallery