Erta Ale

Dallol: Hot springs

Geologically, Dallol is a most remarkable place: Situated in the Danakil depression, it is nearly 120 meters below sea level. Below a salt lake is a substantial source of volcanic heat which causes hot water to rise through layers of salt and anhydrite deposits. Minerals get dissolved and are deposited, near the springs, and form shapes very much reminiscent (but smaller than) hornitos on basaltic lava flows. Sulphur, other minerals and possibly thermophyle bacteria cause spectacular colours.

Dallol: Hot springs
Typical group of active «hornitos» up to about one meter high.
Dallol: Hot springs
Boiling water spurts out from an active «hornito».
Dallol: Hot springs
Fresh deposits form bright yellow terraces, while older deposits (background) have become brown due to weathering.
Dallol: Hot springs
Some of the larger terraces dam ponds of up to about one meter in diameter.
Dallol: Hot springs
Old, inactive «hornitos» quickly lose their lustre and gradually turn beige and, later, brown.
Dallol: Hot springs
Contrast between youngest deposits (white), a little older (yellow) and several months old (brown or black; background).
Dallol: Hot springs
Typically Dallol springs form small clusters building up miniature «citadels» like the one in the foreground and another further back.
Dallol: Hot springs
Alien sculptures on display in an alien landscape. Are we still on planet Earth?
Dallol: Hot springs
In this remarkable small, green pond particularly large salt crystals are forming.
Dallol: Hot springs
Thin floes of salt on the surface of this pond may have formed at night due to lower temperatures and lower solubility in the water.
Dallol: Hot springs
A somewhat more substantial floe adorns this jewel of a pond. During the midday heat it all dissolved in the water.
Dallol: Hot springs
One of the flat, low areas where the water from the springs ends up and gradually evaporates.
Dallol: Hot springs
«Mineral exhibition» in the desert: Salt and sulphur crystals.
Dallol: Hot springs
Eggs of aliens? Remarkable mineral deposits around small scale steam vents.
Dallol: Hot springs
A larger, complex, «egg» all on its own.
Dallol: Hot springs
Roby's set-up for videography. The microphone records noises from the spring.
Dallol: Hot springs
Tiny salt stalactites have been sculptured by the strong desert winds.
Dallol: Hot springs
The green ponds amongst the orange and yellow sulfur and salt deposits were our favorite features at Dallol.
Dallol: Hot springs
And also a second picture of the «green pond» after the salt floe has disappeared.
Dallol: Hot springs
Minerals probably other than salt have crystallized around a minute crack in the ground.