Korili: the hot springs of the Lake Assal sector

We publish no temperature for Korili. The figures in circulation are attached to no published, consultable measurement. The readings we found in the geological literature concern the hot stream that flows out of the springs, and not the springs themselves. The page therefore describes what can be observed — very hot water, abundant steam, fumaroles — without giving any degrees.

Where are the Korili hot springs?

Korili lies in the Lake Assal sector, Tadjourah region. The Dalmar catalogue ties the site to Lake Assal and places its coordinates at 11.604 N and 42.414 E, near the Ardoukoba volcano and the salt pans.

The setting is that of a rift floor: steep mountains, cliffs, basaltic flows and evaporite deposits. The springs emerge along a fracture that extends towards the south-east. It is that fracture which explains the geometry of the site: the water outflows are not scattered, they align.

What do you see at Korili?

The site reads as a succession of phenomena linked to the same hot water.

The travertine chimneys. They form an alignment along the fracture. These are structures built by the water itself, laden with calcium ions, and not volcanic rocks.

The fumaroles and steam. The steam emissions signal the springs from a distance and give the site its unsettling look. They are particularly visible in the cool hours.

The salt formations. Nearby, the water deposits carbonated salt flowers and, in the alluvium, eggshell crystallisations formed by capillary rise.

The hot stream. The water flows towards the lake and forms an environment the geological literature describes as sapropelic, with a bacterial and algal film and gas releases linked to photosynthetic activity.

Reference	Data	Source
Region	Tadjourah	Dalmar catalogue
Sector	Lake Assal (catalogue address)	Dalmar catalogue
Coordinates	11.604 N — 42.414 E	Dalmar catalogue
Nature of the site	Hydrothermal springs on a fracture	Dalmar catalogue and Berger
Formations	Travertine chimneys aligned towards the south-east	Berger
Mechanism	Water laden with calcium ions, carbonatogenic bacteria, a higher lake level	Berger
Salts	Carbonated salt flowers, eggshell crystallisation	Dalmar catalogue and Berger
Period of the crystallisations	Frequent between December and April	Berger
Facilities	None described in the catalogue	Dalmar catalogue

Why does Korili interest geologists?

Three things can be read here.

First an ancient lake level. The travertine chimneys were built underwater, in the presence of carbonatogenic bacteria, at a time when Lake Assal was higher. The site is therefore a palaeo-level marker: it documents a geometry of the lake that no longer exists.

Then an extreme environment. The geological literature notes thermophilic bacteria at Korili, that is, organisms that develop in environments once believed closed to life.

Finally an archive of the fault. Above the springs, the fault carries limestone encrustations of hydrothermal origin, and the sector shows an unusual succession: a recent basaltic flow covers a diatomite limestone deposit more than two metres thick, itself laid on volcano-detrital deposits. In the background stands the eroded edifice of Gale le Kôma, made of hyaloclastites covered by a thin basaltic flow.

How do you visit Korili?

The catalogue describes neither ticketing nor a visitor structure. So bring your own water, sun protection and closed shoes, and treat the visit as a field stage, not an equipped attraction.

In practice, Korili is visited as part of a Lake Assal excursion: the site belongs to the same sector, and the stop is made on the route leading to the salt pans. The Lake Assal page details access to the sector and the fact that the last kilometres are on track; Goubet al-Kharab and Ardoukoba naturally complete the same day.

Two elementary precautions. Do not put your hands in the water of the vents, and keep children at a distance: nothing marks the water outflows. Do not walk on the travertine chimneys, which are fragile and irreplaceable.

When should you observe the salt flowers?

Eggshell crystallisation, in the alluvium near the springs, is described as frequent between December and April. That is also the most comfortable period for crossing the sector: the heat of the basin becomes hard to bear from spring onwards.

As everywhere around Lake Assal, set off early. The page when to go to Djibouti gives the month-by-month detail, and the Tadjourah page covers the rest of the regional hinterland.