The geology of Djibouti consists largely of

volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcanic r ...

s from the

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togethe ...

epochs. There are more recent alluvial deposits with

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...

on the coast, as well as

Cenozoic The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configura ...

sedimentary.

Amba Aradam Amba Aradam is a table mountain in northern Ethiopia. Located in the Debub Misraqawi (Southeastern) Zone of the Tigray Region, between Mek'ele and Addis Abeba, it has a latitude and longitude of and an elevation of . The name in Tigrinya is ...

Sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

s from the

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The J ...

Period are found in the southeast of the country.

Geologic overview

The country was formed by the collision of general tectonic trends of the

East African Rift The East African Rift (EAR) or East African Rift System (EARS) is an active continental rift zone in East Africa. The EAR began developing around the onset of the Miocene, 22–25 million years ago. In the past it was considered to be part of a ...

. The rift generated fragmented relief made up of high blocks and subsidence zones, which create geological features such as Lake Assal.

Tectonics

The Red Sea Gulf of the Aden split open during the Pliocene and early Pleistocene epochs. During these epochs, the Danakil Horst experienced an uplift of its southern prolongation. Analysis of plate tectonics at the triple junction region shows extension rates between 1 mm and 3 mm annually. Earthquake epicenters are focused along the peripheral block faults where the Ethiopian rift touches the Red Sea and Gulf of Aden.

Geosites

A detailed investigation into the geosites available in Djibouti has not been performed yet, however the triple junction located at the East African Rift System is considered to be of significant geological interest.

Geohazards

Volcanic eruptions and earthquakes occur at the triple junction at the East African Rift System.

Economic impact

Although Djibouti produces minerals, it is an insignificant portion of its economy. Salt, available due to solar evaporation, is harvested at Lake Assal and helps to make the country

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

’s tenth largest salt producer. Limestone and calcined lime are also currently mined in Djibouti. Additional mining candidates include marble, granite, gypsum,

diatomite Diatomaceous earth (), diatomite (), or kieselgur/kieselguhr is a naturally occurring, soft, siliceous sedimentary rock that can be crumbled into a fine white to off-white powder. It has a particle size ranging from more than 3 μm to le ...

and perlite. Petroleum could be extracted in the future; currently exploratory work is being performed. In addition to mining, the possibility of using geothermal energy is currently being investigated.

Education

Djibouti's new university does have courses available in geology or geosciences.

References

{{Africa topic, Geology of Geography of Djibouti