Mount Silali is a dormant

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

in the Gregory Rift Valley, near Kapedo,

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

. Silali is south of the

Suguta Valley The Suguta Valley, also known as the Suguta Mud Flats, is an arid part of the Great Rift Valley in Kenya (Africa), directly south of Lake Turkana. Location The Suguta valley today is one of the driest parts of Kenya, with annual rainfall below ...

, which reaches northward to

Lake Turkana Lake Turkana () is a saline lake in the Kenyan Rift Valley, in northern Kenya, with its far northern end crossing into Ethiopia. It is the world's largest permanent desert lake and the world's largest alkaline lake. By volume it is the world ...

, and is about north of

Lake Baringo Lake Baringo is, after Lake Turkana, the most northern of the Kenyan Rift Valley lakes, with a surface area of and an elevation of . The lake is fed by several rivers: the Molo River, Molo, Perkerra River, Perkerra and Ol Arabel. It has no obvio ...

Geology

Mount Silali is part of a group of volcanoes, the others being

Paka Paka may refer to: Places Europe * Paka (river), a river in northern Slovenia * Paka, Mislinja, a settlement in the Municipality of Mislinja, Slovenia * Paka pri Predgradu, a settlement in the Municipality of Kočevje, Slovenia * Paka pri Vel ...

and Korosi, in the Loyamoruk Plains of the eastern Nginyang Division of

Baringo County Baringo County is one of the 47 Counties of Kenya, counties in Kenya. It is located in the former Rift Valley Province. Its headquarters and largest town is Kabarnet. The county is home to Lake Baringo, Lake Bogoria and Lake Kamnarok. Geographi ...

. Silali is a recent volcano that became active from 400,000 to 220,000 years ago, and was still active 7,000 years ago. It is the largest

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the str ...

volcano in the Gregory Rift Valley. Its pre-caldera development began with mainly

peralkaline Peralkaline rocks include those igneous rocks which have a deficiency of aluminium such that sodium and potassium are in excess of that needed for feldspar. The presence of aegerine (sodium pyroxene) and riebeckite (sodium amphibole) are indicat ...

trachyte Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanite, aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava (or shallow intrus ...

lavas and

pyroclast Tephra is fragmental material produced by a Volcano, volcanic eruption regardless of composition, fragment size, or emplacement mechanism. Volcanologists also refer to airborne fragments as pyroclasts. Once clasts have fallen to the ground, ...

s, succeeded by mildly alkaline to transitional

basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

s. The basalts of the mountain are similar in composition to oceanic island basalts, but have a range of

isotope Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemica ...

s indicating a variety of origins. The Kenya rift is oriented north-south, and in the past the minimum horizontal tectonic stress direction was east-west, the direction of extension. The alignment of rows of recently formed small vents,

cones In geometry, a cone is a three-dimensional figure that tapers smoothly from a flat base (typically a circle) to a point not contained in the base, called the ''apex'' or '' vertex''. A cone is formed by a set of line segments, half-lines, ...

domes A dome () is an architectural element similar to the hollow upper half of a sphere. There is significant overlap with the term cupola, which may also refer to a dome or a structure on top of a dome. The precise definition of a dome has been a m ...

and collapse pits in the Silali region indicates that the minimum horizontal stress direction has changed to NW-SE within the last half million years.

Environment

Mean annual temperature in the Loyamoruk Plains is , rising to in the hot season. Rainfall averages , with wide variations. The thorn-bush savannah plain has no permanent source of water, with the Nginyang River flowing only after rains. There are some highland pastures on Mount Silali with perennial grasses. From oral accounts, the environment has become significantly drier in the last few decades, and with less grass and fewer types of grass.

Energy potential

The mountain is potentially a source of

geothermal energy Geothermal energy is thermal energy extracted from the crust (geology), crust. It combines energy from the formation of the planet and from radioactive decay. Geothermal energy has been exploited as a source of heat and/or electric power for m ...

. There are

hot spring A hot spring, hydrothermal spring, or geothermal spring is a Spring (hydrology), spring produced by the emergence of Geothermal activity, geothermally heated groundwater onto the surface of the Earth. The groundwater is heated either by shallow ...

s at Kapedo to the west with temperatures of to . The eastern part has many

fumarole A fumarole (or fumerole) is a vent in the surface of the Earth or another rocky planet from which hot volcanic gases and vapors are emitted, without any accompanying liquids or solids. Fumaroles are characteristic of the late stages of volcani ...

s and hot and altered grounds with temperatures that range from to . In September 2011 the Geothermal Development Company (GDC) of Kenya said that 19 companies had submitted bids to develop

geothermal power Geothermal power is electricity generation, electrical power generated from geothermal energy. Technologies in use include dry steam power stations, flash steam power stations and binary cycle power stations. Geothermal electricity generation i ...

plants at

Lake Bogoria Lake Bogoria (formerly Lake Hannington) is a saline, alkaline lake that lies in a volcanic region in a half-graben basin south of Lake Baringo, Kenya, a little north of the equator. Lake Bogoria, like Lake Nakuru, Lake Elementeita, and Lake Ma ...

and at Silali. GDC intended to choose eight companies, each to build one 100 MW power plant. They expected the plants to start coming on line in 2017.

References

Sources

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External links

* {{DEFAULTSORT:Silali Volcanoes of Kenya Dormant volcanoes Baringo County Shield volcanoes of Africa