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Earth of fire

Actualité volcanique, Article de fond sur étude de volcan, tectonique, récits et photos de voyage

In northern Kenya , Lake Turkana , also called " Jade Sea " , is home to many volcanic landscape. First known as Lake Rudolf , in honor of the Crown Prince of Austria, it was discovered by Europeans in 1888, and was renamed Turkana after Kenya's independence in 1975 , in honor of the largest tribes living on its banks.

-Lake turkana satellite
            " The Jade Sea " - Lake Turkana encroach north of Ethiopia ( the border is thin overlay )
                                          Satellite image via Wikipedia / Roke .

Nabuyatom volcanoe Lac Turkana - veselok.ru
Nabuyatom volcano and the lava of the volcano Teleki / The barrier volc . compl. / South of Lake Turkana / Von Höhnel bay - Photo veselok.ru

Lake Turkana was at its peak here 9,000 years ; the lowest point was reached there 4,000 years ago , when he lost his major source and split into two entities.  He found today an intermediate level, 80% supplied by the Omo River which leads to the north and to the east, by the Turkwel river .

North Island is formed of a collection of tuff cones , dated 3.25 Ma, North Islandwhich exceed 220 m. the lake level . In its center, a young tuff ring is filled with dark brown trachytic lava which overflowed on its east side.

A fault line crosses the island from NE to SW., along which the geothermal activity is concentrated. Hot springs, fumaroles and sulfur springs are found in the southern part of North Island , 2 km long . In 2004, a geyser is described ... without activity report since.

Photo Oregonstate Univ. / Kenya Information Services.

Further south of Kenya, the Suguta river valley is separated from Lake Turkana by the Barrier volcanic complex, mainly trachytic , 15 km wide, and consists of four overlapping shield volcanoes , from west to east , the Kalolenyang, the Kakorinya, the Likaiu East and Likaiu West .

The barrier volcanic complex - GVP
       The Barrier volcanic complex, between the Lake Turkana and the Suguta Valley - Photo GVP

suguta valley et Logipi lake 2011.01.10 - EO1 AliThe dry Suguta valley and the lake Logipi - the cinder cones SANC and NAMC are part of The Barrier complex - the fine white line marks the maximum extension of the paleo- lake Suguta - Photo NASA EO- 1 Ali 10.01.2011

Suguta valley - Flickr skyscrapercity       Suguta valley - volcanic structure with waters colored by algae - Photo Skyscrapercity / Y.Garcin

There are a few thousand years this valley was filled by a paleo- lake ... since it has dried and is traversed by the seasonal river Suguta , which forms the temporary Alablad Lake , a dry lake that combines north of the valley with Logipi lake.
The Suguta river passes a place called The Gap , flanked by two volcanoes. It is fed by hot springs flowing on both sides of the valley. One of them , the geyser Logipi was active until the 30s , it was 1.2 m in height. An expedition to this remote area  found in 1990 only hot springs .

 

Lake Logipi- François-Olivier Dommergues

            Logipi lake bordered by lava flows- Photo François -Olivier Dommergues / Flickr FO travel

Volcanic-outcropping-set-in-dried-up-lake-with-flying-flami             Volcanic outcrop with Logipi lake in foreground - Photo wildencounters.net

The Suguta Valley is home to the shield volcano Namarunu, mainly trachytic. He wears parasite cones and lava, dating from late Pleistocene and Holocene, where a basaltic effusive and explosive activity took place along the axis of the African Rift, characterized by cinder cones, lava flows, sublacustres tuff rings, tuff cones and pillow lavas. A cinder cone forming the top of Namarunu issued olivine fluids basalts. The most recent eruption is dated there 3000 years ago, after the drying up of Lake Suguta .

Few pictures of geysers of this region , offset by the associated volcanoes ... Kenya second part tomorrow .

 

 

Sources :

- Wondermondo - geysers of Africa - link

- Global Volcanism Program - North island
- Global Volcanism Program - The Barrier
- Global Volcanism Program - Namarunu

- Science direct - Late pleistocene-Holocene rise a,d collapse of Lake Suguta, northern Kenya rift - by Yannick Garcin & al.

- Potsdam Univ. - Suguta valley project - link

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