The Barrier Volcano - John Seach

john

(Andrew's volcano, Teleki's volcano)
Kenya

2.32 N, 36.57 E
summit elevation 1032 m
Shield volcano

The Barrier is composed of four overlapping shield volcanoes at the southern end on Lake Turkana, in northern Kenya. The volcano derives its name from its location which is between Lake Turkana and the Suguta Valley (the location of a former lake). The volcano is nearly symmetrical in N-S with slopes of 4-5 degrees.

The western rim of the inner caldera is 700 m above Lake Logipi (altitude 250 m) and the wall of the outer caldera is a further 80 m higher. The volcano separated from Lake Turkana 9600 years ago.

Teleki's volcano
This eruptive centre is located on the northern flank. Lava flows reach Lake Turkana.

Andrews Volcano (Lugugugut)
This eruptive centre is located on an early caldera fracture in the south.

Evolution of the Barrier Volcano
1) Formation of a basal shield volcano with a maximum thickness of 500 m.
2) An ash flow was deposited on the eastern flanks of the shield.
3) Tuff cones were built on the western and southern flanks.
4) A major eruption of basalt lava on the SE flanks of the volcano.
5) Formation of the first caldera (6 x 5 km).
6) Lava erupted in the caldera and spread out through a wide breach in the southern rim. Lava flowed eastwards past a low caldera rim.
7) Collapse of the inner caldera.
8) Recent volcanic activity in the caldera occurred around the northern rim.
9) Eruptions of lava and pyroclastics on northern and southern slopes.

1888 Eruption
In 1888 Cavendish and Andrew on an expedition to Lake Rudolf (Turkana) reported activity at the volcano.

"On their way they explored the salt Lake Sugota [Logipi], regarding which Cavendish reports as follows : It lies about 30 miles south from Lake Rudolf [Turkana]. Its shores are very barren, entirely enclosed by mountains, and there are three islands, apparently quite barren near the east shore. It is fed by two rivers. What water there was in this lake was exceedingly hot, and near to the north end, where a smouldering volcano was situated, was just as hot as one would like to wash one's hands in. This volcano I propose to call, after my companion, Andrew
Volcano... The altitude of the lake is 1,300 feet, and the height of the volcano 1,600 feet."

The Barrier Volcano Eruptions

1921, 1920?, 1917, 1906?, 1897, 1895, 1888, 1871, 1090, 1050, 1030