Mount Silali is part of a group of volcanoes, the others being
Paka and
Korosi, in the Loyamoruk Plains of the eastern Nginyang Division of
Baringo County. 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 volcano in the Gregory Rift Valley. Its pre-caldera development began with mainly
peralkaline trachyte lavas and
pyroclasts, succeeded by mildly alkaline to transitional
basalts. The basalts of the mountain are similar in composition to
oceanic island basalts, but have a range of
isotopes 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,
domes 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==