About 140 miles northwest of Nairobi. Columnar jointing in pyroclastic rocks at Hells Gate National Park, near Lake Naivasha, Southwest Kenya. Columnar jointing consists of parallel prismatic columns that have polygonal cross sections. This type of jointing forms in thin volcanic rock bodies as a result of contraction during cooling of the extrusive magma. Diatomaceous lake beds at the edge of salty Lake Elmenteita.
Diatomaceous earth is a light colored soft friable siliceous sedimentary rock.
It consist of opal or quartz that formed the siliceous walls of diatoms, a microscopic single-celled plant. The rocks are mined for the diatomaceous earth that has high surface area, high absorptive capacity, and chemical stabilty, properties that find use as filters, and as extenders in paint, rubber, and plastics. About 130 miles northwest of Nairobi. Ol Karia Geothermal Field, near Lake Naivasha, about 80 miles northwest of Nairobi. Electrical energy is generated from the steam harnessed into pipes from underground water courses.