The geology and geochemistry of the gypsum deposit in the Isinya-Konza areas Kajiado district-Kenya

Abstract

The geology and geochemistry of the Isinya-Konza gypsum deposits have been described and the area geologically mapped at a scale of 1: 25,000 as shown in the 2 geological maps and 3 cross-sections in the map pocket. An estimated reserve of gypsum nodules of about 330,000 tons at Isinya and 250,000 tons at Konza, has been established to occur in shallow isolated basins within the Tertiary Kapiti phonolites. The pattern of the basins are approximately aligned with the drainage system. The EDXRF analysis results of 80 samples of the gypsum, associated sediments and the host rocks has shown that, the mineralised zones have high values of lead (pb) and Bromide (Br), and very low values of Ca compared to the background values in the soils. The chemical formula of the gypsum has also been calculated