Geochemical Assessment for the Morendat East Geothermal Prospect

Abstract

Geochemical assessment was carried out at the Morendat East geothermal prospect by characterizing radon (220Rn) and carbon dioxide (CO2) concentration levels from soil-gas survey. The primary aim was to locate permeable zones and infer the presence of possible heat source linked to an active geothermal system. The secondary aim was to rank the prospect and facilitate its development by the private sector. This study focused on the distribution of Radon and Carbon dioxide concentration levels in the soil cover within Morendat East area located in Nakuru County. The area was considered as having potential for geothermal resource hence priority was accorded to it in the financial Year 2014/2015 by the ministry of energy and petroleum. The location is characterized by scarcity of surface geothermal manifestations with one warm spring, therefore soil gas survey was considered appropriate for the geochemical study. Random sampling method was used and resulted in the sampling 100 stations in an area of about 90 square kilometers. CO2 concentration measurements from the soil were done using an Orsat gas sampling apparatus whereas 220Rn gas concentrations were measured using a portable radon detector (emanometer).The CO2 values ranged from 0-5.4% while the 220Rn ranged from 0- 2834 cpm. Possible faults were inferred north of the prospect area due to the anomalously high levels of CO2 and 220Rn recorded.