Determination of total organic carbon content using Passey's method in coals of the central Kalahari Karoo Basin, Botswana

This paper focuses on determining total organic carbon (TOC) from boreholes in the Kalahari Basin, Botswana, using Passey's method. The Karoo basin is one of several basins southern Africa filled with Late Carboniferous to Jurassic sedimentary strata that host Permian age coal seams. Nine exploration (wells) drilled central are used determine Total Organic Carbon potential. Vitrinite reflectance (Ro), proximate and ultimate analyses were conducted cored intervals. ΔLogR method applied this study employs resistivity porosity logs identify quantify potential source rocks. Results compared laboratory-measured showed effectively identifies In terms TOC calculations, works poorly metamorphosed by dolerite intrusions. heat affected samples had Ro 0.77% 5.53% increased maturity primarily maceral controlled high volatile bituminous anthracite coal. analysis compositional changes proximity sill intrusion, a decrease Fixed an increase ash yield contact metamorphism zone (2–12 m sill). For unaltered has undergone burial maturation displaying 0.44%–0.65%, well. unintruded boreholes, correlations between calculated indicate strong relationships. proved be suitable estimating maturation. demonstrated sonic log more reliable not than density log.