Thermal decomposition of Lokpanta oil shale from Nigeria was studied by non-isothermal thermogravimetry (TG) and differential thermal analysis (DTA). The experiments were performed in an inert environment with a temperature range of 25 to 600 degrees C. The geochemical characteristics of the oil shale were also investigated by Rock Eval. pyrolysis. Thermal breakdown of the kerogen content of the oil shale takes place mainly at the temperature range of 300 to 570 degrees C. The estimated decomposable kerogen content of the oil shale ranges from 4.55 to 9.64 wt.%. The activation energies of the pyrolysis process vary from 73.2 to 75.0 kJ/mol. The DTA data reveals the exothermic nature of the decomposition process. The results from the geochemical analysis indicate that the oil shale contains sufficient, good quality kerogen to generate both oil and gas upon pyrolysis. (c) 2005 Elsevier Ltd. All rights reserved.