The objective of this research was to investigate thermal behavior and kinetics of different origin crude oils in limestone matrix by differential scanning calorimeter (DSC) at low heating rates. In DSC experiments, three distinct reaction regions were identified in all of the crude oil + limestone mixtures known as low temperature oxidation (LTO), fuel deposition (FD) and high temperature oxidation (HTO) respectively. Kinetic analysis of the crude oil samples was determined by different models known as ASTM. Borchard-Daniels and Ozawa. Higher activation energy values were obtained in high temperature oxidation region. (C) 2011 Elsevier B.V. All rights reserved.