I plan to artificially mature kerogen to different thermal maturity levels to generate samples covering a wide range of maturity levels. For the current study, I propose to use anhydrous pyrolysis which is performed by systematically heating the kerogen sample in a closed system in the absence of oxygen. The advantage of anhydrous pyrolysis is that large sample sizes can be pyrolyzed reactively to simulate natural maturation process . ). Among these, XPS is widely used in chemical structure analysis for its ability to efficiently observe elemental composition and functional group information on the surface within 10 nm and is one of the most effective methods for element investigation . used XPS for geochemical characterization of kerogen and showed that organic oxygen content in kerogen decreases as it becomes more thermally mature. Pyrolysis is the process of decomposition of organic matter by heating and is regularly used in petroleum geochemistry to measure total organic carbon content (TOC) and other properties such as hydrogen index (HI) and Tmax for characterization of thermal maturity of organic matter.