Control mechanisms of kerogen chemical structure on thermogenic gas generation

Abstract

Kerogen is the primary organic component responsible for hydrocarbon generation, influencing the hydrocarbon potential and characteristics of source rocks. While previous studies have mainly focused on comparing hydrocarbon generation across different kerogen types, the impact of kerogen's microstructural features on hydrocarbon generation has received less attention. In this study, hydrocarbon source rocks from the Shuixigou Group (Turpan-Hami Basin) were analyzed using pyrolysis, Fourier Transform Infrared Spectroscopy (FTIR), and open-system thermal simulation to investigate the influence of kerogen's chemical structure on hydrocarbon generation. The results indicate that the ratio of main to branched chains in kerogen influences hydrocarbon generation capacity and gas yield potential. Kerogen with a higher branched chain content is more prone to generating gaseous hydrocarbons. Specifically, humic kerogen, characterized by a high abundance of branched chains, leads to higher gas generation potential. This study highlights the relationship between kerogen's microstructural features and its hydrocarbon generation potential, offering insights into the hydrocarbon potential of source rocks and the development of natural gas fields in the Turpan-Hami Basin.