Scientists Uncover Biogeochemical Controls on Occurrence and Distribution of PACs in Coals

Typography

The organic matter in coal contains polycyclic aromatic compounds (PACs) of varying quantities in diverse soluble and insoluble forms. PACs in coal are of special interest for organic geochemical studies as they have been successfully used as biological marker compounds (biomarkers) and indicators of thermal maturity.

However, challenges exist when applying PACs in understanding the organic geochemistry of coal. For example, what are the sources of PACs in coals? How do they transform during the long-term coal-formation history? Is there any regular relationship between the PAC and macro-molecular structural changes? 

The organic matter in coal contains polycyclic aromatic compounds (PACs) of varying quantities in diverse soluble and insoluble forms. PACs in coal are of special interest for organic geochemical studies as they have been successfully used as biological marker compounds (biomarkers) and indicators of thermal maturity.

However, challenges exist when applying PACs in understanding the organic geochemistry of coal. For example, what are the sources of PACs in coals? How do they transform during the long-term coal-formation history? Is there any regular relationship between the PAC and macro-molecular structural changes? 

Researchers from the University of Science and Technology of China (USTC) revealed the close relationships between the distribution of PACs in coals and the process of coal formation, which is beneficial for identifying the origin of PACs and their role as biomarkers.?

Recently, a collaborative research group led by Dr. WANG Ruwei at USTC of Chinese Academy of Sciences and Dr. SUN Ruoyu at Tianjin University reviewed the application of geochemical parameters of PACs in coal as useful tools to trace the coalification process from the molecular perspectives, and to understand the biogeochemical processes (e.g. depositional environment, geological settings, igneous intrusion) occurring during coal formation. The study was published in Earth-Science Reviews.

Read more at University of Science and Technology of China

Image: Proposed evolution processes of PAH in magmatic-affected coal of different rank. (Provided by WANG Ruwei)