Understanding the hydrocarbon-generation potential on jurassic coal-measure source rocks in the Junggar Basin: From the perspective of hydrogen-rich molecular structure  

作　　者：Tian-Chen Ge Xiang-Chun Chang Guan-Long Zhang Jun-Jian Zhang Rui-Chao Guo Wei-Zheng Gao Ling-Yu Zhao Shang-Bin Wang Jia-Qi Duan 

机构地区：[1]College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao,266590,Shandong,China [2]Laboratory for Marine Mineral Resources,Qingdao Marine Science and Technology Center,Qingdao,266237,Shandong,China [3]Research Institute of Petroleum Exploration and Development,Shengli Oil Company,Sinopec,Dongying,257001,Shandong,China [4]School of Geology and Mining Engineering,Xinjiang University,Urumqi,830017,Xinjiang,China

出　　处：《Petroleum Science》2024年第5期2969-2983,共15页石油科学（英文版）

基　　金：co-funded by the National Natural Science Foundation of China (Grant Nos. 42372160, 42072172);Shandong Province Natural Science Fund for Distinguished Young Scholars (Grant No. JQ201311);the Graduate Scientific and Technological Innovation Project financially supported by Shandong University of Science and Technology (Grant No. SDKDYC190313)。

摘　　要：The Jurassic coal-measure source rocks in the Junggar Basin have drawn considerable attention in recent years. In our hydrocarbon thermal simulation experiments of these rocks, we found that the dark mudstone evaluated as good source rock, had a much lower hydrocarbon generation capacity than the coal and carbonaceous mudstone, evaluated as poor source rock. Based on this background, we performed Fourier transform infrared spectroscopy(FTIR) and combined the results of semi-open thermal simulation experiments to explore the association between the molecular structure and hydrocarbon production capacity, with the aim of obtaining a new understanding of hydrocarbon potential of Jurassic coal-measure source rocks from the perspective of molecular structure. The results indicate that coals exhibit lower condensation of aromatic structures and higher relative abundance of aliphatic structures with a higher degree of branched chaining than mudstones and carbonaceous mudstones. Apparent aromaticity(f_a), aromatic abundance parameter I, and degree of condensation(DOC) are negatively correlated with organic matter abundance. The aliphatic structural parameter H demonstrates a substantial positive correlation with organic matter abundance. Furthermore, aliphatic relative abundance factor A is associated with the type of organic matter;the better is the type of the organic matter, the larger is the A value. The combination of the molecular structures with the thermal simulation results shows that the aliphatic hydrogen enrichment of selected carbonaceous mudstone is similar to that of coal. However, the relative abundance of the aliphatic group of it is high, and the DOC of the aromatic structure is low, making the hydrocarbon generation base stronger and easier to crack. Thus, the hydrocarbon generation capacity of carbonaceous mudstone is slightly higher than that of coal. Mudstone has low H and I values, and the DOC is high, indicating that its hydrocarbon base is low, so it has low hydrocarbon generation capacity. There

关 键 词：Coal-measure source rock Hydrocarbon potential Macromolecular structure Semi-open system pyrolysis Junggar basin 

分 类 号：P618.13[天文地球—矿床学]