Exploring the thermal evolution of highly-to over-mature source rocks using Raman spectroscopy and geochemical signaturesOA
This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical signatures of shales from the Lower Silurian Longmaxi Formation and the Lower Cambrian Qiongzhusi Formation,as well as anthracites from the Lower Permian Shanxi–Formation and the Upper Carboniferous Taiyuan Formation(collectively referred to as the Shanxi Taiyuan Formations).Additionally,burial and thermal evolution modeling was employed to support the analysis.A systematic assessment of Raman spectral parameters(e.g.,the positions and intensity ratio of the D and G bands)revealed robust correlations between the thermal history patterns of source rocks and molecular structural evolution parameters.The subsequent mechanistic quantification demonstrated that the maturation state of the source rocks was subjected to the hierarchical control of three principal factors:Peak heating temperature,the duration of sustained thermal intensity,and effective maturation duration.In addition,comparative analyses demonstrated that the anthracites attained higher structural ordering under sustained thermal conditions.This contrasts with the disordered carbon matrices observed in the intermittently heated shales.Raman spectroscopy further revealed broader variations in the D and G band intensities of the Longmaxi Formation compared to the Qiongzhusi Formation.This difference is associated with their different thermal histories.The thermal burial histories confirm that shales in the Longmaxi Formation underwent thermal exposure at lower peak temperatures over a shorter duration compared to those in the Qiongzhusi Formation.Finally,this study established a maturity calibration model for over-mature source rocks through a systematic correlation between Raman peak height ratios(R_(D/G))and vitrinite reflectance(R_(o)).
Fu-hua Shang;Xiao-peng Sun;Shu-wei Ma;Yu-tong Pang;Guan-qun Zhou;Ke Miao
Inner Mongolia Engineering Research Center of Geological Technology and Geotechnical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China Mine Geology and Environment Academician and Expert Workstation,Ordos Institute of Technology,Ordos 017000,China Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi’an 710018,ChinaInner Mongolia Engineering Research Center of Geological Technology and Geotechnical Engineering,Inner Mongolia University of Technology,Hohhot 010051,ChinaResearch Institute of Exploration and Development,Changqing Oilfield Company,PetroChina,Xi’an 710018,ChinaMine Geology and Environment Academician and Expert Workstation,Ordos Institute of Technology,Ordos 017000,ChinaSchool of Resources and Environmental Engineering,Hefei University of Technology,Hefei 230009,ChinaInner Mongolia Engineering Research Center of Geological Technology and Geotechnical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China
天文与地球科学
Raman spectroscopyOvermature source rockQiongzhusi FormationLongmaxi FormationAnthraciteMineral exploration engineering
《China Geology》 2026 (1)
P.75-85,11
supported by the National Natural Science Foundation of China(42362022)the Open Fund of the Shaanxi Key Laboratory of Petroleum Accumulation Geology(PAG-202406)the Open Fund of the Mine Geology and Environment Academician and Expert Workstation(2024OITYSZJGZZ-005)。
评论