The Permian Dalong Formation(P2d) source rocks from the mature Guangyuan outcrop section and the overmature Wangcang outcrop section in Sichuan Basin were selected.The Soxhlet extraction and kerogen catalytic HyPy wer...The Permian Dalong Formation(P2d) source rocks from the mature Guangyuan outcrop section and the overmature Wangcang outcrop section in Sichuan Basin were selected.The Soxhlet extraction and kerogen catalytic HyPy were conducted on the P2d source rocks.The biomarkers obtained by both methods were compared to discuss their difference and the influence extent of thermal maturation on covalently bound biomarkers.The results show that covalently bound biomarkers can hardly be correlated to the corresponding free biomarkers due to severe thermal alterations and/or interference of migrated hydrocarbons in both outcrop sections and thermal maturation have much lower influence on covalently bound biomarkers in kerogens than on free biomarkers in Soxhlet extracts.The application of HyPy in study of biomarker geochemistry can reduce the thermal maturation effect on biomarkers(Ro≤2.4%) to a greater extent and the interference of migrated hydrocarbons between interbedded layers.The covalently bound biomarkers released by HyPy are useful in the study of biomarker geochemistry and oil-source correlation on high-overmature source rocks.展开更多
The compositional and structural changes that coal asphaltenes undergo with increasing thermal maturation were investigated using solid-state13 C NMR and Fourier transform infrared spectroscopy. The results show a gra...The compositional and structural changes that coal asphaltenes undergo with increasing thermal maturation were investigated using solid-state13 C NMR and Fourier transform infrared spectroscopy. The results show a gradual increase in the relative proportion of carbon content with a concomitant decrease in the hydrogen, sulphur and oxygen content. The amount of aromatic carbon also increases while the aliphatic carbon decreases with increasing maturity. Ester and carboxylic groups are particularly sensitive to maturation and decrease in relative abundance with increasing maturity while the amount of aromatic carbonyl groups increases. In general, the asphaltenes were observed to evolve towards a more thermally stable structure with increasing amounts of aromatic moieties and relatively lower amounts of aliphatic moieties. The results are in agreement with the ultimate dominance of the island molecular architecture(the Yen–Mullins model) in asphaltenes.展开更多
基金supported by the National Science and Technology Major Project(2011ZX05008-002 and 2011ZX05005-001)
文摘The Permian Dalong Formation(P2d) source rocks from the mature Guangyuan outcrop section and the overmature Wangcang outcrop section in Sichuan Basin were selected.The Soxhlet extraction and kerogen catalytic HyPy were conducted on the P2d source rocks.The biomarkers obtained by both methods were compared to discuss their difference and the influence extent of thermal maturation on covalently bound biomarkers.The results show that covalently bound biomarkers can hardly be correlated to the corresponding free biomarkers due to severe thermal alterations and/or interference of migrated hydrocarbons in both outcrop sections and thermal maturation have much lower influence on covalently bound biomarkers in kerogens than on free biomarkers in Soxhlet extracts.The application of HyPy in study of biomarker geochemistry can reduce the thermal maturation effect on biomarkers(Ro≤2.4%) to a greater extent and the interference of migrated hydrocarbons between interbedded layers.The covalently bound biomarkers released by HyPy are useful in the study of biomarker geochemistry and oil-source correlation on high-overmature source rocks.
基金Petroleum Technology Development Fund (PTDF), Nigeria for Ph.D scholarship
文摘The compositional and structural changes that coal asphaltenes undergo with increasing thermal maturation were investigated using solid-state13 C NMR and Fourier transform infrared spectroscopy. The results show a gradual increase in the relative proportion of carbon content with a concomitant decrease in the hydrogen, sulphur and oxygen content. The amount of aromatic carbon also increases while the aliphatic carbon decreases with increasing maturity. Ester and carboxylic groups are particularly sensitive to maturation and decrease in relative abundance with increasing maturity while the amount of aromatic carbonyl groups increases. In general, the asphaltenes were observed to evolve towards a more thermally stable structure with increasing amounts of aromatic moieties and relatively lower amounts of aliphatic moieties. The results are in agreement with the ultimate dominance of the island molecular architecture(the Yen–Mullins model) in asphaltenes.
