Light hydrocarbons, especially C-7 isoalkanes, cyclopentanes, cyclohexanes and n-heptane in 540 oils from the Tarim Basin were studied systematically. The results suggested the K-1 values [(2-MH+2,3-DMP)/(3-MH+2,4-DMP...Light hydrocarbons, especially C-7 isoalkanes, cyclopentanes, cyclohexanes and n-heptane in 540 oils from the Tarim Basin were studied systematically. The results suggested the K-1 values [(2-MH+2,3-DMP)/(3-MH+2,4-DMP)] of crude oils vary from a lowest value of {0.78}, to a highest value of {1.54}, but the K-1 values of the majority of oil samples (80%) range from {0.90} to {1.20}. However, the absolute contents of (2-methylhexane+ 2,3-dimethylpentane) and (3-methylhexane+2,4-dimethylpentane) in the total light hydrocarbons (C-4-C-7) show a similar variation trend. The variation of K-1 values of crude oils can suggest a typical sedimentary environment for source rocks. Therefore, according to the compositional characteristics of C-7 light hydrocarbons in light of the steady-state catalytic hypothesis, non-marine oils from the Yingmaili area and marine oils from the Tazhong uplift in the Tarim Basin were genetically classified.展开更多
Different types of crude oils have different light hydrocarbon compositional and geochemical character-istics. Based on the light hydrocarbon data from two kinds of oils,i.e.,coal-generated oils and marine oils in Chi...Different types of crude oils have different light hydrocarbon compositional and geochemical character-istics. Based on the light hydrocarbon data from two kinds of oils,i.e.,coal-generated oils and marine oils in China,light hydrocarbons in marine oils in the Tazhong area are generally relatively enriched in n-heptane,and coal-generated oils from the Turpan Basin are enriched in methylcyclohexane . The K1 values,reported by Mango (1987),range from 0.97 to 1.19 in marine oils,basically consistent with what was reported by Mango on light hy-drocarbons in terms of the majority of the crude oil data. But the K1 values of coal-generated oils are particularly high (1.35-1.66) and far greater than those of marine oils; heptane values in marine oils,ranging from 32.3% to 45.4%,and isoheptane values,ranging from 1.9 to 3.7,are respectively higher than those of coal-generated oils,in-dicating that the oils are in the high-maturity stage. In addition,expulsion temperatures of coal-generated oils from the Turpan Basin are obviously lower than those of marine oils from the Tazhong area.展开更多
文摘Light hydrocarbons, especially C-7 isoalkanes, cyclopentanes, cyclohexanes and n-heptane in 540 oils from the Tarim Basin were studied systematically. The results suggested the K-1 values [(2-MH+2,3-DMP)/(3-MH+2,4-DMP)] of crude oils vary from a lowest value of {0.78}, to a highest value of {1.54}, but the K-1 values of the majority of oil samples (80%) range from {0.90} to {1.20}. However, the absolute contents of (2-methylhexane+ 2,3-dimethylpentane) and (3-methylhexane+2,4-dimethylpentane) in the total light hydrocarbons (C-4-C-7) show a similar variation trend. The variation of K-1 values of crude oils can suggest a typical sedimentary environment for source rocks. Therefore, according to the compositional characteristics of C-7 light hydrocarbons in light of the steady-state catalytic hypothesis, non-marine oils from the Yingmaili area and marine oils from the Tazhong uplift in the Tarim Basin were genetically classified.
基金financially supported by the National Natural Science Foundation of China (Grant No.40573030)
文摘Different types of crude oils have different light hydrocarbon compositional and geochemical character-istics. Based on the light hydrocarbon data from two kinds of oils,i.e.,coal-generated oils and marine oils in China,light hydrocarbons in marine oils in the Tazhong area are generally relatively enriched in n-heptane,and coal-generated oils from the Turpan Basin are enriched in methylcyclohexane . The K1 values,reported by Mango (1987),range from 0.97 to 1.19 in marine oils,basically consistent with what was reported by Mango on light hy-drocarbons in terms of the majority of the crude oil data. But the K1 values of coal-generated oils are particularly high (1.35-1.66) and far greater than those of marine oils; heptane values in marine oils,ranging from 32.3% to 45.4%,and isoheptane values,ranging from 1.9 to 3.7,are respectively higher than those of coal-generated oils,in-dicating that the oils are in the high-maturity stage. In addition,expulsion temperatures of coal-generated oils from the Turpan Basin are obviously lower than those of marine oils from the Tazhong area.
