关键词: 热模拟, 烷烃, 参数, 地球化学特征

Abstract: With a view to finding out the characteristics of alkane generation during the thermal evolution of kerogen,alkanes generated by kerogen in lignite and by total organic matter(kerogen and EOM) of lignite are studied through two series of pyrolytic simulation experiments.The results show that kerogen can't be directly degraded into light oil,and that alkanes in the products from kerogen degradation do not show any odd or even preference,and that the pristane to phytane ratio is relatively high and does not vary sharply with variation of temperature,and that the pristane to nC₁₇ and phytane to nC₁₈ ratios decrease linearly with the increase of temperature.In the products from the thermal degradation of total organic matter of lignite,there is light oil generated; alkanes generated during the lower temperature stage show quite strong odd and even preference;the pristane to phytane ratio becomes first larger and then smaller while temperature is rising;and the pristane to nC₁₇ and phytane to nC₁₈ ratios rise up and drop down repeatedly following the rise of teniperature.

Key words: pyrolytic simulation, alkane parameters, geochemieal, characteristics