Application of single cold trap pyrolysis chromatography in source rock evaluation

By means of single cold trap pyrolysis chromatography,the pyrolysis analyses of source rock samples have been carried out.Combining electromagnetic cutting with cold trap enrichment,the hydrocarbon components of source rock during different mature stages have been analyzed with pyrolysis chromatography,and gaseous hydrocarbon has been separated well,providing technical supports for dynamic studies of source rock components.As to different types of source rock,from type Ⅰto Ⅲ of organic matter,the yielding rate of methane increases rapidly while the yielding rates of light and black oils decrease gradually,and the yielding rate of wet gas does not change obviously no matter which organic types it belongs to.The n-alkanes/n-alkenes ratios of pyrolysis product of source rock are controlled by pyrolysis rate,source rock evolution stage and type,hence the ratio can not be used to judge organic matter type.The dynamic analyses of hydrocarbon pyrolysis component in source rock provide data including C₁(dry gas),C₂-C₄(wet gas),C₅-C₁4(light oil) and C₁₅₊(black oil),offering important parameters for source rock quantitative evaluation,oil and gas major generation stage determination as well as the calculation of oil/gas ratio and total resource.