关于有机质成熟度指标的评述

here are three categories of mature indicators of organic matter in current petroleum industry to evaluate the degree of thermal evolution for source rocks, including: (1) optical indicators, i.e., vitrinite reflectance (Ro), bitumen reflectance (Rb), sporopollen color and thermal alteration index (TAI), conodonts color alteration index (CAI), and reflectance of fossil fragments, such as chitinozoan, graptolite, and scolecodont；(2) chemical indicators, i.e., the maximum temperature in pyrolysis of organic matter (Tmax), methyl phenanthrene indicator (MPI), the atomic ratio of H/C, carbon isotope indicator, and biomarker indicators；(3) indicators of spectroscopy, i.e., the free radical concentration of kerogen, the average structural scale of aromatic nucleus of kerogen, and the laser-Raman spectrum of organic carbon. After comparing the advantages and shortcomings of each indicator, it is pointed out that, the average structural scale of aromatic nucleus of kerogen, and the laser-Raman spectrum of organic carbon are the most effective indicators for evaluating the maturation degree of highly-evolved organic matters, because spectroscopy methods can detect the structural changes of organic carbon directly.