A STUDY ON THERMAL EVOLUTION OF ORGANIC MATTER IN LOWER TERTIARY SOURCE ROCK OF SUBEI BASIN

Based on many optical and chemical indexes the characteristics and stages of thermal evolution of organic matter in lower Tertiary source rock of Subei Basin were studied in this paper. The following four conclions could be made from the stydies: (1)the vitrinite reflectance (R^o)is the most reliable scale for thermal evolution, (2)With the same fluorescence alternation Sporinite and alginite,are of special importance in thermal evolution, (3)the component and struture of soluble organic matter in source rock changed greatly as the degree of thermal evolution increase, (4)the thermal evolution of organic matter in Subei Basin could be divided into two stages,i. e. stage Ⅰ and stage Ⅱ, which by 0.60%～0.65% R^o,and moreover, the difference of maturity in different tectonic units was showed.