A PETROGRAPHIC CLASSIFICATION OF MACERALS IN TERRESTRIAL HYDROCARBON SOURCE ROCKS IN CHINA AND THEIR ORGANIC PETROLOGICAL CHARACTERISTICS

Having investigated the detailed organic petrological characteristics of more than 300 hydrocarbon source rocks, including oil source rocks, coals and oil shales, sampled from six typical terrestrial oilfields and 15 coalfields in China, the authors sum up the optical properities of the macerals occurring in these source rocks, and investigate their distribution and origins. Three new macerals are recognized which are called as telalginite C, telalginite D and zoo-soft-organisminite.On the base of this, a petrographic classification of macerals in the terrestrial hydrocarbon source rocks of China has been suggested. This system not only displays the organic petroliogical characteristics of our terre strial source orcks sa well as absorbes the strong points of the influenced classifications in the world, but also pays much attention to the following problems at which the organic petrologists haye been working since the past ten years: 1. This system is based on the research of the polished blacks of whole rocks and the thin- sections of Kerogen, and unifies the two classifications and applies the coal petrological maceral nomenclature. 2.The amorphour kerogen is subdivided as detailed as possible in order to make the widest possible combination of the three factors of of gins, optical properties and hydrocarbon-generationg potential of it, and to corresponed it with shaped organic matter in their precursors. 3.The influence of mature level on optical properties of organic matter is stressed in the classification, and an ther classification system for overmature source orcks is presented, and a great effort is made to corrspond it with the maceral in low mature stage accouding to the thermal evolution characters of macerals. Stage accouding as autoanisotropinite, alloanistropinite, micrinite A and micrinte B are suggested to discrible the secondary macerals in overmature stage formed by differeht kinds of hydrogen-rich macerals during theirthermal evolution.