HYDROCARBON-FORMING ORGANISMS IN EXCELLENT MARINE SOURCE ROCKS IN SOUTH CHINA

Based on previous studies,excellent marine source rocks in South China were collected and studied by Scanning Electron Microscope and Energy Dispersive Spectrometer.Compositions,hydrocarbon-forming organisms,sedimentary environments and hydrocarbon potential of the excellent marine source rocks were discussed.There are three types of hydrocarbon-forming organisms in the excellent marine source rocks: 1) Pelagic algae,including siliceous Mallomonas,Acritarchs(siliceous Leiosphaeridia,Diatom,Micrhystridium and so on),Cyanophyta(calcareous Chroococcus and so on),and calcareous Tasmanaceae.2) Benthic organisms,including siliceous or baritic or ferruginous algal mats,siliceous sporangium,siliceous filaments relic,siliceous sponge,and original Nematothallus(containing clay).3) Fungi,including calcareous fungi hypha(containing organic matter),calcareous bacteria(containing organic matter),sulfur bacteria(not always containing organic matter),iron bacteria(containing organic matter),calcareous nanobacteria,and so on.Palaeoenvironment was analyzed according the elements and hydrocarbon-forming organisms compositions.Modern algae hydrous pyrolysis in closed system and pyrogenation of oil shales which contain single hydrocarbon-forming organism were carried out.Hydrocarbon potential of pelagic algae was equivalent to type Ⅰ kerogen,and the benthic algae was equivalent to type Ⅱ kerogen.