APPLICATION OF PALYNOFACIES TO THE STUDY OF THE PALEOZOIC SOURCE ROCKS IN LOWER YANGTZE REGION

We discussed the origin, organic-matter type and the formation environments of the source rocks occurred in the Lower Cambrian Mufushan Formation and the Lower Permian Chihsia Formation in the lower Yangtze region upon palynofacies. High quality source rocks with high TOC occur in the Mufushan Formation. They were dominated by over 90% of amorphous organic matter in most of the cases, and predominated by the type I of organic matter mainly from aquatic organisms formed in suboxic-anoxic lagoonal or estuarine environments. The organic matters in the Chihsia Formation are also dominated by amorphous organic matters, but with obvious variations in organic components, so it is of a mixed-type. The frequent change in sedimentary environments and oxygen-deficiency level made the source rocks distributed in a heterogeneous manner with lower TOC and lower quality.