The Oil-source Correlation, Biological Source And Paleo-climate Studies Of Triassic Source Rocks In Xifeng Area Of East Gansu Province

Chinese petroleum industry is very famous in the world because of the character of continental petroleum. The 90% output of petroleum and over 50% output of natural gas come from terrestrial sediments in China. The reserves of petroleum and natural gas are abundant in China. But as was estimated, the reserves of terrestrial petroleum that had been proved up are only 35% of the theoretic, and the natural gas 12% by the end of 2002. So continental petroleum still has a prosperous lookout. When China discover the new field including deep oil and gas, coal bed gas, gas hydrate and non-biological oil and gas etc, it is still necessary to strengthen the research and exploration of continental oil and gas basins, to exert the potential of the terrestrial oil and gas resources.The theory of continental petroleum generation established by Chinese scientists guided Chinese petroleum industry in the past 40 years. But nowadays the theory need to be perfected by the study on biomarkers, lacustrine algae and paleo-climate concerned about hydrocarbon source rocks. The biomarker research is not only a fundamentally way for oil-source correlation and oil-gas system research, but also very helpful on the study of organic matter biological sources and their paleo-climate. Crude oils are mainly formed from sapropel-type organic matter of low-grade hydrophyte and phytoplankton. So the study of continental algae types and their paleo-climates are very important to help continental petroleum exploration and perfect the Chinese continental petroleum generation theory.Xifeng Oil Field is a big oil field recently found in southwestern Ordos Basin of East Gansu Province, its crude oil sources from Triassic Yanchang Formation are as the same as the earliest explored Yanchang Oil Mine in China. Just based on the study of Yanchang Formation, Professor Pan Zhongxiang brought forward the theory of terrestrial oil generation. The exploitation time of Xifeng oil field is short and the research work is insufficient. The primary problem at present is where the oil source lies in, which confined us from evaluating resources and locating exploration areas. We take Yanchang Formation of Xifeng Oil Field to carry through organic geochemistry of source rocks, biomarker study of oils and source rocks, the relation of oils and sources, micropaleontology of source rocks, in order to confirm dominating oil sources. And...