• 责任者：Wang Shurong (Research Institute of Petroleum Exploration and Production ; SINOPEC ; Beijing 100083 ; China) ; Song Daofu
• 刊名：Acta Petrolei Sinica
• 出版年：2013
• 卷期：34(6)
• 关键词：有机质丰度 ; organic material abundance ; 烃源岩 ; source rocks ; 新疆 ; Xinjiang
• 页码：p.1077-1087
• 图表：9 illus., 2 tables, 30 refs.
• 分类号：1003
• issnNo：ISSN0253-2697
• isbnNo：CN11-2128/TE

     Exploration practice indicates that lots of tuffaceous rocks are good oil source rocks and have a geat generative potential o! hydrocarbons, however, the reason of organic enrichment in tuffaceous rocks remains unclear. Through analyzing petrographical and geochemical characteristics of Carboniferous tuffaceous mudstones in the Santanghu Basin, we investigated the enrichment effect of organic materials by volcanic ash in sediments and found oganic materials highly enriched in Carboniferous tuffaceous mudstones of the Santanghu Basin compared with mudstones of the basin. Volcanic ash was considered as the main factor causing the enrichment of organic materials in tuffaceous mudstones. Hight amounts of mineral bituminous matrix and lamellar algainite, lighter carbon iso- topes of kerogens, concentrated short-middle chain n-alkanes （maximum at nC15 , nC17 or nC19 ） and abundant regular steranes and hopanoids all indicated that organic materials of Carboniferous tuffaceous mudstones in the Santanghu Basin are mainly derived from algae/bacteria. The results showed that the gas and volcanic ash accompanied with volcanic eruption can stimulate algal/bacterial growth through releasing high amounts of nutrient and iron elements to the sea. These algae/bacteria are the main source of organic materials deposited in tuffaceous mudstones and high amounts of algal/baterial materials are the main cause of the organic material enrichment in tuffaceous mudstones. In addition, an evolutionary pattern of tuffaceous source rocks was primarily built up based on previous researches and our new findings.