黔北煤田二叠系煤层含硫特征与沉积环境研究
Study on coal sulfur content features and sedimentary environment of Permian seams in northern Guizhou Coalfield
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摘要: 为了探讨煤中硫特征和沉积环境,采用沉积学、地球化学的理论和方法,对黔北煤田吴家寨背斜二叠系上统龙潭组主采煤层(C12、C8、C5煤层)进行研究。研究结果表明:可将龙潭组划分为3个三级层序,对比各煤层中硫的特征和沉积环境的关系,C12煤层为高硫煤,沉积环境主要为潟湖-潮坪相;C8煤层为低硫煤,沉积环境主要为三角洲平原相;C5煤层为中高硫煤,沉积环境主要为碳酸盐岩台地相。沉积环境对煤中硫起决定性的作用,在三角洲沉积环境中,受海水影响较小,煤中硫含量低,以成煤植物所含的原生硫为主;在潟湖、碳酸盐岩台地环境中,受海水影响较大,煤中硫含量较高,以次生硫的硫化铁硫为主。Abstract: In order to discuss sulfur features and sedimentary environment of coal, the theory and method of sedimentology and geochemistry were applied to stud y on the major mining seams (C12, C8 and C5 seams) of the Upper Permian Longtan Formation of Wujiazhai Anticline in Renhuai, Guizhou Province.The study results s howed that Longtan Formation could be divided into three level sequences and the relationship between the sulfur features and sedimentary environment of each seam were compared.The C12 seam was a high sulfur coal and sedimentary environment mainly was lagoon-tidal flat facies.The Seam C8 was a low sulfur coal and sediment ary environment mainly was the Delta Plain Facies.The Seam C5 was a medium high sulfur coal and the sedimentary environment mainly was the Carbonate Platform F acies.The sedimentary environment would play a decisive role to sulfur content of coal.In the Deltaic sedimentary environment, less influenced by sea water, the sulfur content of coal was low and the primary sulfur content mainly was sulfur content of coal formatted plants.In the environment of Lagoon and Carbonate Platform, highly i nfluenced by sea water, the sulfur content of coal was high and sulfur mainly was iron sulfur of secondary sulfur.