鲁西晚古生代海相凝缩层沉积特点及地质意义  

SEDIMENTARY CHARACTERISTICS AND GEOLOGY SIGNIFICANCE OF CONDENSEDSECTION OF NEOPALEOZOIC OF LUXI AREA IN NORTH CHINA

作　　者：吕大炜[1] 李增学[1] 魏久传[1] 刘海燕[1] 宁文峰[1] 

机构地区：[1]山东省沉积成矿作用与沉积矿产重点实验室.山东科技大学,山东青岛266510

出　　处：《西南石油大学学报（自然科学版）》2011年第5期14-20,189,共7页Journal of Southwest Petroleum University(Science & Technology Edition)

基　　金：国家自然科学基金项目(40872100);中国博士后基金(2010471562);山东省自然科学基金(Y2000E07)

摘　　要：依据钻井资料、地层资料及相关地质资料,采用沉积学、层序地层学、煤地质学多学科相结合方法,对鲁西地区晚古生代陆表海沉积进行层序划分,在此基础上分析了不同体系域与凝缩层的关系,探讨了凝缩层与成煤作用的耦合特征,结果表明:鲁西陆表海沉积地层可划分为3个三级层序和24个小层序,每个三级层序由海侵体系域和高位体系域组成。凝缩层主要分布在海侵体系域顶部,即中期基准面旋回顶部,为1个短期基准面旋回,表现为微晶灰岩沉积,局部地区是深水泥岩;该区凝缩层与被动大陆边缘盆地浓缩层有着本质区别,可全区对比;凝缩层与煤层形成具有重要的耦合关系,层序1凝缩层为十四灰和下伏炭质泥岩,层序2的为十灰和16煤,层序3的为三灰和7煤组合,对应煤层的煤化作用开始时间与灰岩形成时间一致,可以用海侵事件成煤模式来解释。By the well log,stratus and other geology information,the relation between system tracts and condensedsection and the characteristics between condensed section and coal-forming are studied in detail based on the depositionalstratus of late Carboniferous epoch-Early Permian of Luxi Area.Three results can be concluded.First,threesequences and 24 parasequences can be divided by the stratus of late Carboniferous epoch-Early Permian of LuxiArea.The depositional systems of condensed section consist of facies of barrier lag,platform lag and so on.Thecondensed section lies on the top of transgressive system tract,which is an upward-deepening short base-level cycleon the top of middle-term cycle.The sediments are mainly pelmicrite and deepwater mudstone,which has a longforming time and a lower rate.So they became a good reference horizon.The condensed section and the forming ofcoal have an important relation.There are essential differences between the condensed section of passive marginalsedimentary basins and epicontinental sea basins.The condensed section of epicontinental sea basins can be foundin the basin.And the depositional sequences in different place are very similar in the same basin.The condensedsections of research area include the fourteenth limestone and carbonaceous mudstone in the 1st sequence,the tenthlimestone and 16th coal in the 2nd sequence,the third limestone and 7th coal in the 3rd sequence.The beginningtime of coalification is the time of maximum sea-level and is in accord with the beginning time of limestone.All ofthese can be explained by the transgressive event of coal-forming.

关 键 词：凝缩层 层序地层 体系域 鲁西地区 海侵事件成煤 

分 类 号：TE132[石油与天然气工程—油气勘探] P539.2[天文地球—古生物学与地层学]