摘要
为了建立华北地台晚石炭世-早二叠世层序地层格架,绘制相应的岩相古地理图,找出华北地台聚煤作用控制因素,通过对野外露头及钻孔剖面资料分析等工作,将华北地台晚石炭世-早二叠世含煤地层划分为7个三级层序,煤层主要发育在SⅢ3和SⅢ5层序。利用单因素分析多因素综合作图法恢复了各层序中岩相古地理,并对煤层分布规律进行分析,结果表明:SⅢ3层序中煤层发育受到沉积相南北分异、东西展布特征的控制,华北地台北缘以河流泛滥盆地沉积为主,煤层层数少但单煤层厚度大,南缘以碳酸盐台地沉积为主,煤层层数众多但单煤层厚度小,SⅢ3层序的聚煤中心主要位于华北地台北部地区;SⅢ5层序中煤层受到沉积相和基底沉降速率的双重控制,碎屑沉积不活跃沉积相带有利于成煤,30~40 m的层序地层厚度地区有利于成煤,SⅢ5的聚煤中心主要位于河南、京津冀和银川附近地区。
In order to establish the sequence stratigraphic framework of late Carboniferous-early Permian in North China Platform,draw corresponding lithofacies palaeogeography map,and find out controlling factors of coal accumulation,after analyzing data from outcrop section and borehole cores,the strata in late Carboniferous and early Permian were subdivided into seven third-order sequences. Coal seams were located in Sequence SⅢ3 and SⅢ5. The single factor analysis and multifactor comprehensive mapping method was used to reconstruct the lithofacies palaeogeography of each third sequence,and coal accumulating law was analyzed.The development of Sequence SⅢ3coal seam was controlled by the sedimentary facies which presented obvious difference in NS direction and extended in WE direction. In the northern margin of North China Platform which presented as flood basin,a small number of thick coalseams were developed. In the southern margin which presented as carbonate platform,a large number of thin coalseams were developed. Coal-rich zone of Sequence SⅢ3 was located in northern part.in North China Platform The development of SⅢ5 coal seam was controlled by the sedimentary facies and base settlement rate,thick coalseams were developed in inactive clastic sedimentary area which had 30 ~ 40 formation thickness. Coal rich zone of Sequence SⅢ5 was located in Henan,Beijing-Tianjin-Hebei,Yinchuan and its vicinity.
出处
《煤炭科学技术》
CAS
北大核心
2017年第9期175-181,187,共8页
Coal Science and Technology
关键词
华北地台
晚石炭世
早二叠世
聚煤规律
North China Platform
late Carboniferous
early Permian
coal accumulating law
