层序古地理背景下河南省二_1煤聚集规律研究

Coal Accumulation Pattern of Coal Seam Ⅱ1 under Sequence Paleogeographic Setting in Henan Province

对河南省晚石炭世-早二叠世含煤岩系(太原组中部碎屑岩段、上部灰岩段和山西组二1煤层段、大占砂岩段)进行层序分析,共识别出以胡石砂岩底面、二1煤底面、大占砂岩底面和香炭砂岩底面为代表的4个层序界面,将该层段含煤岩系划分为3个三级层序。通过对层序S1和层序S3岩相古地理图和二1煤厚度等值线图耦合分析发现,障壁岛-潟湖沉积环境为二1煤的聚集提供一个较好的前期环境,分流间湾沉积环境为二1煤的保存提供一个较好的后期环境,而分流河道对二1煤的保存起到了破坏性的作用。

Based on sequential analysis of the Permo-Carboniferous coal-bearing strata （middle clastic rocks, upper limestone members of the Taiyuan Formation and coal seam II1, Dazhan sandstone members of the Shanxi Formation） has identified 4 sequence boundaries represented by bottom boundaries of Hushi sandstone, coal II1, Dazhan sandstone and Xiangtan sandstone, partitioned the coal-bearing strata into 3 3rd order sequences. Through the coupled analyses of lithofacies-paleogeographical map and coal II1 thickness isogram of sequences S1 and $3 have found that the barrier island-lagoon sedimentary environment has provided a better antecedent environment for the accumulation of coal II1 and the interdistributary bay sedimentary environment provided a better succeeding environment for the preservation of coal II1, while the distributary channels can destroy the coal II1.