【作者】 高迪；

【导师】 邵龙义；

【作者基本信息】 中国矿业大学（北京） ， 矿物学岩石学矿床学， 2010， 博士

【摘要】 利用露头剖面、钻井岩心、测井、地震、地化等资料,对泛三江盆地早白垩世含煤岩系进行了沉积学、层序地层学和聚煤作用研究。研究区主要含煤地层为城子河组和穆棱组,城子河组主要发育粉砂岩、细砂岩、泥岩和煤层；穆棱组主要发育泥岩、粉砂岩、细砂岩、中砂岩和薄煤层。识别出冲积扇、辫状河、曲流河、三角洲、湖泊等5种沉积相,其中上、下三角洲平原过渡带是最有利的聚煤环境。共识别出区域不整合面、河流下切冲刷面、沉积相转换面3种类型共5个层序界面,划分4个三级层序,分别对应于SⅢ1—SⅢ4,以层序SIII2聚煤作用最好,在每一层序中,以湖侵体系域聚煤作用最好,其次为低位体系域。古地理分析表明含煤岩系沉积期优势相为三角洲平原,物源主要来自于西南、西北、东北三个方向。总结出陆相断陷盆地的聚煤模式,并分析了聚煤作用与其主要影响因素之间的关系。此外本文还预测了研究区页岩气储量和页岩气勘探有利区域。更多还原

【Abstract】 Early Cretaceous coal measures in the Pan-Sanjiang Basin have been studied using coal-accumulation models, sedimentology, and sequence stratigraphy applied to outcrop, borehole, well log, seismic and geochemical data. Within the research area the main coal-bearing strata are the Chengzihe and Muling formations. Siltstones, fine sandstones, mudstones and coals dominate the Chengzihe Formation, while the Muling Formations is dominated by mudstones, siltstones, and fine to medium grained sandstones. Five sedimentary facies are identified:alluvial fan, braided river, meandering river, delta and lacustrine. The main coal-accumulating environment occurs at the transition between upper and lower delta plain facies. Based on the evolution of the sedimentary environment, characteristics of sequence boundaries and wavelet transformation on gamma-ray logs (GR), five sequence boundaries are recognized. These sequence boundaries include regional unconformities, erosion surfaces resulting from river incision, and reverse surfaces. The sequence boundaries have been used to subdivide the Early Cretaceous coal measures into four third-order sequences. The main coals initially formed under lowstand system tracts and early transgressive system tracts but subsequently developed under middle and late transgressive system tracts and maximum lake flooding surfaces. SⅢ2 is identified as the sequence most favourable to coal accumulation. Palaeogeographic lithofacies analyses indicate delta plain facies are predominant. These facies have source directions from the southwest, northwest and northeast with water invasion from the east. Collectively these data have been used to generate a coal-accumulating model for the inland fault basin and should provide a powerful tool for future coal resource exploration. Besides, reserves of shale gas and favorable exploration zones were predicted in the study area.更多还原