【作者】 李超；

【导师】 申建；

【作者基本信息】 中国矿业大学 ， 矿产普查与勘探， 2018， 硕士

【摘要】 以鄂尔多斯盆地东北缘临兴区块上古生界本溪组~上石盒子组为研究对象,分析了研究区本溪组~上石盒子组沉积环境、层序地层格架和典型层段砂岩发育特征,阐释了煤系砂岩储层特征垂向发育规律及其沉积控制。研究区本溪组~上石盒子组主要发育碳酸盐潮坪、障壁砂坝—泻湖,浅水曲流河三角洲、浅水辫状河三角洲、湖泊5种沉积相,8种亚相以及19种微相。根据二级和三级层序界面,将研究区本溪组~上石盒子组划分出陆表海缓坡盆地边缘型、陆表海缓坡型、陆表海衰亡背景下浅水曲流河三角洲型、缓坡浅水辫状河三角洲型和陆相湖盆浅水曲流河三角洲型等5个二级层序和21个三级层序,并建立了层序地层对比格架。基于层序地层格架,详细解剖了桥头砂岩、山2段砂岩、盒8段砂岩和盒4段砂岩等典型层段储层特征,结果显示四段砂岩各碎屑颗粒阴极发光相似、岩屑含量普遍较高,四段砂岩来自相似的母岩区。四段砂岩石英和长石含量,反映各段砂岩沉积时构造活动强弱所致母源物质的差异,对应于各层序的沉积背景。压实作用是四段典型砂岩储层物性变差的主因,胶结作用使各段砂岩储层进一步致密,溶蚀作用产生的次生孔隙是主要的孔隙类型,其与孔隙结构能较好的对应关系。本溪组~上石盒子组各层段岩性和物性在垂向上呈旋回性的变化,自下而上可分成Ⅰ~Ⅴ五个旋回,受层序格架界面边界关键层、沉积相和成岩作用的控制。第Ⅰ、第Ⅱ、第Ⅴ旋回内不建议合层开发;第Ⅲ、第Ⅳ旋回内可考虑合采。更多还原

【Abstract】 The depositional environment,sequence stratigraphic framework and typical sandstone development characteristics from the Benxi formation to the upper Shihezi formation in Linxing Block of northeastern margin of Ordos Basin are analyzed,and the vertical development regularity and sedimentary control of the characteristics of the coal sandstone reservoir are also explained.5 sedimentary facies,8 subfacies and 19 microfacies are identified from the Benxi formation to the upper Shihezi formation.By identifying sequence boundary and sequence stratigraphic correlation,Benxi to upper Shihezi formation in the study area are divided into 5 two order sequence and 21 three grade sequence,which are the marginal type of the land surface sea gentle slope basin,the land surface sea gentle slope type,the shallow water deltaic delta type,the gentle slope shallow water braided river delta type and shallow water deltaic delta type in continental lake basin.And the sequence stratigraphic framework is established.Based on the sequence stratigraphic framework,the reservoir characteristics of the typical strata in the sandstone of Qiaotou,Shan member 2,He-8 member and He-4 member are dissected in detail.The results show that the four sections of sandstone have similar cathodoluminescence characteristics and high cuttings content.The four sandstone is from the similar parent rock area.The four stage sandstone quartz and feldspar content reflect the distance between source rocks and tectonic activities of sandstone in each section,which corresponds to the sedimentary background of each sequence.Compaction is the main cause of the deterioration of the physical property of the four typical sandstone reservoirs.The cementation makes the sandstone reservoirs in each section further compact,and the secondary pores produced by the dissolution are the main pore types,which can correspond well with the pore structure.The lithology and physical properties from the Benxi formation to the upper Shihezi formation are vertically cyclical,and can be divided into five cycles from bottom to top,which are controlled by the key layers,sedimentary facies and diagenesis at the boundary of the sequence framework.Joint-mining is not considered in the Ⅰ,Ⅱ and Ⅴ cycles,which can be tried in the Ⅲ and Ⅳ cycles更多还原