【作者】 郑秀娟；

【导师】 汤达祯； 于兴河；

【作者基本信息】 中国地质大学（北京） ， 矿产普查与勘探， 2005， 博士

【摘要】 塔里木盆地是我国陆上最大的含油气沉积盆地,面积达56 万km2,同时也是当前“开发西部”、“西气东输”的主战场。由于该盆地在不同地质时期的构造格局变化巨大,抬升沉降频繁,早张晚挤,从而形成了现今的叠合盆地。要寻找和掌握该区的不同地质规律,就不得不系统地分析与研究其构造、沉积与充填的演化,因此,论文以塔东北为研究区开展下古生界层序地层格架与沉积相、沉积充填模式研究。采用由点到线、由线到面、再到域的研究思路,充分利用野外露头、岩心、测井及大量的地震资料,以层序地层学、地震地层学和沉积学为理论指导,以层序划分为基础,以测井相和地震相研究为重点、沉积相分析和盆地充填特征为主线,采用新理论和新技术,做到了点、面、井、震、室内与野外的有机结合,系统地构建了该区下古生界的层序地层格架、沉积相展布特征及构造—沉积一体化模式,再现了沉积充填及展布的相互关系,为该区后续的油气勘探提供了理论基础与模式。其核心内容如下: (1)雅尔当山、却尔却克山和元宝山三个下古生界野外露头的详细考察结果表明:寒武纪—早奥陶世主要为半深海沉积环境,岩性主要为灰岩和泥质灰岩。中上奥陶统以半深海相的浊流沉积为主,岩性主要为碎屑岩。志留系沉积以滨浅海的中细砂岩、粉砂岩及泥质粉砂岩为主。进而总结得出本区的三个沉积序列模式:浊积序列、三角洲序列和潮坪序列。(2)下古生界发育2 个Ⅰ级层序,4 个Ⅱ级层序和14 个Ⅲ级层序。Ⅰ、Ⅱ级层序界面均为明显的区域性不整合面,全区分布;Ⅲ级层序界面多为局部不整合或整合界面,不整合局域分布为主。层序界面可归纳为4 种类型:造山侵蚀不整合层序界面、隆升侵蚀不整合界面、海侵上超不整合界面和沉积间断不整合界面,并分析了每一种界面的成因及特征。(3)识别出该地区存在4 种地震相、7 种地震亚相,以地震相解释的界面、形态与属性三者为一体的原则,结合研究区的具体情况,给出了每个层系地震相与沉积相转换的综合成果,从地震角度为沉积相的进一步展开研究提供了依据。(4)寒武系—下奥陶统发育碳酸盐岩台地相和半深海盆地相;中上奥陶统大部分区域为一套浊流沉积,只有西北地区继承了寒武—下奥陶的碳酸盐台地相;志留纪系主要为滨浅海环境,是一套扇三角洲相和潮坪—沼泽相沉积物。(5)首次建立了塔里木盆地东北地区下古生界三个层系的构造—沉积一体化理论模式,从演化的角度再现了研究区沉积体系的展布。更多还原

【Abstract】 Tarim Basin, as the biggest onshore petroliferous sedimentary basin in China, with an area of 560×103 km2, is very important in the development of western China. The structural patterns of Tarim Basin varied a lot in different geological stages. The frequent uplift and subsidence in the stress field of early pullapart and later extraction resulted in the congruence basin of nowadays. Therefore, it’s necessary to systematically analyze the evolvement of structure, deposition and infill to find out the geological rules of Tarim Basin. This thesis studied the sequence stratigraphy frame of the lower Paleozoic group in the northeast of Tarim. On the basis of outcrops, cores, logs and seismic data, under the guidance of sequence stratigraphy, sedimentology and seismic stratigraphy, after building up the of sequence stratigraphy frame, the log facies and the seismic facies were studied in details, and then the deposition and infill pattern were analyzed to work out the distribution of sedimentary facies and the pattern of structural –deposition, which revived the infill and the deposition characters. The result of the thesis provided theoretical basis and pattern for future petroleum exploration in this area. The core of this thesis included the following contents: (1) The investigation of three outcrops in Yaerdang Mountain, Queerqueke Mountain and Yuanbao Mountain showed that, the studied area was in bathyal sea in Cambrian period. The middle and upper Ordovician was characterized by clastic rock of turbidity facies in bathyal sea. The Silurian was mainly medium sand, fine sand, siltstone and pelitic siltstone in shallow sea. Three sedimentary sequences can be concluded from the outcrops, turbidity sedimentary sequence, delta sedimentary sequence and tide flat sedimentary sequence. (2) There are two I level sequences, four II level sequences and 14 III level sequences in lower Palaeozoic group. The I level and II level sequence boundaries are obvious territorial unconformity surfaces; the III level sequence boundaries are partial unconformity surfaces or conformities. The sequence boundaries can be divided into 4 types: orogenesis and erosion unconformity, uplift and erosion unconformity, marine transgression and onlap unconformity, and onshore exposure unconformity. The characters and genesis of every type were analyzed in the thesis.更多还原