【作者】 吴仕虎；

【导师】 徐国强；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2011， 硕士

【摘要】 焉耆盆地位于南天山构造带东部,是中、新生代陆相沉积盆地。博湖坳陷是盆地南部中新生代的叠合坳陷,为中生界侏罗系的沉积沉降中心。近年来完成的油气资源评价结果显示,该盆地资源量巨大,勘探程度低。目前,发现的油气田主要为背斜型构造油气藏,找到具有接替意义的非背斜圈闭是现在勘探任务的重中之重。八道湾组岩性圈闭就是有利勘探目标之一,弄清其沉积体系具有重要意义。本论文在吸收前人研究成果基础之上,从焉耆盆地已有的井资料出发,以地震资料为基础,首先开展了15口代表井的合成记录制作及钻井分层地震标定,并对岩相与地震相对应关系进行总结,在此基础之上,对全区二维地震资料进行八道湾组地层(层序界面sb1～sb4)、构造闭合解释,根据工作组利用线描法及层序标准化理论建立的层序地层格架的基础上进行地震相-沉积相对应关系研究,最后,对研究区八道湾组沉积体系综合分析。通过开展上述工作,获得的主要成果与认识有:在工作组建立的层序地层格架内对八道湾组3个层序(SQ1、SQ2、SQ3)开展详尽的地震相-沉积相、沉积体系分析,获得主要认识包括:1)物源:总体分西北、东北和南部物源3个物源区12个物源;2)水流体系和扇-三角洲分布:盆地内主要发育三大水体系,包括:NW→SE水流体系、NE→SW水流体系,S→N水流体系。东北和西北水流体系流经北部凹陷后,末端可以进入南部凹陷,而南部的水流体系,局限于南部凹陷;3)沉积相类型:识别出冲积扇(近岸冲积扇、水下冲积扇)、三角洲(辫状河三角洲、曲流河三角洲和扇三角洲)、浊积扇(三角洲前缘的深水浊积扇和近岸冲积扇前缘的深水浊积砂体)、深湖-滨湖沼泽(可大致区分出深湖-半深湖、滨浅湖、滨岸沼泽)等沉积相类型。4)沉积体系:整体上将盆地侏罗系沉积体系划分为冲积扇-三角洲-浊积扇沉积体系、湖相沉积体系两大类;不同沉积时期、不同地理位置,发育的沉积体系有较大差异;5)相控因素:符合“构造控盆、盆控沉积”的一般规律,区内东西向直压型和北西-南东、北东-南西压扭型三个构造带对物源、水流、沉积相和沉积体系起绝对控制作用;更多还原

【Abstract】 Yanqi Basin locates in the east of the South Tianshan Mountain tectonic structure, which is the Meso-cenozoic sedimentary basin.Bohu is a Meso-Cenozoic overlaying depression in the south basin,which is the Mesozoic Jurassic depositional center. The hydrocarbon resources estimated results finished in the recent years suggest that, the resource of this basin is huge, while the exploration degree is low. The fields found are mainly anticline structure reservoirs at present. The most important of exploration assignment is to find non-anticline traps which replace the old ones. Badaowan formation lithologic trap is one of the most beneficial exploration targets. Thus , it is significant to make clear its sedimentary system.On the basis of previous researches, this paper takes the current well in Yanqi Basin as precondition, the seismic data as basis. Firstly synthetic seismograms and well picks seismic demarcation of 15 representative wells are launched. And then the correspond relationship between lithology and seismic facies is concluded. On the basis above, the Badaowan formation (sequence boundary sb1~sb4) and tectonic close interpretation are launched on 2D seismic data of the whole district. The correspond relationship between seismic facies and sedimentary facies is studied on the basic of sequence statigraphy framework built by line dawing and sequence statigraphy standard theory. Finally, the Badaowan formation sedimentary system in study area is analyzed integrally. Through the above works, the main results and views obtained are as follow:The seismic facies-sedimentary facies and sedimentary system of the 3 sequences in Badaowan formation are analyzed under the sequence statigraphy framework built by our team, and the key view obtained includes:1) provenance: generally divided into northwest, northeast and south 3 provenance area and 12 provenances2) river system and fan- delta distribution: 3 river systems are developed mainly, including NW→SE river system, NE→SW system, and S→N system. The northeast and northwest river systems flow by north depression, and then the end flow into the south depression. While the south river system restrict in the south depression only.3) sedimentary facies types: alluvial fans(offshore alluvial fans and subsea alluvial fans ), delta(braided river delta, meandering river delta and fan delta), turbidite fan( deep-water turbidite fan of delta frontage and deep-water turbidite sand-body of offshore alluvial fan frontage), deep lake-offshore lake swamp( deep lake-semideep lake, offshore lake and offshore swamp can be divided roughly) etc.4) sedimentary system: generally the Jurassic sedimentary in this basin is divided into alluvial fan-delta-turbidite fan sedimentary system and lake facies system 2 styles. The different depositional period and different geographic location, the sedimentary systems developed are various.5) faceis controlled factors: the common rule of tectonic controls basin and basin control deposition is coincided. The east to west vertical pressure and northwest to southeast, northeast to southwest compresso shear, 3 tectonic belt control absolutely provenance, river, sedimentary facies and system.更多还原