【作者】 祝贺；

【导师】 刘家铎；

【作者基本信息】 成都理工大学 ， 沉积学， 2011， 博士

【摘要】 本论文以现代沉积学、层序地层学、石油地质学的理论为指导,以塔里木盆地三叠系为研究对象,系统开展沉积体系、层序地层学及有利区带预测研究,为塔里木盆地三叠系进一步油气勘探提供重要的基础地质资料。论文充分利用盆地内钻井岩心、测井响应及相序组合等标志,塔北-塔中地区三叠系共识别出5类沉积体系和26个沉积微相。重点查明了三叠系发育了辫状河三角洲、扇三角洲和湖底扇沉积体系,并建立了坳陷湖盆缓坡带辫状河三角洲模式、深水湖底扇模式及坳陷湖盆陡坡带扇三角洲模式。以经典层序地层学及陆相层序地层学最新进展为理论基础,在精细沉积体系划分及沉积微相特征研究基础上,综合运用地震、钻测井、岩心和分析化验资料,从层序界面识别入手,对塔北-塔中地区三叠系进行层序地层分析。依据沉积学、古生物学、地球物理及地球化学等标志,共识别出了5个层序界面(SB1-SB5)。层序界面性质主要包括不整合面、超覆面、测井曲线形态突变面、旋回叠加方式转换面、侵蚀冲刷面和岩性、岩相转换面等多种类型,其中以侵蚀冲刷面和岩性、岩相转换面最为普遍。在上述关键界面识别基础上,首次在整个塔北-塔中坳陷内将三叠系划分出4个三级层序(SQ1-SQ4)。各层序发育低位体系域(LST)、湖侵体系域(TST)和高位体系域(HST),有些被削蚀的部位缺少HST,在有些深凹区缺少LST。通过对过渡相带关键井的层序特征分析,结合地震剖面的精确标定,建立了研究区的等时地层格架。研究区东西向层序发育个数可以较好地对比,塔中地区上部层序局部隆升缺失,塔北隆起下部层序沉积缺失。结合层序充填过程及层序发育的主控因素分析,建立了两种层序充填模式:①以塔北-塔中湖盆东部和东南部的斜坡部位为典型代表的缓坡坡折背景的层序充填模式;②以塔北隆后带的斜坡部位为典型代表的陡坡带型层序充填模式。在三级层序(相当于长期旋回)和沉积体系研究基础上,首次采用上升和下降相域作为编图单元对塔北-塔中地区三叠纪进行了层序岩相古地理编图。系统分析了全盆地三叠系各三级层序相域沉积相展布规律与时空演化特征。在上述研究的基础上,系统分析了塔里木盆地三叠系烃源岩、储集岩和盖层的特征,以及在层序格架中的组合类型和特征。塔北-塔中地区三叠系层序格架内发育有4套区域性生储盖组合,进一步划分为自生自储自盖、上生下储上盖和下生中储上盖三种生储盖组合类型,从宏观上控制了塔北-塔中地区三叠系油气的分布。结合塔里木盆地三叠系油气勘探现状,提出了塔北-塔中地区有利的勘探目标。更多还原

【Abstract】 Based on the theory of sedimentology, sequence stratigraphy and petroleum geology, this dissertation take the Triassic strata as the object,systematically research the depositional system, sequence stratigraphy and prediction of favorable block. These achievements would provide important basic information for further petroleum exploration in the basin.Based on the signs of cores, log respons e and combination of phase sequence, the Tabei-Tazhong area identified a total of 5 classes depositional systems and 26 microfacies in the Triassic. Mainly developed the braided delta, fan delta and the sublacustrine fan depositional system. Consequently, the depositional models of the Triassic in the Tarim basin have been established, which Include depression basin gentle slope braided delta model, deep Water sublacustrine fan model and depression basin steep slope fan delta model.On the theoretical basis of classical sequence stratigraphy and nonmarine sequence stratigraphy,s new progression, the analysis of sequence is made in Tabei-Tazhong area from the recognition sequence boundary by use of 3-D seismic, drilling, logging and coring and analysis of laboratory data.Based on sedimentology, palaeontology, geophysics and geochemistry signs, five sequence boundaries were identified (SB1-S B5) . There are several nature of sequence boundaries, including unconformity, onlap-offlap surfaces,mutant form of surface of logging curve,conversion surface of cycles overlapping mode, erosional surfaces and transitional surfaces of different lithologies,which the erosional surfaces and transitional surfaces of different lithologies are most common.According to the key surfaces, it was the first time to divided Triassic into two second-order sequences(SSQ1,SSQ2)and 4 third- order sequences( SQ1-S Q4) in Tabei-Tazhong area.Each sequence developed lowstand systems tract(LST),transgressive systems tract(TST) and highstand systems tract (HST).Some of the cut erosion site is lack of HST and in some morphologic deep areas is lack of LST.Based on the lot of well data to be studied as well as the long sections tied with boreholes to be correlated, and combined with precise calibration of seismic profiles, the regional sequence stratigraphic framework has been established. The number of sequence development can better comparison in East-west study area,the upper part of sequence was missing because of local uplift and Tabei was missing the lower part of sedimentary sequence.The paper combined the filling process sequence with sequence development of the controlling factors and built two types of squence filling patterns in depression basin i.e. gentle slope sequence filling pattern and steep slope sequence filling pattern.In eastern and southeastern parts of the lake is a typical representative of the former.The after uplifted area of Tabei as a typical representative of latter.Based on the third sequence (long-term cycles) and the sedimentary system, It is the first time to choosing the rising and falling base-level phases of each third sequence as the isochronous mapping unit, and carried out thesequence-paleogeography maps of the Triassic in Tabei-Tazhong area. Systematic analysis of the sedimentary facies evolution of time and space law in Tarim Basin All of these,the paper analyzed the space-time configuration rule of reservoir rock in the systems tract, and then study source rock, reservoir rock and cap rock characteristics and the rule of combination development of spatial and temporal distribution. Finally, coupled with exploration fruits and distribution of lithological and stratigraphic traps in the Tabei area, proposed two favorable exploration blocks.更多还原