【作者】 许杰；

【导师】 何治亮； 郭建华；

【作者基本信息】 中南大学 ， 矿产普查与勘探， 2009， 博士

【摘要】 塔里木盆地油气资源丰富,具有生油层系多、储集层系多的特点,目前,其基础地质研究已不能满足勘探开发的需要。本文以塔里木盆地上泥盆统一石炭系为研究对象,以经典的层序地层学理论为指导,结合前人研究成果,充分利用塔里木盆地及其周边地区的野外露头资料、地震资料和测钻井资料,运用先进的技术手段和方法,在层序地层学综合研究的基础上,建立了塔里木克拉通拗陷盆地层序地层沉积模式,弄清了层序格架内沉积体系、沉积相分布规律及其演化特征,并对层序格架中生储盖组合进行分析评价,提出了有利的勘探区块。通过地震、露头、钻测井及岩芯相结合的层序地层学综合研究,在盆地范围内,首次拉通了上泥盆统一石炭系层序地层,并将其划分为6个标准的三级层序。其中上泥盆统东河砂岩段为1个完整的三级层序(D3sq),为Ⅰ型层序;石炭系为5个三级层序(Csq1、Csq2、Csq3、Csq4、Csq5),Csq1和Csq4为完整的Ⅰ型三级层序,Csq2和Csq3为Ⅱ型层序,发育海侵体系域和高位体系域,Csq5为Ⅱ型层序,仅发育海侵体系域,高位体系域多被剥蚀。这种三级层序划分方案符合Vail经典层序地层学模式。“东河砂岩”沉积时期其古地理地貌是一个广义的深切谷,呈NEE-SWW向展布,结合盆地周边地层及沉积相分析表明,这是一个向两端开口与海洋连通的大海峡,南、北两侧为古隆起所夹持。“东河砂岩”的沉积环境与沉积岩相变化复杂,并不只是用简单的滨岸沉积可以解释,目前至少可识别出浪控滨岸、潮控滨岸、河口湾(或潮控三角洲)、扇三角洲、陆棚等环境。石炭系沉积体系研究表明,碎屑岩沉积相包括潮坪相、泻湖相、河流相、冲积扇相以及扇三角洲相;碳酸盐沉积相包括蒸发台地、局限台地、开阔台地和台地边缘浅滩。总体来看,海侵体系域主要发育碳酸盐岩沉积,如生屑灰岩段、标准灰岩段和小海子灰岩段均发育在海侵体系域,而高位体系域主要为碎屑潮坪相和扇三角洲沉积,充分反映了海水进退直接影响到碎屑岩与碳酸盐岩的相互消长。平面上东河砂岩段的物性变化较大,塔中地区东河砂岩段的物性明显好于塔北地区,这主要是因为塔北地区东河砂岩段碳酸盐岩胶结严重,直接影响到储层的物性。同一地区东河砂岩段纵向上的物性变化也较大,一般高位体系域发育的储层物性远比海侵体系域储层好,沉积体系对储层的控制作用表现得非常明显。石炭系的储层类型包括碎屑岩储层和碳酸盐岩储层,碎屑岩储层主要分布在巴楚组含砾砂岩段和卡拉沙依组砂泥岩段,同一地区的砂泥岩段物性明显好于含砾砂岩段储层,也就是说扇三角洲储层的物性好于河流相和冲积扇相。碳酸盐岩储层中蒸发台地相沉积的白云岩和灰质云岩、开阔台地相以及台地边缘浅滩相沉积的亮晶颗粒灰岩的物性较好。层序格架内主要有三套大的储盖组合:第一套储盖组合为石炭系砂泥岩段与小海子灰岩段组合,为较好的组合;第二套储盖组合为石炭系生屑灰岩段和中、上泥岩段组合,为较差的组合;第三套储盖组合为石炭系含砾砂岩段、下泥盆统东河砂岩段和下泥岩段组合,为最好的组合。石炭系在Csq2和Csq4层序海侵体系域发育较好的烃源岩,平面上,有两个较好的烃源岩发育带:a、和田1井—玛4井区,b、塔西南西部地区。无论是东河砂岩段和石炭系碎屑岩储层,还是石炭系碳酸盐岩储层,塔中地区塔中18—塔中40—塔中4井区周围都是非常有利的勘探区域,该区储层物性好,圈闭类型多样。巴楚地区西部蒸发台地相云岩沉积区也是有利区块。综合来看,油源和油气运移的通道是塔里木盆地形成大油田的关键因素。更多还原

【Abstract】 The basic geologic research in Tarim basin which is full of abundant hydrocarbon resource and multi oil generative assemblage and reservoir strata now can’t meet the need of exploration and development. Taking Tarim basin upper Devonian - carboniferous as research target and based on classic theory of sequence stratigraphy and predecessor research result, this paper takes advantage of outcrop data, seismic data, drilling data and core data in and around Tarim basin and advanced technical measure and means and establishes sequence strata depositional model of craton basin in the base of sequence stratigraphy comprehensive research and figures out distribution laws and evolution feature of sedimentary system and facies in sequence framework, then analysis and evaluates source -reservoir-cap rock assemblage and propose favorable exploration area.Based on comprehensive sequence stratigraphy research integrated seismic data, outcrop data, drilling-logging data with core data, for the first time ,six standard third order sequences can be identified in upper Devonian and Carboniferous in total Tarim basin. The Donghe sandstone presents one integrated third order sequence （D₃sq）, and the sequence boundary isⅠtype. Five third order sequences can be identified in Carboniferous, which are Csq1, Csq2, Csq3, Csq4-, Csq5. Csq1 and Csq4 are integrated third order sequences that the sequence boundaries areⅠtype. Csq2 and Csq3 areⅡsequence including Transgressive systems tract and Highstand systems tract. Csq5 isⅡtype sequence, which presents Transgressive systems tract only, Highstand systems tract having been erode mostly. The division scheme is correspond with Vail classical sequence stratigraphy models.During deposition of Donghe sandstone, the Paleogeographic physiognomy presents a generalized incised channel which indicates NEE-SWW direction. Integrated with around stratigraphy and sedimentary analysis, this channel is a great strait opening in two ends and connecting with ocean , which is clipped by north and south uplift. The sedimentary environment and lithology facies of Donghe sandstone change very complexly, and the facies can’t be explained by simply shore facies. The facies of Donghe sandstone include wave shore, tidal shore, estuary （or delta controlled by tidal）, fan delta and shelf at least.After study of sedimentary facies of Carboniferous, it can be concluded that clastic facies consisting of tidal facies, lagoon facies, Fluvial facies, alluvial fan facies and fan delta and carbonate facies including evaporation platform, restrict platform, open platform and ford of platform margin. Totally, Transgressive systems tract mainly develop carbonatite deposition, such as bioclastic limestone interval, standard carbonate interval and Xiaohaizi carbonate interval. But Highstand systems tract mainly presents clastic tidal and fan delta. This sedimentary facies distribution model reflects that coming and going of sea water controls the ratio of clastic rock and carbonate rock.The physical property of Donghe sandstone interval changes greatly on plane. The physical property of Donghe sandstone interval in Tazhong area is better than in Tabei area. The reason for those is that the Donghe sandstone interval in Tabei area is cemented by carbonate seriously. Physical property of the same area change greatly vertically too. Reservoir physical property presented in Highstand systems tract is better than in Transgressive systems tract, and controlling of sedimentary system to reservoir presents obviously.The reservoir types of Carboniferous include clastics rock and carbonate rock. Clastic rock reservoir mainly distributes in Pebbled sandstone interval in Bachu formation and Sand shale interval in Kalashayi formation. Physical property of Sand shale interval is better than Pebbled sandstone interval obviously. That is physical property of fan delta is better than fluvial and alluvial fan. The physical property of dolomite and calcareous dolomite deposited in evaporate platform facies and calcsparite grainstone deposited in open platform facies and platform edge ford facies in carbonatite reservoir is better.There are three main associations of reservoir and cap rock in the sequences framework. The first one association is Sand shale interval in Carboniferous and Xiaohaizi calcareous rock which is better one. The second association is bioclastic limestone interval and middle-up mudstone interval which is poor one. The third association is Pebbled sandstone interval, Donghe sandstone interval and down mudstone interval which is better one. Good source rock present in Transgressive systems tract of Csq2 and Csq4, and there are two distributions zones for good source rock. The first one is well Hetian 1-well Ma 4 zone, the second one is the west area of south west Tarim basin.Whether clastic reservoir in Donghe sandstone interval and Carboniferous or carbonate reservoir in Carboniferous, the well area of Tazhongl8-Tazhong40-Tazhong4 are very favorable exploration area. The physical properties of this area are good, and trap types are various. Dolomite deposited in evaporation platform in Bachu area is also favorable reservoir. On the whole, oil source and migration pathway are key factors for development of giant oilfield.更多还原