【作者】 张翠梅；

【导师】 任建业； 刘晓峰；

【作者基本信息】 中国地质大学 ， 能源地质工程， 2010， 博士

【摘要】 断陷盆地同沉积构造的发育活动和配置样式控制着构造古地貌、沉积过程和沉积相展布等,随着三维地震资料的广泛应用,精细的构造-沉积分析成为了近年来沉积盆地分析研究的热点问题。本文在对大量实际资料进行综合研究分析的基础上,以南堡凹陷的构造发育史、沉积充填史和层序地层格架等研究为基础,选取老爷庙、高柳和蛤坨三个地区解剖同沉积构造样式、形成机制和发育演化,并重点探讨了同沉积构造对沉积物入口、沉积物输送路径、沉积相展布控制以及这些沉积作用在不同构造演化阶段的响应,即分析构造活动对同时期沉积过程的控制和构造演化控制的沉积演化。结合烃源岩和储层展布,预测有利圈闭类型,建立构造—沉积—成藏模式。该研究丰富了中国东部陆相断陷盆地构造—沉积分析理论,同时对南堡凹陷三个典型地区的油气勘探具有一定的指导意义。论文研究取得的主要认识如下：1.厘定了老爷庙地区构造性质,并分析其成因机制根据背斜枢纽与西南庄边界断层的垂直关系,将老爷庙背斜划分为横向背斜,其顶部叠加了走滑断裂,构造主体为断背斜。通过绘制西南庄断层断面等值线图发现,老爷庙段断面上凸,断层倾角最小,剖面上断层在该段底部发生弯曲导致顶部地层挠曲褶皱,厘定了老爷庙横向背斜是由西南庄断层线偏移而形成的横向褶皱,横向背斜的两翼厚,中间薄,为同沉积褶皱,从沙二段沉积时开始发育,到馆陶组活动停止；南堡凹陷受郯庐断裂和张家口—蓬莱走滑断裂的影响,中新世以来NE和NW走滑断裂特别发育,老爷庙地区走滑断裂从区域上属于北堡西—老爷庙NE走滑断裂体系的组成部分,Nm—Q沉积时期形成。2.分析了老爷庙横向背斜对沉积物入口、输送路径和沉积相展布的控制含砾率高值区通常被用来指示古河道的位置。老爷庙地区含砾率统计发现,含砾率最大值位于横向背斜和边界断层交汇处的M40和M36井附近,且顺横向背斜轴向上含砾率值逐渐降低,向两侧向斜含砾率陡降,说明了横向背斜和边界断层交汇控制了水系入口,古河道沿横向背斜轴部展布,横向背斜轴部提供了输砂路径,水系入盆后沿此路径“长距离”输送进入深凹；识别出了同沉积横向背斜的上坡折和下坡折,上坡折位于横向背斜转折端附近,下坡折位于两翼拐点之下。通过井震对比进行沉积相划分,发现扇三角洲平原发育于上坡折间的背斜转折端,扇三角洲前缘发育在翼部上坡折和下坡折之间,浊积扇发育于翼部下坡折和背斜前部倾伏端下坡折之下,说明了横向背斜坡拆控制了沉积相带的展布。古地貌恢复和沉积相平面图显示老爷庙扇三角洲呈舌状展布,长轴平行于背斜枢纽,翼部的沉积相相带分布窄,相变快,背斜轴向上相变缓,向盆内延伸范围广。3.建立了老爷庙构造—沉积—成藏模式结合横向背斜的沉积相展布和前人对该区储层物性的刻画,提出老爷庙地区有利储层扇三角洲前缘的水下分流河道和河口坝主体分布于庙南的横向背斜转折端。走滑断裂切割横向背斜形成的背斜圈闭、断块、断层圈闭,构成了该区最有利的圈闭—构造圈闭。综合构造性质解剖、构造—沉积控制和成藏条件分析,提出老爷庙构造—沉积—成藏模式：背斜控制沉积储层分布,走滑断裂提供油气运移通道,背斜叠加走滑断裂控制了有利含油气圈闭的发育。4.刻画了高柳地区的构造样式；并解剖边界断层的“跷跷板”式活动、演化特征高柳地区受西南庄、柏各庄边界断层和高柳断层限制,保存和记录了Es时期的构造变形,是研究南堡凹陷边界断层特征和成盆机制的“构造金三角形”。重力等值线和水平切片上,西南庄和柏各庄断层没有切割关系,认为西南庄和柏各庄实际为一条断层,即西-柏断层带。该区二级断裂不发育,南部发育“卷心菜”构造、柳赞逆牵引背斜。断层铲状、断层活动性统计、剖面解释和地层厚度统计特征均显示了西-柏断层的西段和柏段构造的差异性。柏各庄断层走向NW,总体倾角大,产状陡,Es1和Ed3时期活动强烈,控制沉积中心位于拾场东次凹的；西南庄断层走向NE,形态呈铲状至板状变化较大,Es3和Es2时期活动强烈,控制沉积中心位于拾场西次凹。据此提出了西-柏断层“跷跷板”式活动模式：Es3和Es2时期西南庄断层活动强烈,柏各庄断层活动微弱,尤其在Es31亚段—Es2沉积时期,西南庄断层强烈活动导致柏各庄下降盘掀斜抬升,遭受剥蚀；Es1界面之上,柏各庄断层活动强烈,,并导致西南庄下降盘的掀斜抬升。总体上,高柳地区的南部表现为斜坡带,北部的沉降中心和掀斜抬升剥蚀交替变化。5.进一步完善了高柳地区的物源体系,划分出陡坡型和缓坡型沉积物堆积样式,并建立了西-柏断层“跷跷板”式活动的沉积响应模式根据录井、测井和地震反射结构,识别出位于G11井附近新的物源区—高西南物源,该物源主要控制和影响了Es1界面之下的西南缓坡带的沉积。将沉积物堆积划分出缓坡型和陡坡型两种堆积样式。前者主要分布在断层掀斜控制的缓坡带,水系长距离推进,流域范围广,沉积相展布面积大；后者主要分布在边界断层陡坡带,沉积物快速堆积卸载,沉积相分布窄。结合沉积物堆积样式,进一步将“跷跷板”活动划分出4个阶段,建立了各活动阶段的沉积响应模式：①早期双断阶段,西-柏断层下降盘均表现为陡坡带近距离卸载堆积；②中期西段陡坡和柏段缓坡阶段,沉积物由柏段缓坡带长距离搬运、大面积分布,西段陡坡快速近距离堆积；③晚期西段缓坡和柏段陡坡阶段,西段沉积物长距离输送进入湖盆深凹,柏段陡坡垂向加积显著；④末期双缓阶段,双向沉积物供给充足,湖盆被大面积充填。6.建立了西-柏断层“跷跷板”活动的控藏模式跷跷板活动晚期引起了早期地层产状的变化,对先期形成的圈闭加以改造并形成新的圈闭。Es1开始沉积前,在柏段缓坡区,发育地层不整合遮挡圈闭、河道砂岩岩性圈闭和扇三角洲前缘砂体前积反方向上形成的砂后上倾尖灭圈闭,在西段洼陷带,发育断层—岩性圈闭和河道砂岩岩性圈闭。Ed沉积后或Ng沉积前,高柳地区结构发生变化,形成柏段陡坡,西段缓坡,使得早期地层或储层产状发生变化,先存圈闭类型被部分改造,如Es1不整合面遮挡形成的不整合圈闭,晚期随西段翘倾,部分转变为砂岩上倾尖灭圈闭；早期柏段缓坡带的扇三角洲前缘砂后上倾尖灭圈闭,晚期沉降旋转,形成砂前上倾尖灭圈闭等。此外,在新沉积的地层内部也发育了大量与缓坡和陡坡背景相关的圈闭。高柳地区南部受缓坡背景控制,早晚期发育了河道砂岩岩性圈闭、砂岩上倾尖灭圈闭、地层超覆圈闭和地层不整合遮挡圈闭。7.识别了蛤坨地区主要同沉积断裂样式和组合,确定了蛤坨地区的古构造格架识别出蛤坨地区主要同沉积断裂—蛤北断裂、蛤坨帚状断裂系统和柏各庄断裂,它们共同限定了蛤坨潜山披覆背斜构造。蛤北断裂新生界开始活动,明显控制了Es3和Es2地层沉积,之后继承性活动,但活动微弱；蛤坨帚状断裂系统主断层在始新世时期开始活动,控制了曹妃甸次凹的形成,渐新世中期开始出现帚状断裂系统的雏形,呈SE收敛、NW撒开的弧形,是左旋张扭应力的产物。蛤坨地区早晚期均表现为“两凹夹一隆”构造格局,但控制性断层不同：Es1界面之下,蛤北断层和柏各庄断层控制柳南次凹沉积,蛤坨断层控制曹妃甸次凹沉积；界面之下,蛤北断层活动微弱,高柳断层开始活动,和柏各庄一起控制柳南次凹的沉积,蛤坨帚状断裂系统控制了曹妃甸次凹的沉积。8.在物源体系判断基础上,分析了蛤坨地区柏各庄断层活动性与沉积物叠加样式之间的关系,提出了蛤坨帚状断裂带的“切帚状断裂走向的输砂模式”根据断层活动性控制的构造沉降速率和沉积物供给速率之间的关系,进一步划分出6种陡坡型沉积物堆积样式：仰进积型、俯进积型、近进积型、远进积型、加积型和上超型,其中前4种是有上升盘物源供给的情况,后2种是无上升盘物源供给；并定性判断出柏各庄断层某点处的活动性强弱。来自于蛤坨东部和北部物源的沉积物在帚状断裂带表现出2种分散特征：切割断裂向低一级断阶输送和顺发散的断阶向下输送,最终形成帚状的扇三角洲前缘砂体分散样式,提出了“切帚状断裂走向”的输砂模式。在此基础上,预测该区有利圈闭主要是与帚状断裂系统相关的圈闭,如断层圈闭、断块圈闭、断层—岩性圈闭等类型,主要分布在帚状断裂系统的断阶内。9.探讨了构造对沉积作用控制的机理和南堡凹陷的形成机制,并总结了盆地演化不同阶段在各个地区表现出的构造-沉积响应。系统分析了构造活动对沉积过程的作用机制—可容空间的变化,指出Es1界面的构造变革运动南堡凹陷构造—沉积产生的重要影响。界面之下盆地呈NW—SE伸展,形成一系列NE向展布的断层(包括西南庄断层)和NE向沉积中心；界面之上,盆地呈NW向走滑伸展,控制NW展布沉积中心,说明南堡凹陷是西南庄断层沿柏各庄断层NW走滑方向上的伸展,首次用“转换伸展终端盆地”模式解释南堡凹陷的形成。总结了南堡凹陷Es1构造变革早晚期的构造坡折带、断层活动性强弱、构造样式和构造古地貌对典型构造带的沉积过程和沉积演化控制的规律。更多还原

【Abstract】 Growth Structures plays an important role on control ancient relief, sedimentary processes and sedimentary facies distribution in rift basin. With the widespread ues of 3D seismic data, recently subtle tectono-sedimentary analysis of sedimentary basins has attracted much attention. Based on the expatiation of the tectonic development and sediment filling history, the sequence stratigraphic framework of the Nanpu sag, this thesis discusses the growth structures pattern, activity, evolution, forming mechanisms of three structural belts (Laoyemiao-LYM, Gaoliu and Getuo) and their controls on sedimentary processes highlighting on sediments entry, transportation pathway, sedimentary facies distribution, and then establish the model of relationship between tectonics activity and sedimentation. Together with the reservoir-cap combination, finally, this paper accesses the favorable traps distribution and presents integrated model of tectonic-sedimentation-hydrocarbon accumulations. The results could not only enrich the theory of tectono-sedimentary analysis of rift basin in eastern China but also be helpful to guide the oil and gas exploration of three belts in the Nanpu sag. The main results in the thesis are as follows:1. The LYM anticline axis trending NW-SE and plunging to the south is perpendicular to the Xi’nanzhuang fault (XNZF), so it is a transverse anticline, which is superimposed by NE trending strike slip faults. On the seismic sections, the XNZF surface curved and deformed the overlaying strata from Eocene to Oligocene, thus the LYM transverse fold is ascribed to non-planar XNZF surface origin, including the anticline formed at the fault surface salient and adjacent synclines at the concave. The strata of ES2 member-Ed formation show significant thickening from the hinge sidewards the synclines, which prove the anticline to be synsedimentary. The Nanpu sag was controlled both by NE Tan-Lu fault and by NW Zhangjiakou-Penglai strike slip faults in the geodynamic situation, since Miocene it has suffered deformation and formed a large number of NE and NW oriented faults. The strike slip faults of LYM region is part of Beipu-LYM faults system, created in the Nm-Q period.2. Gravel content is largely used to localize the ancient river channels. Such statistics of Ed1 and Ed2 members in the LYM region show a high degree of similarity; all maximum lie on the joint of the transverse anticline axis and XNZF, and the high values zone reflecting the ancient river channel basically coincided with the anticline hinge along which the value reduce slower than towards limbs. The fold hinge is thought to provide major sediment transportation pathway for long distances. The drainage in transverse anticlines may enter the basin from highs on the crosscutting of the anticline and border fault, and flow generally along anticline highs. The upper and lower slope breaks of LYM transverse fold are identified on the seismic data, the former lies on the turn of the anticline crest, the later near the limbs inflection. Combined with the analysis of seismic facies, logging, drilling, the upper and lower slope breaks are consistent with the delimits of fan-delta plain and front, fan-delta front and pro-fan delta respectively. Fan-delta plain accumulated on the anticline crest, fan-delta front on the anticline front and the limbs upper part, slumps on syncline and the Linque subsag. It can be proved that the slope breaks constrains sedimentary facies distribution. The sediment transportation with long distance on the anticline hinge result in fan-delta displaying tongue-like geometry with long axis consistent with the anticline hinge.3. Combined with reservoir properties, suitable reservoirs within the delta subaqueous distributary channel and mouth bar are predicted in the fan-delta deposited on the anticline crest. The transverse anticline superimposed by NE trending strike slip faults accounts for the principal trap-structural traps, such as anticlinal, faulted nose, faulted blocks. The LYM tectonic-sedimentation-hydrocarbon accumulation model is presented as followings:the transverse anticline exerted a major influence both on the sedimentary facies distribution of fan-delta and on suitable reservoir distribution; the strike slip faults penetrating into the deep source rocks by connecting with shallow reservoirs provide the major pathway of hydrocarbon migration; the LYM faulted anticline eventually formed abundant traps.4. We described the structural style of Gaoliu region, and concluded a "Seesaw activity" type as well as the evolution features of the boundary faults. Gaoliu region was restricted by the boundary faults of both XNZ and BGZ, as well as the GaoLiu fault, and it recorded the information of structure deformation during Es, which is of great importance to investigate the characteristics of boundary faults and the forming mechanism of Nanpu sag. It was shown from the gravity contour and horizontal slices that there were no cutting relationships between XNZF and BGZF, thus we considered it as a Xi-Bo fault belt. In this region, second-order faults were not developed, but the "cabbage" type structure and the LiuZan reverse drag anticline were identified in the southern part. The characteristics of fault occurrence, the fault activity statistics, the profile interpretation, and the stratigraphic thickness of statistics have showed striking differences between the Xi segment and the Bo segment on the Xi-Bo Fault. The BGZF was NW trending fault with a steep inclination, and it strongly acted during Es1-Ed3, with its controlling deposition center located in east Shichang subsag; the XNZF was a NE fault and displayed a Shovel-shaped to plate-like morphology, and it strongly acted during Es3-Es2, with its controlling deposition center located in west Shichang subsag. According to those features discussed above, we suggested a "Seesaw activity " type for the Xi-Bo Fault:the XNZF strongly acted during ES3-ES2, while the BGZF presented weak "activity, and especially during the sedimentary period of Es31 submember-Es2 member, the XNZF acted so strongly that the hanging wall of BGZF was tilt-lifted and suffered erosion; on top of the Es1 interface, the BGZF, acted strongly, which led the hanging wall of XNZF to be tilt-lifted. In summary, the southern part in Gaoliu region was considered to be a slope belt, while the northern part experienced an alternative variation between a deposition center and a erosion region after tilt-lifting.5. We improved the provenance system of Gaoliu area, classified steep-and ramp-type sediment stacking patterns, and established the sedimentary response model with respect to "seesaw" type of Xi-Bo fault. According to the logging and seismic reflection structure, we identify southwestern source for the new provenance near the well Gll. This source influenced the deposition of southwestern gentle slope area beneath the Es1 interface. The pattern of sediment stacking could be divided into gentle-slope type and steep-slope type. The former is mainly distributed in the gentle-slope zone controlled by tilted fault structure, the drainage covers a long distance and wide range and so is the sedimentary facies; the latter distributed mainly in the boundary of steep fault zone, the sediment accumulated rapidly and the distribution of sedimentary facies is narrow. Combination of the sediment stacking patterns, the "seesaw" activities are classified into four stages and the sedimentary response models of each stage are also established:1) Early double-break stage. The throw side of Xi-Bo fault appears as steep-slope zone short-distance deposition; 2) Middle steep-slope Xi segment and gentle-slope Bo segment stage. The sediments were transported a long distance and distributed in large area in gentle-slope Bo segment, and the sediments were quickly short-distance deposited in steep-slope Xi segment.3) Late gentle-slope Xi segment and steep-slope Bo segment. The sediments were transported through a long distance into the deep lake in Xi segment and the sediments were significantly deposited vertically.4) End double-gentle stage. Two-way sediments were supplied sufficiently, filling the most area of the lake.6. We produced hydrocarbon accumulation models associated with "seesaw" activity of Xi-Bo Fault. By changing the earlier occurrence of stratum, the later activity of "seesaw" reconstructed the earlier traps. Beneath the Es1 interface, stratigraphic unconformity trap, channel sand lithologic trap and updip pinchout trap appears in the BGZF hanging wall, and fault-lithologic trap and channel sand lithologic trap appears in the XNZF hanging wall. During Es1-Ed formation, the variation of Gaoliu region texture leads to the formation of BGZF steep slope and gentle slope and reconstruct the earlier strata and reservoir occurrence up to form new traps. For example, the unconformity traps formed in Es1 partly convert to the updip pinchout traps. Additionally, many new traps were generated in this period. The southern part of Gaoliu district develops typical traps concerning with gentle slope, such as channel sand lithologic trap, updip pinchout trap, stratum overlap traps and stratigraphic unconformity trap.7. We identify the main synsedimentary faults (the Gebei fault, Getuo broom-shaped fault system and BGZF) which restrict buried hill drape anticline. The Gebei faults developed from Cenozoic and controlled ES3-ES2 member; the major fault of the Getuo fault system formed at Eocene and controlled the formation of Caofeidian subsag. The broom structure took shape at middle of the Oligocene. It shows the arc-shaped converging towards SE and diverging towards NW direction, as a product of sinistral transtensional stress field. Getuo district always presented "two sags one arch ", however, it was controlled by different faults. The Gebei fault together with BGZF controlled the Liunan subsag, and Getuo fault controlled the Caofeidian subsag beneath the Esl interface; above the Esl, Gaoliu fault became active and controlled the Liunan subsag combined with Bogezhuang fault, meanwhile, Gebei fault acted weakly and Getuo broom-shaped fault system controlled the Caofeidian subsag.8. The relationships between faults activity and sedimentary alimentation rate has been established. Model of sandbodies transportation with drainage oblique crossing the broom-shaped faults system is proposed. The author classify the following 6 categories of steep-slope type sediments stacking patterns:up-progradation type, down-progradation type, near-progradation type, away-progradation type, aggradation type and onlap type, first four of them are with uplift-block provenance, whereas the rest lack of provenance. What’s more, qualitative analysis of BGZF activity has been given. The drainage coming from estern and northern Getuo buried hill conduct behaviors of 1) cutting cross the broom-shaped fault and feeding the lower terrace; 2) transporting along the fault terrace downwards into the subsag. These lead to the broom-shaped fan delta front sands dispersing pattern and the model of sandbodies transportation with drainage oblique crossing the broom-shaped faults system is proposed. Finally, we predict that the traps related to the broom-shaped faults system, such as fault trap, faulted block trap and fault-lithologic trap are the favorable traps.9. The mechanism by which structure exerts control on sedimentation-accommodation variation has been systematically discussed. Significant influences exerted by the tectonic motion on deposition of Es1 interface have been pointed out. Beneath the Es1 interface, the basin conducted NW-SE extensional and formed a series of NE trending faults and deposition centers. On the interface, the basin conducted NW transtensional and formd the NW trending eastern Shichang subsag and Caofeidian subsag. Caused by XNZF continued extension along shearing direction of the BGZF, Nanpu sag is firstly attributed to transtensional fault-termination basin. The laws of tectonics controls on sedimentation in different evolution stage of Nanpu sag have been concluded in terms of structural slope break, fault activity intensity、structural styles and paleogeomorphology更多还原