济阳坳陷惠民凹陷夏口断裂带的分段性及其成因机制

本文运用丰富的三维地震资料,通过对夏口断裂带几何学特征及其生长过程分析,揭示了其发育演化的分段性和阶段性,并就成因机制进行了探讨。结果表明：夏口断裂带是由NE走向与EW走向交替出现的4个分段连接而成的锯齿状断裂带,受区域地质背景及断裂发育的力学机制控制,其演化过程可划分为4个阶段;孔店组沉积期仅NE向的第一、三（西段）、四段活动,EW向的第二段、第三段的东段尚未开始活动,整个夏口断裂带处于分段独立发育阶段,尚未整体连接;沙四段沉积期随着区域拉张应力开始由NW—SE向近S—N向的转变,先期NE向断层段持续活动,且在侧接带位置形成的转换斜坡上开始发育近EW向断层段,各NE向断层段间发生软连接;沙三段沉积期在近S—N向的强烈拉张作用下,夏口断裂带发生硬连接,不同走向的各分段断层连接成一整体,形成NE向与EW向交替出现的锯齿形断裂带;沙二段到东营组沉积期为走滑改造作用阶段,在夏口断裂带不同位置发育有帚状构造、走滑双重构造,并在断裂带不同的弯曲段走滑派生出局部的拉张或挤压,体现了拉张背景下的走滑叠加效应。夏口断裂带发育演化的时空差异对于该地区沉降中心、物源通道的分布具有重要的控制作用。     

The controls of geomorphology and sediment supply on sequence stratigraphic architecture and sediment partitioning of the lacustrine rift basin in the Es3 of Liuzan area,Nanpu Sag,Bohai Bay Basin,China

An important hydrocarbon reservoir is hosted by the third member of the Shahejie Formation (Es₃) in the Liuzan area, Nanpu Sag, Bohai Bay Basin, China. The Es₃ can be divided into five third-order sequences (from base to top: Sq1, Sq2, Sq3, Sq4 and Sq5). Utilising well logs, cores and high-resolution 3-D seismic data, this study investigates the development characteristics and styles of sediment transport pathways in the steep-slope zone of the lacustrine rift basin. Two styles of sediment transport pathway are identified in the study area, including the faulted trough and fault slope-break zone. The faulted trough is divided into a single faulted trough, synthetic faulted trough and antithetic faulted trough. The fault slope-break zone is composed of synthetic fault slope-break zone and antithetic fault slope-break zone. The fan-delta plain and fan-delta front are recognised in the study area. The different styles of delivery conduits control depositional facies types and the spatial and temporal evolution of fan-delta depositional systems from Sq3 to Sq5. Based on paleo-geomorphological reconstruction, the dispersal pattern of the steep-slope zone system divided into a northern steep-slope system and an eastern steep-slope system is established. In Sq3, the northern steep-slope system develops large-scale mixed sandy–muddy fan-delta deposits derived from the NW. The eastern steep-slope system feeds the medium-scale gravel-rich fan-delta sediments. In Sq4, the large-scale mixed sandy–muddy fan-delta deposits develop from the NNE direction in the northern steep-slope system. The small-scale sand-rich fan-delta sediments are transported from the eastern steep-slope system. In Sq5, the large-scale mixed sand–mud fan-delta deposits are fed by both the northern steep-slope system and eastern steep-slope system. The strata stacking pattern exhibits a seesaw mode in the study area. Based on the analysis of the channel-belt thickness and the fan-scales, the paleogeomorphology of the drainage area in Sq3 and Sq4 and sediment supply in Sq5 alternatively control the sequence stratigraphic architecture and sediment partitioning in the sink area. The model proposed in this study may aid in the prediction of favourable reservoirs and good source–reservoir–seal development in lacustrine rift basin.     

准噶尔盆地阜康凹陷侏罗系烃源岩特征与页岩气勘探潜力分析

页岩油气正在成为中国油气勘探的重要对象之一。准噶尔盆地是中国西部最大的叠合盆地之一,盆地中是否存在页岩油气是能否打开油气勘探新局面的关键问题。本文通过对比其最大的生烃凹陷(阜康凹陷)的侏罗系烃源岩特征与Barnett页岩,来评价准噶尔盆地页岩油气的勘探潜力。阜康凹陷侏罗系烃源岩与Barnett页岩有以下相似性:①烃源岩规模稍大。阜康凹陷侏罗系主要发育八道湾组、三工河组和西山窑组三套泥质烃源岩层,累计厚度(最大950m)大于Barnett页岩;②干酪根类型相当。阜康凹陷干酪根类型在纵向上表现出一定的差异,下部八道湾组以Ⅱ型—Ⅲ型为主,中上部以Ⅲ型为主。③有机质的丰度偏小,但是存在厚层的煤。阜康凹陷有机质丰度分布符合正态分布,主要分布在1.2%~2.5%,与Barnett页岩相比略微偏小。但是从页岩气的角度来看,阜康凹陷发育多层单层厚度5m的煤层,总厚度超过50m,最大单层厚度超过20m,弥补了泥岩丰度不足的缺憾;④烃源岩已经进入中—高成熟阶段。表征烃源岩成熟度的Ro=1.6%,与Barnett页岩相当。上述对比结果表明阜康凹陷具有生成页岩油气的潜力。在此基础上,本文试图通过生烃潜力法的残留烃量评价本区页岩油气的勘探潜力,评价结果表明残留烃的规模为874.6亿吨,展示出阜康凹陷良好的页岩油气勘探潜力。     

Fault growth and main controlling factors in deep area of Gaoyou SagEI北大核心CSCD

Study of fault growth in deep area of the Gaoyou Sag has great significance for the understanding of the structural evolution and hydrocarbon accumulation of the Gaoyou Sag. Based on high-precision 3D seismic data, the displacement-length relationship and throw data of faults are integrated to reconstruct the growth of the boundary fault and secondary faults in the eastern deep area of the Gaoyou Sag and controlling factors of the fault growth are discussed by analyzing the tectonic stress field and numerical simulation. This study revealed that the Zhen 2 boundary fault had six segments which grew independently in the Eocene Dainan Period and subsequently linked into four segments in the Eocene Sanduo Period. The Zhen 2 fault growth included two phases: short rapid lateral lengthening initially in Dainan Period, followed by a longer phase of slip accumulation and linkage of segments in the Sanduo Period. The strike of Zhen 2 fault which is widely and gently undulate kept in step with Zhen1 extensional boundary fault that controlled the structural evolution of the Subei Basin. The structure of Zhen 2 fault tips is contributed to interaction of fault segments. Two segments overlapped and linked with its neighbor by relay zone, otherwise the segments kept away from the fault and linked near the tip of the fault which interacting the growth progress. The secondary faults are linked alternatively by segments of NEE strike and EW strike and the segments of NEE strike are developed initially in the Dainan Period. Numerical simulation demonstrated that the extensional direction in the area of secondary faults is parallel to the extensional direction of the region and barely influenced by the Zhen 2 boundary fault. The orientational change of the tectonic stress field between the Paleocene and Eocene led to the linkage of secondary faults, which means that the segments of NEE strike are developed by pre-existing fabrics of the Paleocene and the segments of EW strike linked the NEE segments later in the Eocene. ©, 2015, Science Press. All right reserved.     

渤中凹陷碳酸盐岩潜山岩溶分带特征与优质储层分布规律研究

渤海湾盆地渤中凹陷西南环古生界深埋碳酸盐岩潜山天然气获得重大突破,钻井揭示古生界气层垂向上显示分段性特征,该区储层主要受岩溶作用的控制,认识研究区岩溶垂向分带特征是预测优质储层和油气分布的关键。文章利用岩心、薄片、电性特征、能谱测井U 值、C、O、Sr 同位素等资料,结合水动力作用的大小、方向,综合分析认为,岩溶储层垂向具有分带性特征,自上而下分为表层风化带、垂直渗流带、水平潜流带和深部缓流带,且其岩电特征与溶蚀作用强差异性控制了储层发育段。研究表明优质储层主要分布于表层风化带、水平潜流带,且分别在不整合面以下20 m 范围内和距不整合面50~200 m,此外在溶蚀作用弱的深部缓流带,白云岩发育区则是潜在优质储层发育带。明确岩溶垂向分带特征及储层发育规律,对下一步碳酸盐岩区油气勘探具有一定的指导意义。     

济阳坳陷深层构造及其对中新生代盆地发育的控制作用

以3D地震资料和钻井资料的解释为基础,通过对济阳坳陷深层进行构造 地层分析和构造解析,系统阐明了中、新生代各期构造运动在研究区的地质表现,确定出收缩构造系统、伸展构造系统和走滑构造系统等多期构造样式;提出印支期逆冲断层系由多条显著向NE或NNE向凸出的弧形展布断裂系组成;识别出代表燕山主期构造运动的不整合界面(Tgm),确定了J3-K1时期断陷盆地的分布格局;认为印支期逆冲断裂系统是控制本区晚中生代和新生代早期盆地发育的重要的控制性先存基底构造。在区域动力学分析的基础上探讨了该盆地复杂的叠合结构和山脉 盆地的转换过程及机制。从盆地研究的角度,揭示了华北东部中、新生代陆内动力学过程,对于研究区油气勘探实践具有重要意义。     

西湖凹陷中央反转带花港组储层成岩演化南北差异及其影响因素分析

东海盆地西湖凹陷花港组砂岩储层作为西湖凹陷的重要勘探目的层,储层非均质性研究至关重要,笔者等基于储层成岩作用和成岩演化分析,明确中央反转带南北差异,进一步分析其差异成因。研究结果表明,北部地区具有更强的压实作用和溶蚀作用,纵向上以3500 m和4000 m为界划分为酸性、酸碱过渡和碱性3个成岩带,经历两期硅质胶结和三期钙质胶结;而南部地区埋深浅、地温低,仅具有两期钙质胶结,纵向上以4000 m为界划分为酸性和碱性两个成岩带;由于北部地区具有更多的岩浆岩母源贡献使得储层抗压实能力较差,遭受压实更强,但烃源岩较强的生烃强度使得储层遭受溶蚀作用更强,因此北部地区花港组储层具有低孔高渗的特征。该研究对优质储层发育研究和甜点预测具有重要意义。     

济阳坳陷车镇凹陷车66块沙三下段精细沉积相分析

根据测井、地震、岩心资料,运用地质综合方法确定济阳坳陷车镇凹陷北部陡坡带砂体成因类型,搞清深水沉积边界。通过岩心观察与描述、地质地震剖面对比以及沉积相平面分布的研究,认为:车66井区沙三下段发育湖底扇、滑塌浊积扇,它们夹持于暗色深水泥岩之中,以内扇沉积为特色,在主水道及水道间堆积了中、细砾岩碎屑流与背景相泥岩。纵向上,沙三下段具有下部富砂、上部富泥的特征;平面上,自北而南由湖底扇内扇碎屑流→中扇颗粒流、浊流变化,沉积相变化具有从近源到远源发展的趋势,表明了物源来自于北部的埕子口凸起。     

断裂复合汇聚脊对新近系油气远距离富集的控制作用 ——以珠江口盆地阳江东凹与恩平凹陷为例

珠江口盆地珠一坳陷北部断阶带在近40年的勘探实践中一直未获商业发现,近年来在阳江东凹与恩平凹陷北部相继获得重大油气发现,且油气具有远源富集特征.本文提出"断裂复合汇聚脊"是该地区新近系油气远源富集的关键控制因素."断裂复合汇聚脊"是受多条断裂切割复杂化的一类汇聚脊,具有4个特征:①汇聚脊三面分别被恩平17洼、恩平21洼...     

南海北缘东部揭阳凹陷的东沙运动:对油气成藏的影响

东沙运动为新近纪中晚期以来发生于南海北缘的一次构造运动,影响范围主要为东沙隆起及其周缘,对油气的晚期成藏具有重要作用.揭阳凹陷位于东沙隆起东侧,东沙运动的响应明显,且具有一定特殊性.基于区域地质背景和三维地震资料,对东沙运动在揭阳凹陷的响应、起因及油气地质意义进行了论述.东沙运动在揭阳凹陷的响应主要包括走滑断层和地层角...