酒西坳陷青西凹陷窟窿山、柳沟庄油藏应属“源岩裂缝油藏”

剖析了酒西坳陷青西生油凹陷中发现青西油田的地质背景，研究了青西油田窟窿山和柳沟庒油藏的形成和分布规律及其控制因素，在此基础上提出了青西油田的窟窿山和柳沟庄油藏属于“源岩裂缝油藏”的新认识。同时论证了“源岩裂缝油藏”形成的特定地质条件和研究价值。提出“源岩裂缝油藏”的特殊意义就在于源岩层中可以找到油藏，其发现和深入研究，将进一步拓宽油气勘探领域，丰富石油地质理论，是一项具有重大科学意义和实用价值的研究课题。     

酒西坳陷构造样式分析

酒西坳陷位于酒泉盆地西端,大地构造位置位于阿尔金走滑断裂带、阿拉善地块与北祁连造山带的结合部位。坳陷边缘断裂祁连山北缘逆冲断裂带和阿尔金走滑断裂带的长期继承性活动及其派生的次级基底断裂控制了坳陷内不同时期的构造格局、构造样式和后期形变(陈建平等,2001),造成坳陷南部中新生界构造层内构造样式多样化。它们的类     

酒西坳陷与酒东坳陷下白垩统生烃条件对比研究

论文通过对酒泉盆地下白垩统各层组烃源岩有机地球化学特征的研究,分凹陷分层组对酒泉盆地下白垩统的生烃条件进行了系统的评价,在此基础上对酒西坳陷和酒东坳陷下白垩统的生烃条件进行了横向对比。研究结果表明,酒西坳陷下白垩统烃源岩的生烃条件从中沟组-下沟组-赤金堡组逐渐变好,而酒东坳陷下白垩统的生烃条件具有从中沟组-下沟组-赤金堡组逐渐变差的趋势,也反映出“好的不熟,熟的不好”的生烃特点。酒西坳陷的下沟组和赤金堡组烃源岩是酒泉盆地下白垩统烃源岩中生烃较大贡献者。研究结果对于本区油气勘探具有重要指导意义。     

酒西坳陷部分原油生物标记物特征异常分析

酒西坳陷大部分原油的生物标记物分布特征较单一,主要表现为三环萜烷、降新藿烷、C30重排藿烷和重排甾烷不发育,伽玛蜡烷相对比较发育,C29甾烷异构化参数较低,一般在0.45~0.5之间,尚未达异构化终点,反映其源岩成熟度并不高。此类原油主要源于青西凹陷下沟组沉积于较强还原环境的藻纹层泥质白云岩。此外,酒西坳陷还发现了部分在生物标记物特征上有别于该区“主体原油”的原油,其表现为三环萜烷、C29Ts、C30重排藿烷和重排甾烷、伽玛蜡烷相对比较发育,而且部分原油(如窿8井、窿4井和窿10井原油)成熟度较高,甾烷C2920S/(20S+20R)值高达0.56~0.58(已达异构化终点),属酒西坳陷成熟度最高的原油,特别是这些原油中绝大部分的C29ββ/(ββ+αα)值也高于“主体原油”,表明其经受了较长距离的运移。根据生物标记物所反映的沉积环境和生源前身物分析以及将其与酒东坳陷主要源于赤金堡组的原油的比较结果,认为在酒西坳陷中,这部分相对于“主体原油”而言的生标特征异常原油可能源于青西凹陷深部的赤金堡组,这一认识对酒泉盆地的深层油气勘探具有实际指导意义。     

乌伦古坳陷未成熟原油的地球化学特征及成因探讨

乌伦古坳陷伦５井侏罗系下统八道湾组油砂具有未成熟在原油的地球化学特征。生物标志物的组成表明，其生源具典型陆源腐殖型有机质或煤系成油特征。油源对比证实，该原油来自下伏三叠系白碱滩组生油岩，形成机制可能为富氢ＩＩＩ型有机质在成油门限以上早期成油。     

辽河坳陷大民屯凹陷古近系沙河街组三段地球化学特征及其地质意义

对辽河坳陷大民屯凹陷沈检5井古近系沙河街组三段(简称沙三段,Es₃)的地球化学特征进行分析,明确大民屯凹陷沙三段的母岩类型、恢复该区的古环境并对构造背景进行判别和讨论,从而确定最终物源。结果显示,大民屯凹陷沙三段的母岩以大陆上地壳的长英质火山岩和太古宙的古老岩石为主,并受到来自幔源的大陆岛弧中基性岩浆影响。A-CN-K、SiO₂-Al₂O₃、Th-Th/U判别图显示源区的化学风化程度较弱。本文根据聚类分析选取出Sr/Cu、Sr/Ba、V/(V+Ni)值等10种元素组合,并根据其纵向分布特征对研究区的古环境进行了恢复。结果显示,Es₃⁴Ⅱ至Es₃³Ⅲ沉积时期,大民屯凹陷的古气候以干热为主并整体呈增强趋势,该区古湖泊的水体盐度低,以弱还原环境为主。研究表明,古气候是控制沙三段元素分配的主因,这与研究区的沉积环境和较为封闭的构造环境有关。稀土元素参数和主微量元素判别图表明,大民屯凹陷同时具有大陆岛弧和被动大陆边缘构造背...     

黄骅坳陷三马地区中-深部储层成岩作用及主控因素分析

黄骅坳陷三马地区储集岩样品的显微特征及成岩矿物的组合关系分析结果表明，三马地区下第三系中深层储层主要处于晚成岩A期，成岩现象包括石英、长石的次生加大、碳酸盐矿物胶结作用、矿物交代作用、溶解作用和粘土矿物转化作用等。其中石英次生加大于2700m左右开始出现，随埋深增大，石英增生加强；长石次生加大现象不十分普遍；碳酸盐胶结作用包括早期自生泥晶方解石胶结作用、连晶方解石和晚期白云石(或铁方解石)的胶结作用。在扫描电镜下可见到方解石与含铁方解石集合体充填在粒间孔隙中或与石英、钠长石及粘土矿物共生，白云岩多呈菱形粒状分布于粒间；常见的交代现象主要有方解石交代长石、石英及粘土矿物，粘土矿物交代长石、石英等；溶解作用主要有长石的溶解、碳酸盐颗粒的溶解和方解石胶结物的溶解等，粘土矿物的转化主要为蒙脱石、高岭石向伊利石(或绿泥石)转化。还讨论了储层岩相、岩性特征、孔隙水中有机酸含量、早期方解石的充填、烃类早期注入等因素对储层成岩演化的控制作用。     

黄骅坳陷北大港复式油气田的形成及富集因素

该文主要论述北大港复式油气田的地质特征，并以断块尧倾活动为主线探讨复式油气聚集带的形成机理。断块体尧倾活动形成丰富的油源区，多期多类型储集砂体与圈闭类型，受多种油气运移方式控制的断块体运移的总趋势，为复式油气聚集带的形成提供优越的生、储、圈等配套条件，有关其形成理论的研究，对复杂断块含油气盆地的油气勘探具有重要意义。     

黄骅坳陷石炭-二叠系凝析油气地球化学特征及来源分析

深层油气勘探是未来油气资源的重要接替领域。渤海湾盆地下伏石炭-二叠系煤系烃源岩自油气勘探取得新突破以来,一直是深层油气领域研究的热点。黄骅坳陷新部署的QG8井奥陶系碳酸盐岩储层和YG1井二叠系砂岩储层获高产凝析油气流,其来源判别问题是深层油气勘探的关键。针对QG8、YG1井凝析油气开展的生物标志化合物、有机碳稳定同位素和原油物性研究表明：两口井的凝析油均为低黏度、低密度的典型轻质原油,具有姥鲛烷优势（Pr/Ph>2.8）,QG8井凝析油饱和烃δ¹³C为-29.1‰、芳烃δ¹³C为-26.8‰;天然气δ¹³C₁偏重,介于-39.7‰~-36.4‰之间,干燥系数大于0.8,重烃可达16.2%,为偏干湿气。QG8与YG1井凝析油特征与黄骅坳陷石炭-二叠系煤系烃源岩（饱和烃δ¹³C为-29.26‰~-26.87‰,芳烃δ¹³C为-26.62‰~-24.15‰）及KG4井原油物性（0.757 1~0.840 2 g/cm³）相近,天然气特征则相似于济阳坳陷GBG1井的煤成气（δ¹³C₁为-43‰~-35‰）,表明高产的凝析油气来自石炭-二叠系煤系烃源岩。证实渤海湾盆地深层石炭-二叠系煤系具有生烃潜力和油气勘探前景。     

黄骅坳陷板桥凹陷沙河街组沙二段物源分析

多年油气勘探表明,黄骅坳陷板桥地区沙河街组具有丰富的油气资源。通过传统分析方法,包括古地貌分析、重矿物特征和砂体分布等资料,对区内沙二段的物源区及其母岩性质、物源方向进行了系统研究表明,板桥凹陷沙二段沉积物主要来自盆地北部燕山构造带和西部沧县隆起,且在盆内发生交互混源,而南部港西凸起物源作用较小。此次物源研究对该区下一步进行沉积相带的划分及储层预测具有重要指导意义。     

酒西盆地青西凹陷下白垩统沉积特征与有利勘探区预测

酒西盆地青西凹陷下白垩统已钻获多口中、高产工业油井,显示具备优越的油气地质条件。受来自西部、北西部、南部、东部4个物源方向控制,青西凹陷下白垩统主要发育扇三角洲、湖泊和湖底扇沉积体系,自盆缘至凹陷中心形成扇三角洲—湖泊—湖底扇展布的二级扇沉积模式。在沉积体系特征分析基础上,结合测井、岩芯及地震资料,对青西凹陷未投入或投入很少勘探工作量的区域进行了有利区块预测,最终确定最有利勘探区2个、有利勘探区3个,并分别进行了详细的区块评价,为进一步滚动勘探提供借鉴和地质依据。     

酒泉盆地青西凹陷下沟组湖相热水沉积岩流体包裹体特征

以地质背景和岩石组构分析为基础,系统研究了酒泉盆地青西凹陷下沟组湖相热水沉积岩中的流体包裹体特征。结果表明,热水沉积岩中的原生流体包裹体以气液二相包裹体为主、单一液相和单一气相包裹体较少、偶见含子矿物三相包裹体。成矿流体属NaCl-H2O型热液体系,温度为90～200℃,盐度为8%～22%NaCl,密度为0.99～1.2g/cm3,成矿压力为15～180MPa。结合锶同位素等地球化学资料分析,认为成矿流体属于深循环的下渗湖水与岩浆水共同构成的中低温、中高盐度和中偏高密度混合热卤水。提出以不同产状的重晶石、铁白云石和萤石为代表的热水沉积岩的成矿热流体系统,自主喷流通道、分支喷流通道经喷流口至附近及远端的盆地热卤水沉积区存在温度、盐度、密度和压力等物理化学参数逐渐降低的分带性变化规律。在热流体特征分析基础上,对研究区早白垩世湖底热流体成矿机制和成因模式进行了探讨。     

酒泉盆地青西凹陷下沟组高分辨率层序分析

主要应用Cross的高分辨率层序地层学理论及其技术方法,对酒西坳陷青西凹陷下沟组进行了层序地层划分,从中划分为2个长期和5个中期数十个短期基准面旋回层序,分析了不同级次的基准面旋回结构、叠加样式、分布模式,及其与储集砂体的发育关系,探讨了地层格架中生、储、盖组合和有利储集相带和铁白云石—钠长石质喷流岩的平面分布规律。     

吉木萨尔凹陷芦草沟组致密油系统的成藏特殊性

通过烃源岩条件、储层特征与原油类型分布及其来源、源-储配置关系的系统分析,分析了准噶尔盆地吉木萨尔凹陷芦草沟组上、下段致密油系统的自生自储与层控成藏特征。结果表明,芦草沟组咸水湖相沉积中的不同岩性均有不同含量的原始有机质,其中的泥岩有机质丰度和生烃潜力最高,为主力烃源岩,母质类型具倾油特征,处于生油阶段。位于烃源岩层系内的砂岩类与碳酸盐岩类储集层主要为低孔低渗-致密背景,含油性与物性差异存在密切关系。源-储配置表现为互层和泥包砂特征,具有源、储邻近叠置分布的致密油聚集条件。芦草沟组上、下段的原油物性与地化特征存在明显差异,分别主要来自邻近层段烃源岩。综合研究认为吉木萨尔凹陷内芦草沟组具有就近运移、自生自储的层控致密油成藏模式。     

青西凹陷下白垩统湖相喷流岩成因探讨及其意义

青西凹陷下白垩统泥云岩 (泥质白云岩、白云质泥岩、白云岩,统称“泥云岩”)以其富含泥级钠长石、石英、铁白云石和重晶石等特殊矿物成分为特点。从构造、沉积、岩石学等方面对青西凹陷下白垩统泥云岩进行了地质分析,指出泥云岩的成因与湖底热水喷流有关。     

银额盆地查干凹陷原油地化特征及油源对比

银额盆地东部查干凹陷首次发现轻质低硫成熟原油，其饱和径含量在90％以上，成熟度相当于镜煤反射率Ro1．0％左右，是生油高峰阶段的产物；原油全碳同位素δ^13C值－31．1‰。原油生物标志物中类异戊二烯含量较高，植烷与姥皖烷均势；三环萜烷含量高于五环萜烷；含有较高的TS C29、Ts、C30重排藿烷、伽马蜡烷；藿烷中以C50藿烷为主，C32以上升藿烷含量极低；孕甾烷含量高；甾烷中以C29甾烷为主，C27甾烷含量也较高，异胆甾烷含量高于胆甾烷；重排甾烷含量低；甾烷的含量与萜烷含量相当，是典型的湖相原油。已发现的天然气中甲烷含量达80％，为湿气。原油和源岩生物标志物组成特征分析对比表明下白垩统巴音戈壁组源岩是主要油源岩。生物标志物特征示原油具有一定的运移效应。     

Formation Models and Distribution of Oil and Gas Pools in Tarim Basin,China

This article reports the main formation models and distribution of the oil and gas pools in Tarim basin,China,including (I) occurrence of the found oil and gas pools,(2) main formation models of oil and gas pools,and (3) distribution law of oil/gas pools.Petroleum is distributed widely in the strata of Tarim basin from the Sinian at the bottom to the Neogene at the top.However,the found oil and gas fields are mainly distributed in Shaya (沙雅) uplift,Tazhong (塔中) uplift,and Kuche (库车)depression.This article presents 4 main formation models,namely,early formation and long-term preservation,early formation and late reformation,middle-late multiphase-multisource formation,late single-stage formation.Tarim basin is very rich in petroleum resources.Long-term inherited intrabasinal paleohighs and slope zones are the most favorable areas for accumulation of hydrocarbons,but the types of oil and gas pools are different from area to area.The control of unconformities and faults on hydrocarbon accumulating is prominent in Tarim basin.Preservation conditions are of utmost importance.Formation of some oil and gas pools is the result of reforming and re-accumulating of early accumulated hydrocarbons.     

Sedimentation of the Lower Cretaceous Xiagou Formation and its response to regional tectonics in the Qingxi Sag,Jiuquan Basin,NW China

Under the constraint of an isochronous sequence stratigraphic framework, sediment infill of the Xiagou Formation reflects the overall control of dynamic tectonic movements and episodic sedimentations in the Qingxi Sag. Structure reactivity during post-depositional processes could cause stratigraphic variations in longitudinal time and lateral space. This study documents sediment infill features and their response to the tectonic evolutions of the Qingxi Sag. The data sets include comparison of cores, well drilling, 3D seismic, inter-well correlation, wave impedance inversion profiles, original strata recovery data, sedimentary facies spatial evolution and their superimposition with paleogeomorphology.The Jiuquan Basin is a Mesozoic-Cenozoic superposition basin comprising an early rifting graben phase and a later compression phase. Since the Early Cretaceous, the basin has undergone four major tectonic episodes: 1) extension during the Early Cretaceous, 2) tectonic inversion caused by northwest-southeast contraction from the Late Cretaceous to the Paleocene, 3) weak extension from the Eocene to the Miocene and 4) contraction from the Miocene to the present. Therefore, the Jiuquan Basin is the product of taphrogenic, collisional and shearing movements.Seismic interpretations of sequence and maximum flooding surface divide the Xiagou Formation into three third order sequences: SQK1g₀, SQK1g₁ and SQK1g₂₊₃. Five sedimentary facies associations are identified: the shoreland plain, fan delta dominated sedimentary systems, turbidite deposits, shallow lakes and half-deep lake systems. From K1g₀ to K1g₂₊₃, decreased sandstone percentages in three fan delta areas indicate a continuously transgressive process, which shows the transition from proximal to distal sites in most statistic wells and an obvious decrease of fan delta scales. The northeast-southwest faults control the lakeward distributions of delta fronts and turbidite fans.The correspondence of sedimentary infill and its response to tectonic movements have been demonstrated in the Qingxi Sag. The more active eastern part of the northeastern boundary fault has an important influence on the northeastward migration of depocenters in the Xiagou Formation. The topography developed continuously from K1g₀ to K1g₂₊₃, but the diminished subsidence indicates the dominant geological process varying from intense fault rifting in an early period to relatively gentle and overall subsidence in a later period during the Early Cretaceous.     

Relationship between Geological Structures and Hydrocarbon Enrichment of Different Depressions in the Bohai Bay Basin

The Bohai Bay Basin contains many depressions with varying degrees of hydrocarbon enrichment associated with the geological structures of different depressions. This study discussed the relationship between the geological structures and hydrocarbon enrichment of the depressions in the Bohai Bay Basin. Based on the Paleogene strata distribution and the length to width ratio of different depressions, their geological structures are divided into three types in plan-view: open(length/width 2), narrow(length/width 4) and transitional types(length/width 2–4). In cross section, the geological structures can be divided into dustpan I, dustpan II and double-faulted types. Based on tectonic evolution and sedimentary characteristics, the depressions are classified into early-formed, inherited and late-formed categories. Generally, narrow depressions are mainly located in the northeast and southwest of the Bohai Bay Basin, while open depressions are dominantly distributed in the central area of the basin; late-formed depressions are mainly around the Bohai sea area, and early-formed depressions are mostly located in the periphery of the basin. Geological structures of the depressions control the formation of the source, reservoir and cap rocks as well as hydrocarbon accumulation setting, and further influence the pay zones and oil-bearing sequence. In detail, dustpan II and doublefaulted depressions mainly have A-type sags, which often possess better hydrocarbon generation conditions than dustpan I ones; hydrocarbons in open dustpan II depressions tend to accumulate in the central uplift areas or buried hill, while those in narrow dustpan I depressions always accumulate in gentle slope belts. The oil-bearing sequence for different evolutional depressions corresponds well with the sedimentary strata of the main development stages of depressions. In early-formed depressions, hydrocarbons are mainly enriched in deeply buried reservoirs, while in late-formed depressions hydrocarbons are abundant in the relatively shallow traps. In summary, most inherited and late-formed dustpan II depressions are enriched in hydrocarbons due to their extensive source rocks and good source–reservoir–seal assemblages, whereas dustpan I and early-formed depressions are relatively poor in hydrocarbons.