Connotation,pathway and significance of carbon neutrality“super energy system”:A case study of the Ordos Basin,NW China

Super oil and gas basins provide the energy foundation for social progress and human development.In the context of climate change and carbon peak and carbon neutrality goals,constructing an integrated energy and carbon neutrality system that balances energy production and carbon reduction becomes crucial for the transformation of such basins.Under the framework of a green and intelligent energy system primarily based on“four news”,new energy,new electricity,new energy storage,and new intelligence,integrating a“super energy system”composed of a huge amount of underground resources of coal,oil,gas and heat highly overlapping with abundant wind and solar energy resources above ground,and a regional intelligent energy consumption system with coordinated development and utilization of fossil energy and new energy,with a carbon neutrality system centered around carbon cycling is essential.This paper aims to select the traditional oil and gas basins as“super energy basins”with the conditions to build world-class energy production and demonstration bases for carbon neutrality.The Ordos Basin has unique regional advantages,including abundant fossil fuel and new energy resources,as well as matching CO_(2)sources and sinks,position it as a carbon neutrality“super energy basin”which explores the path of transformation of traditional oil and gas basins.Under the integrated development concept and mode of“coal+oil+gas+new energy+carbon capture,utilization and storage(CCUS)/carbon capture and storage(CCS)”,the carbon neutrality in super energy basin is basically achieved,which enhance energy supply and contribute to the carbon peak and carbon neutrality goals,establish a modern energy industry and promote regional green and sustainable development.The pioneering construction of the world-class carbon neutrality“super energy system”demonstration basin in China represented by the Ordos Basin will reshape the new concept and new mode of exploration and development of super energy basins,which is of great significance to the global energy revolution under carbon neutrality.

World's Energy Transition and Chinese-style Modern Energy Revolution under Carbon Neutrality(Ⅰ)

Under global consensus on carbon neutrality and the intensification of regional conflicts,new energy has become the primary direction for various countries to achieve energy security and green development.Represented by wind,solar,geothermal,hydrogen and stored energy,and controllable nuclear fusion,the technological and scale advantages of new energy are being continuously strengthened.Low-cost wind,solar,and stored energy will support the global energy transition.The production and utilization of new energy enter a rapid development phase.In 2022,the average global consumption of new energy accounted for 18.2%,and it is expected to reach around 55%by 2050.The distribution of the world's energy resources,consumption regions,technological development,per capita consumption,energy-saving fields,and carbon emissions is uneven.The acceleration of low-carbon development in fossil fuels,the scale-up of renewable energy,and the intelligentization of energy management drives the rapid transition of global energy.

World’s Energy Transition and Chinese-style Modern Energy Revolution under Carbon Neutrality (Ⅱ)

Chinese-style modernization emphasizes the harmonious coexistence of man and nature and actively yet prudently promotes carbon peak and carbon neutrality.It delves deeply into the energy revolution,upholding the following principles:the“independence”of energy production,the“green”energy supply,the“security”of energy reserves,the“efficiency”of energy consumption,the“intelligence”of energy management,and the“economy”of energy costs.Efforts are being made to accelerate the planning and construction of a new type of energy system that is green and smart,with new energy,new electricity,new stored energy,and new smart energy as the mainstays,to ensure energy security.Currently,China is an energy power but not an energy superpower,and its energy consumption structure still needs further optimization.China’s new energy security strategy is composed of energy consumption revolution,energy supply revolution,energy technology revolution,and energy system revolution,complemented by comprehensive strengthening of international cooperation.This approach is aimed at advancing China’s energy revolution and transforming the nation’s energy supply pattern and shifting from a consumption mix in 2022.

卫星运输T型钢丝绳隔振器刚度及阻尼研究

钢丝绳隔振器可以缓解卫星运输过程中振动产生的危害,但其缺少试验基础研究,无法提供仿真输入,难以准确实现卫星损伤仿真。针对此问题,对T型钢丝绳隔振器刚度及阻尼特性进行了理论分析和试验研究。首先,对钢丝绳隔振器系统的力学特性进行了理论分析,建立了理想的迟滞回环曲线;其次,建立了钢丝绳隔振器静刚度和动刚度力学测试系统;最后,通过准静态加载以构建静刚度条件下压缩、横滚、剪切状态力和位移的关系。在预承载力为5 kN、振幅为1 mm条件下,分别测试了激振频率5~8 Hz条件下的动刚度性能。结果表明:准静态加载条件下,钢丝绳隔振器的力和位移关系较为稳定;动刚度条件下,在5~8 Hz频率之间,动刚度变化较为稳定;等效阻尼随着激振频率的增加而增加。

碳中和背景下世界能源转型与中国式现代化能源革命

全球碳中和共识与地区冲突加剧的背景下,新能源已成为各个国家实现能源安全和绿色发展的主要方向。以风能、光能、地热能、氢能、储能、可控核聚变等为代表的新能源技术和规模优势正在不断增强,低成本风能、太阳能、储能将支撑全球能源转型,新能源生产与利用进入快速发展时期,2022年世界新能源消费平均占比达18.2%,预计2050年占比达到55%左右。世界能源在资源、消费地域、技术发展、人均消费量、节能领域、碳排放等存在分布不均的情况,化石能源低碳化提速、新能源规模化提速、能源管理智慧化提速的“三化提速”推动世界能源加快转型。中国式现代化强调人与自然和谐共生,积极稳妥推进碳达峰碳中和,深入推进能源革命,坚持“六性原则”,即能源生产的“独立性”、能源供给的“绿色性”、能源储备的“安全性”、能源消费的“高效性”、能源管理的“智慧性”、能源成本的“经济性”,加快规划建设新能源为主、新电力为主、新储能为主、新智慧能源为主“四个为主”绿色智慧的新型能源体系,确保能源安全。目前中国是能源大国但不是能源强国,能源消费结构有待进一步优化。中国能源安全发展新战略是能源消费革命、能源供给革命、能源技术革命、能源体制革命、全方面加强国际合作的“四个革命、一个合作”,推动中国能源革命和能源供应格局转变,由2022年含碳化石能源消费占比80%以上、碳基能源CO_(2)排放80%以上,转变到2060年非碳新能源消费占比80%以上、CO_(2)排放减少80%以上。加快新能源革命是建设能源强国、实现中国能源独立与民族复兴的战略选择,对实现“双碳”目标、构建新型绿色能源体系与建立绿色生态地球意义重大。

碳中和“超级能源系统”内涵、路径及意义——以鄂尔多斯盆地为例

超级含油气盆地为推动社会进步和人类发展提供了能源基础,在气候变化与“碳达峰碳中和”背景下,构建兼顾能源生产与碳中和的“超级能源系统”是转型方向。在加快构建以新能源、新电力、新储能、新智能“四新为主”的绿色+智慧能源体系框架下,以巨量地下煤炭/石油/天然气/地热与地上丰富风光能源资源高度叠合、化石能源与新能源融合协同开发利用的区域性智慧用能系统构成的“超级能源系统”与以碳循环为主线的碳中和系统相融合,在传统含油气盆地中研究选择具备建成世界级能源生产与碳中和示范大基地条件的碳中和“超级能源盆地”。鄂尔多斯盆地区位优势明显,化石能源和新能源资源丰富,CO_(2)源汇匹配优势显著,具备建成世界级能源生产与碳中和盆地的基础条件,以鄂尔多斯盆地为代表的碳中和“超级能源盆地”给出了传统含油气盆地转型方向。“煤炭+石油+天然气+新能源+CCUS(碳捕集、利用与封存)/CCS(碳捕集与封存)”融合发展理念与模式下,盆地区域内基本实现碳中和,进一步夯实能源生产保供能力,助力“双碳”目标实现,建立现代能源产业体系,推动地区绿色可持续发展。在中国率先建成以鄂尔多斯盆地为代表的世界级碳中和“超级能源系统”示范盆地,将重塑超级能源盆地勘探开发新理念与新模式,对全球“碳中和”下的能源革命具有重大意义。

超高效液相色谱-串联质谱法测定猪尿中12种禁用兽药残留

研究建立了超高效液相色谱-串联质谱测定猪尿中β_2-受体激动剂类、硝基呋喃代谢物类、硝基咪唑类、氯丙嗪、氯霉素等5类12种禁用兽药残留量同时检测的方法。试样中加入4.5 mL 0.2 mol/L乙酸铵溶液和40μL β-葡萄糖醛酸酶/芳基硫酸酯酶,37℃酶解2 h后,再加入1.5 mL 1.0 mol/L盐酸溶液和100μL 0.1 mol/L邻硝基苯甲醛溶液,经37℃衍生16 h,用8 mL乙酸乙酯萃取,下层水相用混合型阳离子交换固相萃取柱萃取,合并2次萃取液,氮气吹干复溶,正负离子多反应监测模式下检测,同位素内标法定量。12种化合物在各自范围内线性关系良好,相关系数(r)>0.99;氯霉素的检出限为0.05μg/L,定量限为0.1μg/L,其他化合物的检出限为0.25μg/L,定量限为0.5μg/L;在定量限1倍、2倍、10倍添加水平下的平均回收率为83.6%~115.3%, RSD为2.20%~12.34%。方法灵敏度高,稳定性好,定量准确,适用于猪尿中12种禁用兽药残留量的同时测定。

双重移相控制下双有源桥变换器最小回流功率全局优化控制

双有源桥(dual-active-bridge,DAB)DC-DC变换器通常用于能量转换。然而,传统的单移相控制使得变换器在输入电压和输出电压不匹配时产生较大的回流功率,特别是轻载情况下该现象更为严重。现有基于双重移相控制(dualphase-shift,DPS)的回流功率优化策略,尚未考虑全功率范围内的回流功率,也缺乏对所有工作模式下最小回流功率的研究。为此,该文提出一种考虑全功率范围、全工作模式的DPS最优控制策略。首先,详细阐述回流功率产生的机理,建立了不同工作模式的传输功率和回流功率数学模型。然后,计及不同工作模式的功率限值,将DPS控制的传输功率分成不同的功率区。在此基础上,提出了一种基于最小回流功率的DPS最优控制策略,通过分析不同工作模式下的优化路径获得各个功率区的最优移相角,进而提升DAB变换器的传输效率。最后,搭建实验平台验证所提最小回流功率控制策略的可行性。

1993—2022年中国应急管理与公共安全研究特征与趋势——基于CiteSpace和VOSviewer知识图谱分析

随着社会的不断发展和进步,新的风险和安全隐患不断涌现,对公共安全构成威胁。因此,如何有效应对各类突发事件、保障公共安全成为亟待解决的问题。结合中国近年来在应急管理与公共安全方面的主要研究成果,通过CiteSpace和VOSviewer软件采用文献计量分析方法,以1993—2022年中国知网(CNKI)数据库文献为研究对象,从可视化时间线变迁视角出发,绘制了中国应急管理与公共安全交织发展的知识图谱,分析中国应急管理与公共安全研究特征与趋势。结果表明:既有研究多聚焦于事件回顾、技术研究、政策建议、体系构建等问题,缺乏对未来新趋势的探索和展望;而本研究聚焦于整个萌生到发展成熟的过程,该过程形成了由“被动应急”走向“总体安全”的演化链条;由此提出理论框架,要以“总体国家安全观”为指导思想,以“智慧应急”为依托,以“总体安全”为目标,增强对公共安全议题的深入剖析,完善应急管理模式和技术体系,在中国开展情景化、实践化、能力化的应急实践,从而保障人民生命和财产安全,维护社会稳定和经济发展。

陆相页岩压裂试验与数值模拟——以鄂尔多斯盆地三叠系延长组7段为例

鄂尔多斯盆地三叠系延长组7段(长7段)页岩油资源潜力巨大,是增储上产的重要领域。然而由于陆相页岩黏土矿物含量高、纹层发育、结构和力学非均质性强,压裂改造难度大,亟需针对其压裂缝网演化特征进行研究。通过开展压裂试验与非连续数值模拟,获取了地应力和压裂液黏度对水力裂缝扩展的影响规律。研究认为:①当垂向应力差为15 MPa时,水力裂缝扩展主要受陆相页岩层理弱面控制,裂缝高度较小;当垂向应力差高于20 MPa时,水力裂缝扩展高度逐渐增大。②提高压裂液黏度能促进水力裂缝穿过层理弱面垂向扩展。③陆相页岩储层岩体结构是形成复杂缝网的基础,压裂裂缝最主要为被激活的天然裂缝。④压裂缝网主要由水平层理缝和与层理近似垂直的裂缝构成,当水平缝和垂直缝占比接近时,压裂改造效果较好。

晚三叠世卡尼期梅雨事件(CPE)在陆相盆地中的沉积学响应——以鄂尔多斯盆地延长组为例

卡尼期梅雨事件(CPE事件)是三叠纪地球上最显著的气候突变事件之一,而气候环境突变对内陆湖盆沉积物特征具有重要控制作用。以我国陆上最主要的含油气盆地——鄂尔多斯盆地三叠系延长组为例,在充分借鉴国内外有关全球古气候、事件沉积、陆相盆地烃源岩发育机理及异整合面等最新研究进展基础上,对延长组沉积与成藏问题重新思考与研究,取得了如下3点新认识:1)重新厘定了盆地上三叠统延长组卡尼期时限,明确了延长组CPE事件的沉积响应,认为卡尼阶底界大致相当于延长组长7与长8之间的地层界限,顶界相当于长4+5与长3之间的地层界限,CPE事件大致与“长7黑色页岩事件”沉积相对应;2)在卡尼期及CPE事件期间,延长组沉积期湖盆表现为“快速湖侵、震荡式缓慢湖退”特点,十分有利于优质烃源岩的发育;3)受卡尼期古气候及CPE事件影响,延长组内部发育上下两个由于气候环境突变而形成的异整合面,它们对油气分布均具有明显控制作用。该研究对于深入探讨延长组湖盆形成演化机理、沉积层序充填演化特征及指导油气勘探实践均有积极意义。

烃类源内微运移对页理型页岩油差异富集的影响——以鄂尔多斯盆地三叠系延长组长73亚段为例

受陆相页岩多纹层类型、高密度纹层特征的影响,烃类源内差异微运移成为控制不同岩相页岩含油性及可动性的重要因素。以鄂尔多斯盆地10口系统取心井为对象,利用X-射线衍射、薄片观察、扫描电镜、氮气吸附、激光共聚焦、地球化学等分析测试手段,结合测井及试油资料,对三叠系延长组长73亚段页岩中烃类的微运移现象及微运移机理进行分析。研究发现页岩中富有机质纹层生成的原油普遍发生微米—毫米尺度的微运移,其中生烃增压提供了微运移动力;频繁发育的刚性纹层为微运移的烃类提供大量聚集空间;生烃增压缝—页理缝—微裂缝为微运移提供了通道;纹层矿物组成差异造成烃类分异。纹层的组合类型及差异微运移机理决定了长英质纹层页岩和凝灰质纹层页岩具有相对较好的含油性及可动性,是中—高成熟度页理型页岩油风险勘探的主要岩相类型。7口直井在长73亚段页岩中试油获10t/d以上的工业油流,证明长73亚段页岩段含油性好,水平井开发提产潜力大,有望成为鄂尔多斯盆地页岩油增储上产的接替领域。

基于地震属性智能融合的湖相重力流沉积致密砂岩储层预测

湖相重力流是目前沉积学研究的热点与难点,也是致密油、页岩油富集的有利场所,鄂尔多斯盆地庆城油田三叠系延长组作为致密油、页岩油的典型代表已显示出巨大的勘探开发前景。然而,由于湖相重力流砂体分布认识不清,导致油田并未达到预期的开发效率。本文采用支持向量机(SVR)的机器学习方法,先优选频段再优选属性,建立分频属性与测井解释砂体厚度的非线性映射关系,实现了致密砂岩的定量预测。研究结果表明,低频地震属性适合预测厚层砂体,高频地震属性适合预测薄层砂体;采用机器学习的方法,将不同频率的地震属性智能融合,能够兼顾预测不同厚度砂体,既提高了地震属性的解释精度,又降低了地震解释的多解性,实现了砂体厚度的定量预测。检验结果显示,智能融合属性与砂体厚度的分布趋势与值域区间基本一致,智能融合属性预测砂体分布的可靠性明显提高,与测井解释砂体厚度的相关性由0.60提高至0.79,大多数井点处预测的砂体厚度误差小于5 m。继而,根据融合属性与测井解释,刻画了研究区的沉积微相展布特征:研究区目的层发育湖底扇沉积,细分为分支水道、朵叶主体、朵叶侧缘、滑塌体与朵叶间/水道间5种沉积微相;砂体主体呈扇形连片式沉积,厚度顺物源方向逐渐减薄;分支水道呈窄条带状树形分叉,下切发育于朵叶体之上;朵叶体沉积为研究区的沉积主体;滑塌体为湖底扇前端失稳滑塌形成的小规模孤立砂体,长轴方向多平行于湖底扇前端。研究成果对油田下一步高效开发具有重要意义。

安徽省春性小麦区试品系主要品质性状分析

为探究安徽省春性小麦品质育种进展,对参加安徽省淮南片2010-2019年春性小麦区试的154个品系(227份)样品进行品质性状分析,并根据不同品质分类标准进行评价。结果表明,供试材料平均容重为788.7±18.4 g·L-1,硬度指数为57.1±8.8,粗蛋白含量(干基)为13.24%±1.07%,湿面筋含量(14%水分基)为28.2%±3.0%,沉淀值(Zeleny法)为35.2±9.7 mL,吸水率为56.3%±3.8%,稳定时间为4.4±3.1 min,最大拉伸阻力为388±147 EU,能量为81.2±32.5 cm 2。品质性状之间存在显著相关性,其中,粗蛋白含量与湿面筋含量、吸水率与硬度指数的相关系数均大于0.8,分别为0.898和0.888。各品质性状年份间表现不同的变化趋势,容重、湿面筋含量、沉淀值、稳定时间、最大拉伸阻力年份间波动明显,但没有明显规律;粗蛋白含量和能量呈缓慢下降趋势;而吸水率和硬度指数则比较稳定。根据国家小麦品种品质分类标准,227份样品中,有3.08%、11.01%和0.88%的样品全部指标分别达到中强筋、中筋和弱筋小麦标准,没有样品达到强筋小麦标准,多数品系品质指标之间存在强、中强、中、弱筋交错不协调现象。通过审定的品种中,仅有1个达到弱筋标准。

湘东北横洞钴矿床钴的富集机制:来自黄铁矿的微区结构、成分和硫同位素证据

世界上典型热液脉型钴矿床,如五元素(Ag-Bi-Co-Ni-As±U)矿床,因其高的钴品位(高达8%)而具有重要的经济价值和研究意义,该类矿床以自然元素和砷化物组合为特征。不同于五元素矿床,湘东北横洞热液脉型钴矿床(中型,品位约0.04%)的矿石矿物组合为黄铁矿+黄铜矿+闪锌矿+方铅矿+磁黄铁矿,目前对该矿床中含钴矿物的特征及钴的富集机制尚不清楚。本文在详细的矿相学工作基础上,采用EPMA、EBSD、LA-ICPMS和LA-MC-ICPMS等多种分析方法,对其黄铁矿开展了精细结构、成分和硫同位素分析。将黄铁矿划分为PyI、PyII和PyIII三个世代。其中,PyII是Co的重要载体,常呈丝带状、不规则状或韵律环带交代PyI或呈细粒状产出,其Co含量高达52141×10^(-6),明显高于其他世代黄铁矿。黄铁矿中Co与Fe具有较好的负相关性,表明Co主要呈类质同象的形式置换Fe存于黄铁矿晶格中。而黄铁矿中高的Co/Ni比值(1.05~393)和Se含量(10.69×10^(-6)~129×10^(-6))则暗示了其热液成因。此外,PyII与PyI之间具有不规则港湾状接触界面、突变的化学成分以及相近的晶体取向,这些暗示了富钴的PyII系含钴流体与围岩及早阶段黄铁矿快速反应的产物,溶解再沉淀的动力学过程是控制PyII的形成机制。不同世代黄铁矿的δ34 S V-CDT值接近,变化范围为-13.12‰~-8.70‰,与围岩地层的硫同位素特征接近。结合湘东北结晶基底高的Co含量(30.4×10^(-6)~72.3×10^(-6))和以往流体包裹体显微测温结果,认为在晚侏罗世-早白垩世期间,NE-ENE向的长沙-平江断裂带走滑剪切活动使得深源热液流体从结晶基底连云山岩群活化萃取了金属钴,富钴热液沿走滑断裂向上运移至成矿部位,再因压力周期性变化引起流体发生不混溶作用进而分离,导致钴金属络合物失稳,最后钴沉淀富集成矿。通过与世界上典型热液脉型钴矿床成矿特征的对比,提出流体低的盐度和低砷、高硫的特征是造成横洞钴矿床矿物组合简单的主要控制因素。

Authigenic silica in continental lacustrine shale and its hydrocarbon significance

Taking lake basin shales of the Triassic Yanchang Formation in the Ordos Basin,NW China and the Cretaceous Qingshankou Formation in the Songliao Basin,NE China as research objects,the characteristics and origins of different types of silica in the shales have been studied by means of core observation,thin section identification,cathodoluminescence,X-ray diffraction analysis,scanning electron microscope(SEM),electron probe and rock pyrolysis.The results shows that the origins of silica include felsic mineral dissolution,tuffite devitrification,clay mineral transformation and siliceous mineral metasomatism.The silica formed by feldspar dissolution commonly appears as spots and veins,with low degree of crystallization,and is largely aqueous opal mineral,with an average Si O2 content of 67.2%.Silica formed by devitrification of tuffite mainly occurs in two forms,amorphous silica and authigenic quartz with better crystal shape.The authigenic silica formed during the transformation of clay minerals is embedded in the clay minerals in the form of micron-scale plates and small flakes,or mixed with clay minerals in a dispersed state.The authigenic quartz formed by siliceous mineral metasomatism is in better angular crystal shape,and has an average Si O2 content of 87%.The authigenic siliceous mineral content is positively correlated with the content of terrigenous felsic minerals.The pressure solution of felsic minerals is the main source of authigenic siliceous minerals,followed by the transformation of clay minerals,and the organic matter has some boost on the formation of authigenic silica.The authigenic siliceous materials of different origins have different geological characteristics and occurrence states from terrigenous quartz,which would affect the storage performance,seepage capacity and fracturing effect of continental shale.Although the organic-rich shale has high silica content,different from terrigenous quartz,authigenic silica in this kind of shale mostly floats and disperse in clay minerals,which would have negative effect on the formation of complex fractures in fracturing,fracture support ability after fracturing,and formation of effective seepage channels.Calculating the brittleness index of shale intervals only based on the composition of brittle minerals cannot accurately characterize mechanical characteristics of continental shale oil reservoirs,and would affect comprehensive evaluation and selection of continental shale oil“sweet spots”.

鄂尔多斯盆地延长组长7_(3)亚段页岩油特征及勘探方向

通过对鄂尔多斯盆地三叠系延长组7段3亚段(简称长7_(3)亚段)岩心观察、实验分析测试、测-录井等资料分析,揭示长7_(3)亚段多类型页岩油发育的地质特征及富集规律,探讨多类型页岩油勘探潜力及攻关方向。研究表明:①长7_(3)亚段发育运移-滞留复合型和滞留型2类页岩油,运移-滞留复合型储集层为砂质碎屑流、低密度浊流成因的砂质纹层和半深湖—深湖富有机质泥页岩纹层频繁互层叠置的组合段,滞留型页岩油储集层为页理及显微纹层频繁发育的黑色页岩,运移-滞留复合型页岩油品质略好于滞留型页岩油。②优质烃源岩提供大量高势能富烃优质流体;源储压差为渗流条件较好的贫有机质砂岩类薄夹层和页岩中的长英质纹层、凝灰质纹层及页理缝原油聚集提供动力;生烃增压缝-页理缝-微裂缝为原油微运移提供高速通道;频繁发育的砂岩夹层及长英质纹层不仅为烃类规模聚集提供有效的储集空间,还能有效提高烃类的可动性。③环洼富砂区是运移-滞留复合型页岩油规模勘探的主要方向,成熟深洼区是中高成熟度滞留型页岩油风险勘探的主要方向,围绕低熟深洼区积极推进原位转化研究和现场实施是中低成熟度滞留型页岩油勘探的主要攻关方向。

古地貌恢复及其对重力流沉积砂体的控制作用:以鄂尔多斯盆地三叠系延长组长7_(3)亚段为例

鄂尔多斯盆地三叠系延长组长73亚段沉积体系和砂体成因类型及展布特征受湖盆底部形态控制明显,不同地区砂体类型、成因及空间展布各异。根据岩心、钻井、测井等资料运用印模法与沉积学方法精确地恢复了鄂尔多斯盆地三叠系延长组长73亚段的古地貌,并对微古地貌单元进行精细刻画,在此基础上分析了古地貌对盆地延长组长73亚段沉积体系和砂体成因类型及展布特征的控制作用。研究表明:长73期古地貌整体呈东缓西陡的不对称坳陷形态,明确了研究区发育高地、坡折带、湖底深洼(凹)、湖底平原、湖底古隆、湖底古脊和古沟道7个微古地貌单元。研究区延长组长73亚段重力流沉积体系受古地貌控制较明显,从湖盆边缘至湖盆中心依次发育三角洲前缘沉积、沟道型重力流沉积、半深湖-深湖沉积,从坡折带至湖盆中央,重力流沉积类型逐渐从砂质碎屑流沉积转换为浊流沉积。古地貌形态控制着研究区延长组长73亚段重力流砂体的整体展布,而高地、坡折带及古沟道等微古地貌单元则进一步控制重力流砂体的物源方向、成因类型、运输方向、横向连通性及展布形态等。

Factors controlling the reservoir accumulation of Triassic Chang 6 Member in Jiyuan-Wuqi area,Ordos Basin,NW China

In the Triassic Yanchang Formation, Jiyuan-Wuqi area, Ordos Basin, the Chang 6 reservoir is contacted to the Chang 7 high-quality source rock, but the oil pools are unevenly distributed, and complex in oil and water distribution. Through cores observation and fracture statistics, combined with comprehensive analyses of physical property, mercury injection, logging and geochemical data, and comparisons of the sandbodies scales, reservoir physical properties, argillaceous laminae and fractures between source and reservoir in the eastern and western oil-bearing areas and in the central water producing area, it is found that the hydrocarbon accumulation patterns are different in the eastern, central and western areas, and the characteristics of hydrocarbon migration under the background of double-provenance were sorted out. The study results show that the crude oil in the eastern area has different Pr/Ph and sterane distribution from that in the western area. The oil and gas primarily migrated vertically. The high-quality source rocks and favorable source-reservoir-cap combinations lay the foundation for large-scale oil and gas accumulations. Vertically, the oil and gas enrichment is controlled by the scale of sandbody and the difference of physical properties, while on the plane, it is controlled by the connectivity of sandbodies, the argillaceous laminae between source rock and reservoir, the reservoir physical property and the fractures. The sandbodies of oil-rich zones in the eastern and western areas have large thickness, low shale content, good physical properties, weak heterogeneity, few argillaceous laminae and abundant fractures, all of which are favorable for the vertical migration and accumulation of oil and gas. In contrast, in the middle area with converging provenances, the reservoirs, composed of thin sandbodies, features rapid variation in lithology and physical properties, strong heterogeneity, poor continuity of sandbodies, abundant argillaceous laminae between source rock and reservoir, and few fractures, makes it difficult for the oil and gas to migrate vertically, and results in low oil enrichment degree ultimately. For the exploration of continental multiple-provenance tight reservoirs, not only the good-property source rocks and reservoirs, but more importantly the source-reservoir contact relationship and the effect of fractures on the hydrocarbon migration and accumulation should be considered.

陆相黑色页岩沉积环境及有机质富集机制——以鄂尔多斯盆地长7段为例

【目的】元素地球化学特征分析与古环境恢复是深入认识页岩层系中有机质富集机制的重要前提。【方法】以鄂尔多斯盆地三叠系延长组7段沉积时期湖盆不同相带(浅湖、滨浅湖、半深湖—深湖)的黑色页岩为研究对象,开展了5口代表性钻井长7段页岩的岩石学、古生物学、有机地球化学、元素地球化学等分析,以此探讨陆相黑色页岩的沉积环境及其有机质富集机制。【结果】鄂尔多斯湖盆长7段页岩层系不同黑色页岩层段(长7_(3)、长7_(2)和长7_(1)亚段)具有差异地球化学特征与沉积环境:(1)长7_(3)页岩有机质最为富集(TOC平均含量约为8.21%),其异常高有机质页岩最厚,其次为长7_(1)和长7_(2);(2)主、微量元素特征显示湖盆长7段沉积时期总体上为岛弧及活动大陆边缘构造背景,以长英质与基性岩混合的物源为主,含少量安山岩岛弧物源,但长7_(3)时期陆源碎屑输入强度明显低于长7_(2)与长7_(1);(3)较高CIAcorr和Cvalue值表明长7段沉积时期整体处于高温多雨湿润气候,其中长7_(3)时期温度与湿度最高;(4)Sr/Ba和Rb/K_(2)O比值指示长7_(3)时期整体为淡水环境,并局部发生微咸化,而长7_(2)和长7_(1)表现为相对稳定的淡水环境。【结论】通过对长7段典型火山灰层上、下黑色页岩高精度地球化学特征对比分析,并结合长7不同时期火山活动特征与有机质富集主控因素探讨,认为鄂尔多斯盆地长7黑色页岩有机质富集,特别是异常高有机质规模富集,与火山活动(喷发)事件密切相关:火山活动能够引发一系列连锁效应,包括“迟滞”期初级生产力“爆发式”增长、水体还原性增强等,从而有利于异常高有机质规模沉积。