改进的砂泥岩地层中断裂封闭性评价SGR法及应用

SGR法评价断裂在砂泥岩地层中侧向封闭性时,通常采用统计得到的常数作为下限值,导致评价结果与勘探实践存在着较大的偏差。针对上述问题,采用断裂倾角、断层岩压实成岩时间、目的储层泥质含量和压实成岩时间,确定断裂在砂泥岩地层中侧向封闭所需的最小断层岩泥质含量。研究表明:最小断层泥质含量是基于封闭机理所求的一个变值,解决了SGR法统计采用常数值存在偏差的问题,有效提高了侧向封闭性评价的准确性。将该方法应用于海拉尔盆地贝尔凹陷西部呼和诺尔构造带F3断裂在南二段砂泥岩储层的侧向封闭性评价,获得了测点5、7、8和12—15处F3断裂在南二段砂岩储层内侧向封闭,而其余测点处侧向不封闭的重要认识。该认识与油气主要分布在测点7、8、12、14处的情况吻合。研究成果对含油气盆地砂泥岩地层断层型油气藏分布特征及指明油气勘探方向具有重要借鉴意义。

胜利油田油藏描述技术回顾与发展方向

胜利油田为典型的陆相复式油气区,油藏类型多、含油层系多、断裂系统复杂,20世纪90年代初进入含水率为90%以上的特高含水开发阶段,如何针对不同类型油藏和开发阶段,精细刻画地下储层变化、精准认识剩余油,是实现高含水老油田提高采收率的基础。为此,从1996年始开展了针对老油田剩余油挖潜的精细油藏描述,通过精细储层构型表征、低序级断层精细描述、砂砾岩期次划分与连通性评价、薄互层滩坝砂储层预测、三维精细地质建模及剩余油精细描述等关键技术攻关,以及多轮次油藏描述技术迭代,形成了一套胜利特色的精细油藏描述技术,编制了精细油藏描述技术规范。截至2023年累计描述开发单元600余个,覆盖石油地质储量为43.6×108 t,建模数模技术在老区调整和新区方案编制中得到广泛应用,有效支撑了油田的规模建产与效益稳产。系统分析胜利油田油藏描述技术发展历程,总结不同类型油藏形成的特色技术,分析特高含水后期老油田精细油藏描述面临的5项挑战,阐述下一步油藏描述技术的5个发展方向,对推动陆相油田精细油藏描述技术具有指导和借鉴意义。

地质力学参数智能预测技术进展与发展方向

随着人工智能技术在油气勘探领域应用的不断深入,地质力学参数预测从传统方法向智能化转型已成为必然趋势。本文系统归纳分析了机器学习算法在岩石力学参数直接与间接预测,地层孔隙压力钻前预测、随钻监测和钻后评估,一维地应力和三维地应力场预测中的应用现状,对比了不同预测任务下的机器学习模型、输入参数、样本数据量、输出参数以及模型预测性能。研究发现:相比于室内试验、现场测试和经验模型计算,机器学习算法在地质力学参数预测方面的准确性、时效性和适用性具有明显优势;集成模型、深度学习模型和物理约束神经网络模型凭借其准确性、鲁棒性、泛化能力和可解释性,已成为当前研究的热点和重点;但现有研究以一维地质力学参数的钻后预测为主,因而无法有效进行钻前和随钻三维地质力学参数预测。为了加快地质力学参数向智能化、数字化转型,本文提出了一种地质力学参数智能预测框架,该框架考虑地震、测井、录井等多源数据对地质力学参数预测的影响,通过数据+物理双驱动的机器学习模型进行三维地质力学参数的预测,并通过正钻井数据进行模型的实时更新,从而实现区域三维地质力学参数的钻前预测、随钻监测以及钻后评估。此外,分析了地质力学参数智能预测面临的关键技术难题:①实现非结构化数据类型的转换,降低数据集复杂度,确保数据的一致性和可比性;②开展多源数据融合研究,构建包括地震、测井、录井、室内试验、现场测试等方面的多源数据集,并进行数据处理、特征选择等工作;③加强机器学习模型研究以提升性能,采用集成模型提升预测精度,融入机理模型和领域知识提升模型鲁棒性和可解释性。

陆相页岩油甜点参数测井定量评价方法及应用

中国陆相页岩油储层按照沉积特征及生储组合关系分为夹层型、混积型和泥纹型3种类型,根据不同主控因素和面临的开发难点,可分为复杂构造影响型、储层强非均质型、高黏土难改造型、高黏油难流动型和低含油饱和度型5种类型。不同类型储层高产稳产的主控因素差异性大,甜点纵横向精细刻画、富集规律及展布特征是规模效益开发的关键。通过建立矿物组分、孔隙度、力学及脆性计算模型,结合直井试油和水平井生产动态资料,优选不同类型储层产能主控因素和核心参数,建立甜点分类评价标准,优选储层甜点段。综合分析表明,陆相页岩油优质甜点多为中、高TOC背景下,核磁大孔隙发育、页理缝有效性好(裂缝发育)的油气富集层,并具有良好顶板封盖条件。研究成果已经在多个油田的页岩油水平井靶窗优选和随钻跟踪中得到应用,可为页岩油勘探开发提供理论指导与技术支撑。

深部煤系气合采压裂裂缝扩展规律及其主控因素

【目的】煤系气合采是提高我国非常规天然气单井产量的重要开发方式。然而,煤系气储层物质组成截然不同、物理性质差异巨大,导致煤系气合采储层在压裂过程中裂缝在不同储层内的扩展方式和发育程度存在不确定性。如何协调好多储层改造实现多气共采对于降低煤系气开发成本、提高产能至关重要。【方法】以鄂尔多斯盆地东北缘临兴区块为例,剖析影响煤系气储层合层压裂效果的地质因素、工程因素,利用数值模拟方法,研究不同储层内压裂裂缝的扩展规律,并对合层压裂提出针对性建议。【结果】结果表明,储隔层最小水平主应力差、抗拉强度差、泵注排量和黏度的增大有利于缝高和缝宽的扩展,其数值越大,裂缝的穿层能力越强。岩层的最小水平主应力和压裂液黏度主要影响储层中裂缝宽度,具体表现为,岩层相对最小水平主应力越大或压裂液的黏度越小,裂缝宽度越小。储隔层弹性模量差和泊松比差的变化对整体压裂效果的影响较小,但弹性模量差增大会减少裂缝穿层时间,使裂缝更快到达极限高度。【结论】基于上述研究,提出了临兴地区煤系气合采储层优选方案及排采建议,即应优先选取储隔层最小水平主应力差在0~4 MPa、抗拉强度差大于4.5 MPa的储层进行合采压裂,并以大于4 m^(3)/min的泵注排量进行开采,从而实现更高效的资源开发。

页岩油气地质-工程一体化理论与技术研究进展

地质-工程一体化是实现我国复杂油气藏和非常规油气藏效益开发必由之路,亟需从理念向方法论转变,以期更好地促进针对性、适应性和创新性理论的技术探索与应用。遵循系统工程的原则,按照全生命周期可接受效益指标下最大化采收率的开发理念,重点研究了地质流体演化动力学模型、高分辨率裂缝表征方法与技术、立体开发智能布井方法与技术、高分辨率岩石力学参数测量与建模、超大型真三轴压裂模拟实验系统、空间应力场主动利用机理与调控机制、页岩油可流动性机理与评价方法和页岩油压裂提高采收率一体化关键材料,与实践充分结合,提出了岩石复杂组构和强非均质性是形成复杂缝网的自然基础、“构造驱动、多因素综合”立体开发布井等理论认识和创新思路,表明地质-工程一体化从理念向方法论转变的可行性和必要性,强调了辩证与发散思维在推动理论创新与技术突破中的核心作用,为我国页岩油气效益开发提供新思路。

Hydrocarbon accumulation and orderly distribution of whole petroleum system in marine carbonate rocks of Sichuan Basin,SW China

Based on the situation and progress of marine oil/gas exploration in the Sichuan Basin,SW China,the whole petroleum system is divided for marine carbonate rocks of the basin according to the combinations of hydrocarbon accumulation elements,especially the source rock.The hydrocarbon accumulation characteristics of each whole petroleum system are analyzed,the patterns of integrated conventional and unconventional hydrocarbon accumulation are summarized,and the favorable exploration targets are proposed.Under the control of multiple extensional-convergent tectonic cycles,the marine carbonate rocks of the Sichuan Basin contain three sets of regional source rocks and three sets of regional cap rocks,and can be divided into the Cambrian,Silurian and Permian whole petroleum systems.These whole petroleum systems present mainly independent hydrocarbon accumulation,containing natural gas of affinity individually.Locally,large fault zones run through multiple whole petroleum systems,forming a fault-controlled complex whole petroleum system.The hydrocarbon accumulation sequence of continental shelf facies shale gas accumulation,marginal platform facies-controlled gas reservoirs,and intra-platform fault-and facies-controlled gas reservoirs is common in the whole petroleum system,with a stereoscopic accumulation and orderly distribution pattern.High-quality source rock is fundamental to the formation of large gas fields,and natural gas in a whole petroleum system is generally enriched near and within the source rocks.The development and maintenance of large-scale reservoirs are essential for natural gas enrichment,multiple sources,oil and gas transformation,and dynamic adjustment are the characteristics of marine petroleum accumulation,and good preservation conditions are critical to natural gas accumulation.Large-scale marginal-platform reef-bank facies zones,deep shale gas,and large-scale lithological complexes related to source-connected faults are future marine hydrocarbon exploration targets in the Sichuan Basin.

基于力学时变性的页岩油藏四维地应力演化规律研究

裂缝对页岩岩石力学性质影响突出,准确表征含裂缝页岩的岩石力学性质变化是实现页岩油藏压裂-投产过程中四维地应力场精准刻画的重要基础。已有四维地应力研究通常认为应力变化主要源于孔隙压力改变,未考虑岩石力学性质变化对四维地应力的影响。利用在线CT实验,明晰了孔隙压力与页岩孔缝体积的关系,依据应变能理论,推导了裂缝体积与页岩泊松比、弹性模量的理论关系,建立了孔隙压力与泊松比、弹性模量的时变理论模型。结果表明,层理缝开启是页岩岩石力学参数具有时变性的主要原因,孔隙压力越大,裂缝开启条数越多,裂缝空间呈指数型增长。随裂缝体积增加,页岩泊松比快速增加、杨氏模量快速减小,页岩强度大幅降低。以济阳坳陷页岩为例开展分析,裂缝体积占比提高至1%时,杨氏模量由37.5GPa下降至15.06GPa,泊松比由0.22上升至0.35。依托数值模拟方法对比分析岩石力学参数时变性对四维地应力演化的影响,考虑岩石力学时变性特征的四维地应力模拟能够更好地表征页岩压裂-投产过程中的应力大小演化与方向偏转的规律,与实际油藏压裂-投产过程中的四维地应力演化规律更加吻合,模拟结果更加可靠。研究成果能够为页岩油立体井组合理部署、优化设计、风险预警等提供理论支撑。

巴西圆盘拉伸强度测试在岩石力学中的发展综述及新见解

准确获取岩石抗拉强度,全面了解岩石拉伸破坏演化机制,是岩石力学理论研究和岩体工程应用的关键问题之一。由于直接拉伸试验存在试样夹持困难、端部应力集中显著、试验成功率低等诸多局限性难题,岩石类材料抗拉强度通常采用间接方法测试。而巴西圆盘试验作为间接方法中最被广泛使用的测试技术,自提出就因其特殊的力学机制而成为了岩石力学领域的研究热点,但同时其结果的准确性和有效性也受到了广泛的质疑与讨论。本文系统调研了巴西圆盘试验相关的室内试验、解析模型和数值模拟研究,总结并分析了该方法的发展趋势、形成的不同试验标准以及每种标准提出的基本依据和适用性。基于国内研究中的试验数据,对比了巴西圆盘和直接拉伸试验在测试结果上的差异,分析了控制巴西圆盘有效起裂的关键因素,明确了外在因素(加载条件、几何形状)和内在因素(力学性质、非均质性)对巴西圆盘断裂机制和试验结果的影响。最后,从初始裂纹萌生和扩展裂纹延伸两个阶段重新讨论了巴西圆盘测试岩石拉伸强度在实际条件下的有效性,并结合近年来几种创新型的岩石拉伸测试新方法,指出了岩石力学领域抗拉强度测试方法的发展方向。

基于灰色关联分析法评价老气田开发潜力——以四川盆地气藏为例

老气田的储层参数差异较大,无法根据单个指标评估整个区块的开发潜力。为此,重新构建老气田开发潜力评价指标体系,从储层物性、储量规模及动用情况、生产动态、地层情况等方面对其开发潜力展开综合评价。以四川盆地气藏为例,从12个区块资料中筛选出12项相关开发评价指标,利用灰色关联分析法对这些区块的开发潜力进行综合评价及优选排序。经评价和优选,将老气田划分为Ⅰ、Ⅱ、Ⅲ、Ⅳ类潜力区块,其中开发潜力较大的Ⅰ类、Ⅱ类区块主要包括LHC、TSN、HLC、WQJ等4个区块。此评价结果可作为针对老气田潜力区块进行优选的理论依据。

金家油田沙一段高分辨率层序地层研究

在高分辨率层序地层学理论方法的指导下,结合地震、岩心及测井资料,识别出金家油田沙一段不整合面、最大湖泛面、初始湖泛面、一般湖泛面和岩性界面等5类层序界面,阐述各级次层序界面的特征和意义。在层序界面控制下,依据基地层旋回性和沉积学特征,将金家油田沙一段划分为1个长期旋回(三级层序)、3个中期旋回(体系域)和10个短期旋回,其中短期旋回可划分为向上变“深”型、向上变“浅”型和对称型3种结构类型。并讨论基准面旋回变化过程中,不同体系域内短期旋回的沉积序列、结构类型和分布模式,建立以短期旋回层序为等时地层对比单元的全区层序地层格架,分析格架内砂体沉积特征,为沙一段砂体的等时追踪对比、几何形态和储层结构描述等精细地质研究奠定基础。

泌阳凹陷井楼八区低序级断层识别及其应用

泌阳凹陷井楼八区发育较多低序级断层,常规技术难以识别,在地层精细对比的基础上,运用井间地震资料联合、地震等时切片及油藏动态分析等技术,精细刻画了20m以下低序级断层产状,为注采调整提供地质依据。

Enrichment model and major controlling factors of below-source tight oil in Lower Cretaceous Fuyu reservoirs in northern Songliao Basin,NE China

Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics,the tight oil enrichment model and its major controlling factors.First,the Quantou Formation is overlaid by high-quality source rocks of the Upper Cretaceous Qingshankou Formation,with the development of nose structure around sag and the broad and continuous distribution of sand bodies.The reservoirs are tight on the whole.Second,the configuration of multiple elements,such as high-quality source rocks,reservoir rocks,fault,overpressure and structure,controls the tight oil enrichment in the Fuyu reservoirs.The source-reservoir combination controls the tight oil distribution pattern.The pressure difference between source and reservoir drives the charging of tight oil.The fault-sandbody transport system determines the migration and accumulation of oil and gas.The positive structure is the favorable place for tight oil enrichment,and the fault-horst zone is the key part of syncline area for tight oil exploration.Third,based on the source-reservoir relationship,transport mode,accumulation dynamics and other elements,three tight oil enrichment models are recognized in the Fuyu reservoirs:(1)vertical or lateral migration of hydrocarbon from source rocks to adjacent reservoir rocks,that is,driven by overpressure,hydrocarbon generated is migrated vertically or laterally to and accumulates in the adjacent reservoir rocks;(2)transport of hydrocarbon through faults between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downward through faults to the sandbodies that are separated from the source rocks;and(3)migration of hydrocarbon through faults and sandbodies between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downwards through faults to the reservoir rocks that are separated from the source rocks,and then migrates laterally through sandbodies.Fourth,the differences in oil source conditions,charging drive,fault distribution,sandbody and reservoir physical properties cause the differential enrichment of tight oil in the Fuyu reservoirs.Comprehensive analysis suggests that the Fuyu reservoir in the Qijia-Gulong Sag has good conditions for tight oil enrichment and has been less explored,and it is an important new zone for tight oil exploration in the future.

An intelligent automatic correlation method of oilbearing strata based on pattern constraints:An example of accretionary stratigraphy of Shishen 100 block in Shinan Oilfield of Bohai Bay Basin,East China

Aiming at the problem that the data-driven automatic correlation methods which are difficult to adapt to the automatic correlation of oil-bearing strata with large changes in lateral sedimentary facies and strata thickness,an intelligent automatic correlation method of oil-bearing strata based on pattern constraints is formed.We propose to introduce knowledge-driven in automatic correlation of oil-bearing strata,constraining the correlation process by stratigraphic sedimentary patterns and improving the similarity measuring machine and conditional constraint dynamic time warping algorithm to automate the correlation of marker layers and the interfaces of each stratum.The application in Shishen 100 block in the Shinan Oilfield of the Bohai Bay Basin shows that the coincidence rate of the marker layers identified by this method is over 95.00%,and the average coincidence rate of identified oil-bearing strata reaches 90.02% compared to artificial correlation results,which is about 17 percentage points higher than that of the existing automatic correlation methods.The accuracy of the automatic correlation of oil-bearing strata has been effectively improved.

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.

基于不连续边界识别的辫状河储层夹层研究——以渤海海域P油田馆陶组为例

渤海海域P油田发育河道切叠频繁的辫状河储层,已钻井揭示其储层内夹层发育,导致钻后水淹状态和产能差异较大,夹层精细刻画和精确表征是剩余油挖潜的关键。分析了P油田夹层分布特征及成因,认为夹层分布与构型边界具有较好的相关性,因此提出了基于不连续边界识别的夹层刻画方法。通过两级不连续边界分析识别出边界河道、内部主河道和内部次河道,分别对应复合心滩边界河道充填、单心滩边界河道充填和串沟充填3种夹层类型,建立了各级河道的定量判别标准,确定了夹层厚度中心线;根据研究区300个井组侧钻井资料,分析确定了夹层的平均厚度和翼展宽度;利用分类插值和井点校正得到了夹层厚度分布图。结果表明,P油田馆陶组辫状河储层夹层多以宽翼条带状分布,3种夹层的平均厚度分别为3、2和1m,平均翼展宽度分别为100、50和25m。应用本方法对C10井区L50小层进行了精细研究,夹层刻画结果有效指导了剩余油的挖潜。

基于储层质量综合指数的砂砾岩储层差异分布评价——以渤海M油田东三段为例

渤海M油田东三段砂砾岩储集体埋藏深度大、地震资料品质差,难以满足直接刻画储层的精度需求。利用钻井资料,通过主成分分析优选表征储层质量的参数,结合熵权法构建储层质量综合指数,开展了研究区东三段砂砾岩体内幕储层质量的差异分布评价,并通过动态监测资料进行了验证。结果表明:①依据储层质量综合指数累计概率分布斜率差异将研究区东三段划分为Ⅰ、Ⅱ、Ⅲ三类储层,储层质量依次为优质、中等和差等;②纵向上,片状洪流作用下(8~5小层)的储层质量品质整体差于牵引流作用下(4~1小层)的砂体沉积,其中3小层储层质量相对最好;③平面上,砂体几何展布形态经历了条带状(8~5小层)→朵叶状(4~2小层)→指状(1小层)演化。研究成果可为相似地质条件下的砂砾岩储层质量分布评价提供一定方法借鉴。

文南油田开发中后期沉积微相精细研究

重新认识处于开发中后期油藏的沉积环境、沉积微相及其特征 ,建立准确的储集层模型 ,对于查明剩余油分布和挖掘剩余油潜力、提高采收率具有重要的现实意义。通过对东濮凹陷文南油田沙二下亚段古生物特征、地球化学特征、沉积构造特征、储集层岩性特征、粒度特征等方面的综合分析 ,认为其沙二下亚段为干旱炎热气候条件下的间歇性涨缩浅湖环境下发育的浅水三角洲和滨浅湖沉积体系 ;划分出三角洲前缘水下分流河道、水下溢岸砂、水下天然堤、水下分流间湾、前三角洲砂泥、滨浅湖泥等 6种沉积微相类型 ;分析各沉积微相特征 ,指出水下分流河道砂体储集物性最好 ,水下溢岸砂次之。图 5表 1参

利用基于Russell近似的弹性波阻抗反演进行储层描述和流体识别

本文基于Russell提出的多孔流体饱和弹性介质的佐普里兹方程形式的近似公式,借鉴弹性波阻抗的原理,推导了标准化的以流体因子f、拉梅常数μ和密度ρ表示的新的弹性波阻抗公式。通过反演可以直接从弹性波阻抗数据体中提取流体因子f和拉梅常数μ数据体,从而将弹性波阻抗与流体因子联系起来,兼顾了常规弹性波阻抗反演的高抗噪性以及利用流体因子识别流体的直观性,并且流体因子f的直接提取方法减少了间接计算的误差累积过程,为储层流体预测提供了一种新的途径。利用文中方法在SL油田Y3工区提取的流体因子f可以有效地区分出不同的流体类型,流体因子f对流体类型的敏感程度要优于其他常规属性,对沙二段储层流体的识别更加准确可靠,在储层流体识别与寻找剩余油方面显示了较好的应用效果。

层状断块油藏特高含水期细分开发技术

辛 4 7断块是一个高丰度的层状断块油藏 ,采用分层系注水开发。在同套开发井网内 ,由于受非均质的影响 ,层间水驱状况不均衡。 1999年 ,断块进入特高含水期后 ,层间矛盾加剧 ,原有开发层系和井网已不适应油藏挖潜需要。 2 0 0 0年 ,在辛 4 7断块开展了精细油藏描述和细分开发工作 ,效果非常明显 ,断块含水下降了 3% ,采油速度提高了 0 38% ,采收率提高了 5 %。实践表明 ,采用精细油藏描述和细分开发的技术方法 ,对提高层状断块油藏水驱采收率是行之有效的。