Rheological study of methane gas hydrates in the presence of micron-sized sand particles

Natural gas hydrates,intricate crystalline structures formed by water molecules and small gas molecules,have emerged as a significant and globally impactful clean energy resource.However,their commercial exploitation faces challenges,particularly operational disruptions caused by sand-related blockages.Understanding the rheological properties of hydrate slurry,especially in the presence of micron-sized sand particles,is imperative for ensuring the flow assurance of subsea hydrate exploitation.This study extensively investigates the rheological properties of sand-containing hydrate slurries.The findings reveal that these slurries exhibit non-Newtonian fluid characteristics,including yield stress,thixotropy,and shear-thinning behavior.Solid-like elastic features are observed in sand-containing hydrate slurries before yielding,transitioning to viscous behavior after yielding.Even with a minimal amount of sand,both static yield stress and yield strain experience substantial changes,correlating with the increase in sand concentration.The research conclusively establishes the thixotropic nature of sand-hydrate slurries,where the viscosity decay rate is directly influenced by the shear rate.These insights aim to contribute comprehensively to the development of effective flow assurance strategies,ensuring the safe and stable operation of subsea hydrate exploitation.

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East Africa.We characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic data.We find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single lobes.When the topography is irregular and presents topographic lows,lobe complexes first infill these depressions.Single lobes are deposited preferentially at positions with higher longitudinal(i.e.across-slope)slope gradients.As the longitudinal slope becomes higher,the aspect ratio of the single lobes increases.Lateral(i.e.along-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single lobes.When the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap surface.Furthermore,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,i.e.sediments tend to accumulate vertically.The results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

东非鲁伍马盆地深水X气藏海底扇储层构型研究:重力流—底流交互作用的指示意义

底流在陆缘深水环境下广泛存在,可对深水沉积过程及砂体分布产生重要影响。前人对重力流与底流的交互作用机制及沉积产物开展了大量研究,但目前有关底流改造型的海底扇储层构型模式仍然研究不够深入。东非鲁伍马盆地是当前重力流—底流交互作用研究的热点地区,文中以其代表性的下始新统海底扇水道体系为例,综合岩心、测井及三维地震资料开展储层构型精细表征,建立重力流—底流交互作用下的海底扇水道体系构型模式。研究表明,目标水道体系内部发育水道、溢岸及朵叶3种构型要素,其中水道可分为水道复合体、单一水道及其内部不同级次的构型单元。底流对细粒物质的搬运可形成非对称的溢岸沉积,导致水道复合体之间呈逆底流侧向迁移叠置样式,其间泥岩隔层容易保存;单一水道之间呈顺水道纵向迁移或逆底流侧向迁移样式,其中纵向迁移部位水道切叠连通,而侧向迁移部位容易保存泥质侧向隔挡体。受重力流沉积演化的影响,单一水道内部充填由砂泥交互型逐渐演化为富砂型,且在水道弯曲段的轴部砂体最为发育。

“Dual Carbon”Game and Countermeasures under Carbon Politics

Carbon politics is quietly emerging,and countries around the world are divided into three categories.Western developed countries consuming clean energy are classified as the first category.Energy-importing developing countries are included in the second category,and resource-rich countries relying on fossil fuel export are sorted as the third category.Countries of the“three categories”have already and will continue to play games over“dual carbon”round after round.The goal of Western countries’carbon politics is to continue to lead the world,stay ahead,and use their advantage of low emission to extract carbon benefits.Energy-importing developing countries face threats and opportunities.Resource-rich countries are unable to tackle the situation without aggravating another problem.China should narrow its gap in the new energy industry with Western developed countries,continue to promote natural gas pipeline construction to ensure energy security,control the pace to realize the“dual carbon”goal,and strive for its own legitimate rights and interests.

谈钻井井喷失控事故的防范与处置

井喷失控是油气钻井过程中的灾难性事故,因此杜绝井喷失控事故的发生是安全钻井的最高目标和最低要求。本文对中国石油天然气集团公司在2006年以前所发生的59井次典型钻井井喷失控案例进行分析统计,发现在钻进与提下钻期间发生的就有53井次,进一步找出与这53井次井喷失控事故关联频次最高的单一要素及其要素组合,并结合当前对井喷失控事故的处置方法与经验提出了井喷失控事故的日常防范和应急处置的要点,力求为安全钻井和科学钻井提供有效的防范方法及高效的处置措施。

分层注水技术在中亚RN非均质碳酸盐岩油田的应用

RN油田是中石油海外经营开采最早的、中亚规模较大的碳酸盐岩油藏。油田自然递减率高,主力油藏地层压力保持水平低,纵向动用程度不高,层间矛盾大。结合油田实际情况,研究了3种分层注水技术——液力投捞分层注水、同心双管分层注水、桥式偏心分层注水技术。现场应用表明,桥式偏心分层注水和同心双管分注技术应用效果显著,液力投捞分注技术不适用于该油田。该研究对海外碳酸盐岩油田开发具有重要指导意义。

跨国油公司油气资产类型划分及投资机会预测

跨国油公司具有相关多元化特征,其每一个海外资产区构成一个自主经营的利润中心。根据资产利润占公司年度总利润的百分比,以及该资产的产量增长率,建立资产结构矩阵。应用该矩阵可以将油气资产划分为四种基本类型,因不同类型资产对公司的资金需求、利润贡献和未来发展的影响存在明显差异,因此要通过资产类型科学配置,在不同资产区之间形成强势现金流差动,以保持公司持续盈利。另一方面,基于资产矩阵的单项资产成长轨迹研究揭示,油气资产一般具有四种成长轨迹类型,不同类型轨迹具有不同的投资机会点,因而可应用于投资机会预测和公司资产经营动态监测和管理。

让纳若尔低渗透油田水平井分段酸压工艺研究及应用

让纳若尔油田Д南低渗透难动用储量近3 000万t,但由于储层薄、物性差、地层压力低等特征,直井难以实现经济开采,水平井产能低。通过引入以水平井分段改造为主导的完井、酸压、气举排液投产一体化技术,形成了分段段数优选、裂缝参数优化、遇油膨胀封隔器+滑套分段完井配套、液氮前置注入及深度酸压和气举排液、采油一体化技术。现场应用结果表明,该工艺有效扩大了水平井控油区域,改善了储层导流能力,缩短了酸压后排液时间,提高了单井产能。水平井分段酸压配套技术的应用实现了该区域储量的有效动用,对中石油海外低渗透难动用储量高效开发具有重要指导意义。

聚驱井含水率特征曲线在示踪剂综合解释技术中的应用

为了解示踪剂注剂井组中未见剂井的井间参数特征,利用示踪剂综合解释技术对其进行了注采井井间储层参数综合解释;结合聚合物驱单井含水率变化特征曲线和指纹图谱相似度计算方法进行了未见剂井与见剂井的相似度计算。结果表明,注聚合物后见效井的含水率曲线下降漏斗的数目反映了优势通道的数目,见效时间的快慢在一定程度上说明最优通道渗透率的大小,见效有效期反映了地下聚驱波及的体积;综合评价结果能够初步判断未见剂井是否存在优势通道以及发育状况。利用聚驱井含水率特征曲线对见剂井与未见剂井进行相似度计算,不仅节省了示踪剂监测费用,扩展了示踪剂综合解释结果的内容,同时也为油田开发调整提供了指导和依据。

缅甸PSC-101井高密度钻井液技术

PSC-101井位于缅甸PYAY油田,该油田地质情况复杂,地层压力系数高、气层活跃、地层造浆严重。根据地层特点和对钻井液技术难点的分析,在该井的一开、二开井段使用PAC141钻井液体系,三开和四开井段使用两性离子聚磺钾盐钻井液体系。现场应用表明:两性离子聚磺钾盐钻井液体系抗温性能、抑制性能好,各项性能可控,固相容量限高,可加重至2.3 g/cm3,基本上可以满足缅甸PYAY油田的钻井需要;且工艺简单,操作方便。对钻井液施工过程中存在的问题也进行了探讨。

海外低勘探程度地区勘探技术与应用

在海外地震测网稀或不规则、钻井少甚至没有钻井资料且地质构造复杂的所谓低勘探程度地区进行风险勘探,其并不十分明朗的勘探前景为我们提供机遇的同时也提出了挑战。本文在深入研究的基础上,总结出了一套适用于低勘探程度地区的勘探技术。其主要内容包括确定盆地的主力凹陷、确定盆地的主力勘探层系和成藏组合、选择有利构造带和规模目标等,形成了一套以规模目标为核心的定量—半定量评价标准及成熟的工作流程。将这套技术应用于海外B盆地的油气勘探中,取得了很好效果。

Oil & Gas Resources and Cooperation Opportunities on the “Ice Silk Road”

Ice Silk Road contains abundant oil and gas sources.The total amount of oil and gas resources found alongside the Arctic region covered by Russia totalled 290 billion barrels of oil equivalent,which takes up 88.2%of the total volume discovered in the Arctic region.Eleven large oil and gas fields containing more than 5 billion barrels of oil equivalent have been discovered alongside the ice silk road,10 of which are in the West Siberian Basin;54 large oil and gas fields containing 0.5-5 billion barrels of oil equivalent have been discovered,43 of which are in Russia.

石油钻井机械设备维护与保养措施

在石油勘探开发过程中,钻井机械设备的维护与保养日益重要。设备过早的损坏或者机械故障的产生,不仅影响设备的使用寿命,还会影响钻井作业的稳定运行,造成一定程度的经济损失。基于此,文章从钻井机械设备维护与保养的重要性入手,探讨钻井机械设备常见故障发生的原因,在此基础上,提出钻井机械设备维护与保养的有效措施,使机械设备在实际工作中更好地发挥效用。

基于供应链模式的石油企业物资供应管理策略

石油钻探企业发展的主要问题集中在石油勘探过程中以及物资供应管理方面,即在石油钻探以及物资供应中的成本投入较大,很可能造成企业资金链断裂的问题。资金问题也是制约企业生存和发展的关键性问题。因此,要想促进石油钻探企业的良性发展,则应加强对物资供应管理工作的重视,采取有效管理手段达成成本控制的目标,并且保障物资及时有效供应。供应链模式属于企业物资管理工作中的常见管理模式,在各个行业及领域中均发挥了较好的管理作用。文章基于供应链模式下的物资供应管理策略展开研究,以期能够增强石油钻探企业的物资管理水平。

Genetic mechanism and development of the unsteady Sarvak play of the Azadegan oil field,southwest of Iran

The upper Cretaceous Sarvak reservoir in the Azadegan oil field of southwest Iran has its oil–water contact nearly horizontal from the north to the center and dips steeply from the center to the south.The purpose of this paper is to interpret this abnormal reservoir feature by examining the accumulation elements,characteristics,and evolution based on the 3D seismic,coring,and well logging data.Generally,in the field,the Sarvak reservoir is massive and vertically heterogeneous,and impermeable interlayers are rare.The distribution of petrophysical properties is mainly dominated by the depositional paleogeomorphology and degrades from north to south laterally.The source is the lower Cretaceous Kazhdumi Formation of the eastern Dezful sag,and the seal is the muddy dense limestone of the Cenozoic Gurpi and Pebdeh Formations.Combined with the trap evolution,the accumulation evolution can be summarized as follows： the Sarvak play became a paleo-anticlinal trap in the Alpine tectonic activity after the late Cretaceous（96 Ma） and then was relatively peaceful in the later long geologic period.The Kazhdumi Formation entered in the oil window at the early Miocene（12–10 Ma） and charged the Sarvak bed,thus forming the paleo-reservoir.Impacted by the ZagrosOrogeny,the paleo-reservoir trap experienced a strong secondary deformation in the late Pliocene（4 Ma）,which shows as the paleo-trap shrank dramatically and the prelow southern area uplifted and formed a new secondary anticline trap,hence evolving to the current two structural highs with the south point（secondary trap） higher than the north（paleo-trap）.The trap deformation broke the paleoreservoir kinetic equilibrium and caused the secondary reservoir adjustment.The upper seal prevented vertical oil dissipation,and thus,the migration is mainly in interior Sarvak bed from northern paleo-reservoir to the southern secondary trap.The strong reservoir heterogeneity and the degradation trend of reservoir properties along migration path（north to south） made the reservoir readjustment extremely slow,plus the short and insufficient re-balance time,making the Sarvak form an ‘‘unsteady reservoir＇＇which is still in the readjustment process and has not reached a new balance state.The current abnormal oil–water contact versus the trap evolutionary trend indicates the secondary readjustment is still in its early stage and has only impacted part of paleo-reservoir.Consequently,not all of the reservoir is dominated by the current structure,and some parts still stay at the paleo-reservoir form.From the overview above,we suggest the following for the future development： In the northern structural high,the field development should be focused on the original paleoreservoir zone.In the southern structural high,compared with the secondary reservoir of the Sarvak with the tilted oil–water contact and huge geologic uncertainty,the lower sandstone reservoirs are more reliable and could be developed first,and then the deployment optimized of the upper Sarvak after obtaining sufficient geological data.By the hints of the similar reservoir characteristics and tectonic inheritance with Sarvak,the lower Cretaceous Fahliyancarbonate reservoir is also proved to be an unsteady reservoir with a tilted oil–water contact.

一种企业员工绩效的不确定性评估方法

在企业的发展与成长中,对于企业员工的绩效评估是一个基础的问题。该文提出一种具有不确定性的定性评估方法,该方法基于云模型在定性概念和定量数据之间进行不确定性转换的桥梁作用,根据实际问卷调查得到的评估数据,利用逆向云算法生成绩效评价特征向量,得到评价云图。该方法较好地解决了传统定量评估方法存在对数据硬性划分的问题,也克服了基于模糊数学的定性评估方法中的隶属度定义主观性强、缺乏定量分析等不足。并以某上市公司的员工绩效评估为实例,验证了方法的有效性,为企业员工绩效评价提供了新的方法。

谈钻井井控的安全文化与现场实践

钻井井控是钻井安全的核心,关乎钻探企业的生存与发展。在油气勘探与开发的钻井实践中,钻井井控形成了一系列井控安全的理念、观念、原则,法律法规、规章制度,并养成了一系列良好的行为习惯,体现了文化引领、技术支撑和行为约束的企业文化管控目标,积累了大井控、班自为战、专家支持等一系列实战经验,为实现井控安全提供了有效保障。

Positive Correlation between Sino-Russian Oil and Gas Cooperation and 'Russian Leverage'

It is well known that since the disintegration of the former Soviet Union, Russia has suffered detrimentally as a result of strategic pressure from the United States and Europe. After over ten years of concession and silence,Russia with Putin as the core counterattacks, deploying stunning tactics one after the other. These not only set up'loss limits',but also protected and won Russia's interests to the greatest extent, such that Russia not only won respect but also gained benefits. These stunning tactics are called'Russian Leverage'.

强化应急管理 为企业实施国际化战略保驾护航

2008年11月,中国石油天然气集团公司应急协调办公室组织考察小组对挪威国家石油海德鲁公司、挪威联合搜救中心、国际SOS组织、英国化险咨询公司的应急管理工作、预案体系建设、应急指挥场所和平台建设等情况进行了调研考察。在考察中,感受到应急工作受到越来越多的关注和重视,所考察企业应急组织体系完善、现代化程度较高,并依靠先进的技术和装备不断提高应急处置和救援能力,同时还注重提高应急预案的实用性和基层员工的应急综合能力。为此,建议我国石油企业在应急管理工作中,加强应急平台的功能化建设,完善应急组织体系、预案体系建设,加强应急物资装备管理,加强应急专家和救援队伍建设,加强与国际专业化公司的业务合作与交流。

钻井井控安全的风险因素与技术对策

随着勘探开发由常规钻井向“三高两浅”井、页岩油–页岩气的大位移水平井和山前构造深井、超深井等高难度钻井领域转移,钻井井控的风险等级、管控难度和技术要求也随之大幅度提高。为进一步突出钻井安全生产中的井控安全这个核心,本文系统分析了钻井井控安全的发展现状、风险因素及其技术对策,是钻井井控实施精细管理、升级管理、创新管理、科学管理,进而迈向文化管理的战略思考和积极实践。