注聚三采期岩电参数的实验

中国东部部分油田已进入三次采油期,储层注入聚合物溶液后,储层的物性、电性会发生相应的变化。为了查明储层内注入聚合物溶液后所发生的变化,模拟双河油田开发过程中设计的岩心注聚实验,通过观察注入聚合物的砂岩岩心的实验结果,得出了岩心驱替前后,岩心孔隙度和绝对渗透率变化不大、薄膜电位减小、阿尔奇公式中的孔隙度结构指数优增大,饱和度指数集中在1.4～1.7之间、电阻率变化呈“S"和斜躺“L”型减小等变化规律。注聚后孔隙度和渗透率的计算可以按常规测井评价方法进行,注聚前的薄膜电位明显大于注聚后的薄膜电位,因此注聚后在测井解释中要特别注意自然电位曲线的应用,在聚合物驱油过程中,岩心的电阻率变化规律与盐水驱油过程的电阻率相类似,故在测井评价中可直接使用水驱油田的饱和度的评价方法。     

稠油油藏热-流体-力学耦合模型研究及应用

在稠油油藏开发中,由于原油黏度高一般采用注蒸汽开采。基于连续介质力学理论,考虑了热对流的影响,建立了蒸汽注入条件下对地层压力、变形和有效应力定量评价的改进的热-流体-力学耦合数学模型;应用全隐式顺序Galerkin有限元数值解方案对注蒸汽井热-流体-力学耦合过程进行了数值模拟。计算结果表明,由于地层流体高温膨胀引起的高压力,会导致位移、变形,甚至地层结构破裂;温度对地层破裂形态的影响显著。研究表明,这个改进模型比传统模型更加准确、实用,可以用于蒸汽注入速率优化和油藏、地质、热-流动力反应、地应力水平等综合作用效应研究。     

稠油油藏蒸汽驱中后期剩余油分布特征及提高采收率方式研究

针对中国浅层及中深层稠油油藏,利用数值模拟研究方法,研究了不同稠油油藏的蒸汽驱开发规律和蒸汽驱中后期的剩余油分布特征,明确了稠油油藏蒸汽驱中后期的提高采收率方式。研究结果表明:浅层稠油油藏与中深层稠油油藏蒸汽驱的开发规律基本一致。驱替阶段生产效果好、产量高且稳定、油汽比高、含水率低;蒸汽突破后的开发阶段也是蒸汽驱开发的重要阶段,但是该阶段油汽比明显低于驱替阶段,表明该阶段蒸汽热效率明显降低。不同稠油油藏的剩余油分布特征类似,均表现出明显的垂向动用差异特征,即油层上部动用程度高,剩余油饱和度低,油层下部动用程度低,剩余油饱和度高,下部油层是剩余油挖潜的主要对象。从下到上逐层上返开发和多介质辅助是提高蒸汽驱中后期采收率的有效方式。研究结果对同类油藏开发具有重要意义。     

高温高盐高黏油藏缔合聚合物-表面活性剂二元驱技术

针对大港油田孔南地区高温、高盐、中低渗、稠油等制约化学驱提高采收率的瓶颈技术问题,以官109 1断块枣Ⅴ油组为目标油藏,在优选适合缔合聚合物和表面活性剂基础上,进行聚合物-表面活性剂二元驱技术室内实验和现场应用研究。通过室内实验优选,缔合聚合物AP P7和表面活性剂BHS 01二元体系溶液与常规体系相比,具有较好的耐温抗盐性,拓展了常规二元驱适用油藏的温度和矿化度范围;缔合聚合物经过岩心剪切后仍能够有效建立阻力系数和残余阻力系数;通过岩心驱替实验,体系能有效提高稠油油藏的采收率,拓宽了聚合物驱适用的原油黏度范围;矿场单井试注后,注入井注入压力和启动压力升高,纵向吸水剖面得到改善,说明该体系在高温高盐条件下仍能保持较高黏度,能够有效改善水油流度比,效果明显。     

Secondary hydrocarbon generation potential from heavy oil, oil sand and solid bitumen during the artificial maturation

Secondary hydrocarbon generation potentials from natural bitumen, oil sand and heavy oil, representing different residual oil accumulations, were determined by artificial maturation in a closed pyrolysis system. Simulated results indicate that their thermal behavior and reactivity are similar to those of kerogen, and that they can generate hydrocarbons once subjected to suitable geological processes. Overall differences in oil and gas generation potentials among the samples result from differences in the chemical structure of precursor components, physical compaction status, and mineral matrices. Hydrogen rich precursors, such as oil sand and heavy oil, have greater potential to generate hydrocarbons than hydrogen poor ones. Naturally compacted oil sand has slightly higher conversion efficiency than artificially compacted heavy oil as indicated by lower residual bitumen content. However, total gas and liquid oil recovery from oil sand is lower than from heavy oil due to the poor release of pyrolytic products from well compacted and cemented networks in the experiments. Mineral matrices of previous oil deposits also affect further hydrocarbon generation potential. Carbonate matrices inhibit total oil and gas generation, which consequently retains high gas potential at the postmature stage. Traditional oil generation models mainly consider the thermal alteration of kerogen; this study provides supplemental information for superimposed basins where previous oil accumulations may have been destroyed and reburied to serve as secondary sources of oil and gas. Consideration of previous oil residues as potential source rock allows better estimates of available oil resources and the risks associated with their exploration.     

Assessing the maturity of oil trapped in fluid inclusions using molecular geochemistry data and visually-determined fluorescence colours

The thermal maturity of oils extracted from inclusions and the fluorescence colours of oil-bearing fluid inclusions have been measured in 36 sandstone samples from Australasian oil fields. The inclusion oils were analysed using an off-line crushing technique followed by GC–MS. A maturity assessment was made for each inclusion oil using 25 molecular maturity ratios, including a newly defined dimethyldibenzothiophene ratio (DMDR). Each inclusion oil was placed in one of 4 maturity brackets, approximately equivalent to early, mid, peak and post oil generation windows. The fluorescence colours of oil inclusions were visually-discriminated into “blue”, “white” and “yellow plus orange” and their proportions estimated using point counting techniques. Sixteen samples have >85% of oil inclusions with blue fluorescence, whilst other samples have more variable fluorescence colours. One sample has 100% of oil inclusions with yellow plus orange fluorescence. The results show that samples containing mainly blue-fluorescing oil inclusions have thermal maturities anywhere within the oil window. In particular, the molecular geochemical data strongly suggests that oil inclusions with blue fluorescence can have relatively low maturities (calculated reflectance <0.65%), contrary to the widely applied assumption that blue fluorescence colours indicate high maturities. Samples containing mainly white-fluorescing oil inclusions have maturities anywhere within the oil window and cannot be distinguished using molecular geochemical parameters from samples containing mainly blue-fluorescing oil inclusions. Though few in number, samples with mainly yellow and orange-fluorescing oil inclusions tend to have maturities in the lower half of the oil window. The data presented strongly suggest that although the relationship between API gravity and the fluorescence properties of crude oils is well established, the extension of this relationship to the use of the fluorescence colours of oil inclusions as a qualitative thermal maturity guide is not justified. Fluorescence colour depends in the first instance on chemical composition, which is controlled not only by maturity but by several other processes. For example, inclusions in samples from below current or residual oil zones in the Timor Sea contain a high proportion of yellow- and orange-fluorescing oil inclusions compared to the overlying oil zones, which are dominated by blue-fluorescing oil inclusions. This observation is interpreted to be due to water washing causing molecular and gross fractionation of oils prior to trapping. Fractionation of the gross composition of oil during the inclusion trapping process may also be a significant controlling process on the fluorescence colours of oil inclusions, due to the preferential adsorption of polar compounds onto charged mineral surfaces. A trapping control is strongly supported by synthetic oil inclusion work. Care should be taken when interpreting the charge history of samples containing oil inclusions with mixed fluorescence colour populations, such as those from the Iagifu-7x well in the Papuan Basin. It is possible that the different colour populations represent a single oil charge, with oil inclusions trapped under slightly different conditions or at slightly different grain surfaces, rather than multiple migration events.     

极浅层稠油油藏油砂特征及潜力评价

油砂和浅层稠油是具有超低开发成本的两类非常规资源,非常规与历次油价下跌密切相关,使得这类资源成为了全球瞩目的焦点.春风油田兼具地表油砂和浅层稠油两类非常规,但岩心在地表会呈现极松散的不成型油砂,使得一些基础常规实验无法测定,影响到进一步分析评估.因此,需要针对这类非常规资源进行一系列新实验,即在常规实验的基础上,增加热物性、高温相渗、核磁共振等专项实验,并与常规实验结果进行比较.热物性实验发现,储层内部灰质、泥质夹层导热性良好,反映热波及效率会较高.相渗实验发现,油砂的油水相渗Kro和Krw的终点间距较大,两相覆盖范围宽,束缚水饱和度低,且孔隙越均匀,油相相对渗透率就越大.实验还发现,热物性、相渗、阵列感应实验得到的不同参数,相互之间存在一定相关性.利用新的核磁共振方法,可直接得到束缚水饱和度,获取原始含油饱和度,进而求取驱油效率,大大简化实验步骤和测试项目.最后,通过驱油效率计算和潜力评价发现,虽然经过多轮次吞吐,油砂目前的平均含油饱和度仍然很高,反映了稠油储量动用程度低,仍有很大的开发潜力.     

幔源CO_2充注驱油机理——以松辽盆地南部长岭凹陷为例

分析天然气(CH4)驱油、原油驱水原理,建立了幔源CO2流体的充注驱油模型,在模型中CO2能否形成足够驱动力是驱油的关键。松辽盆地南部长岭凹陷泉四段储层与该模型相符合,在储层中发现幔源CO2与油气混层现象,并且CO2充注时间晚于油气注入时间。根据研究区地质条件,对幔源CO2驱油动力和阻力以及影响其大小的参数(CO2与原油的密度、界面张力、孔喉半径和CO2柱高度)进行分析,得出幔源CO2与原油所产生的浮力足可以突破油气运移阻力(毛细管阻力)。从物理和数学的角度证明幔源成因CO2能够对油气运移起到推动作用。     

Genesis of oil: A fundamental problem of geology (the current state of the problem)

The current state of the problem of oil genesis is discussed. The biogenic (sedimentary-migration theory) of oil genesis is shown to be valid based on the analysis of present-day data on the composition and properties of oil, the composition and distribution of organic matter (OM) in sedimentary rocks, and numerous calculations of the balance of oil-and-gas generation at different stages of catagenetic evolution. The confinement of oil and gas fields to sedimentary basins, as well as the relation of oil and/or gas reserves to volumes of oil-and-gas source rocks, which occur (or occurred) in the generation center, and/or to extremely high potential of oil source formations also indicate of the relationship between oil-and-gas fields and the “life” of former geological epochs.     

超稠油油藏转小井距蒸汽驱条件及时机

蒸汽驱是稠油油藏经过蒸汽吞吐开采后进一步提高原油采收率的主要热采阶段。但不是说任何时候转驱都可取得较好的效果。笔者系统研究了影响蒸汽驱开采效果的因素：原油粘度、油层有效厚度、纯总厚度比、起始含油饱和度和油层非均质性等,确定出适宜蒸汽驱开采的油藏条件。在分析稠油油藏加密吞吐后油藏条件变化的基础上．利用油藏工程数值模拟技术研究确定出超稠油油藏转小井距蒸汽驱的合理时机。     

高岭石对稠油氧化影响的DTA-TG分析

运用NETZSCH STA 409PC同步热分析仪针对新疆克拉玛依油田红浅扩大试验区中的稠油样品在氧化过程中高岭石的影响,分析测试。研究结果表明,高岭石的加入影响了稠油的低温及高温氧化反应,使稠油的低温氧化DTA峰值温度从437.6℃增加为455.4℃;高温氧化DTA峰面积显著减小,峰值从607.8℃减小为597.8℃;高岭石含量的增加,有利于降低稠油的低温,高温氧化的DTA峰值温度。随着升温速率的增加,混合样品中稠油的低温,高温氧化及高岭石脱羟基反应呈现为动力学过程。研究结果有助于深入认识原油的氧化过程,对提高采收率和推动稠油油藏的有效开发具有重要的意义。     

整体桥高性能混凝土桩−土相互作用试验研究

高性能混凝土（高性能复合水泥基材料engineered cementitious composite,简称ECC与超高性能混凝土ultra-high performance concrete pile,简称UHPC）桩基具有良好的抗开裂性能和较高的承载能力,能较好地满足整体桥纵桥向变形。开展了砂土中高性能混凝土桩低周往复拟静力试验,得到了桩基的破坏特点、抗开裂能力以及极限承载力,分析了其桩身变形、桩侧土抗力以及桩身应变等分布规律,并与钢筋混凝土（RC）桩进行了比较。在此基础上,讨论了几种常用规范的适用性。试验结果表明,ECC、UHPC材料能有效减轻桩基的破坏程度、提高桩基的抗开裂能力以及水平承载力;相比RC桩基,高性能混凝土桩基的破坏位置更深,桩基的有效桩长更大,抗震性能更好;其中,ECC桩基的抗开裂能力最强,开裂荷载可达5.8 kN,开裂位移可达15 mm。试验结果还表明,高性能混凝土桩基的变形沿埋深方向不断的减小,埋深1.5 m以下位置基本为0;桩侧土抗力先增大后减小,桩底土抗力和变形量为0;桩身应变分布较为对称,且呈“橄榄”形,在埋深4D～6D（D为桩径）区间内桩身应变较大。分析计算表明,当桩顶位移在10 mm以内时,“m”法与API新规范法均能较好地计算高性能混凝土桩的桩身变形;当位移超过10 mm后,“m”法与实际数值相差较大。“m”法与API新规范法均不能较好地计算桩身弯矩,适用性不高;桩侧土抗力建议采用API新规范法。     

稠油热采储层非均质性及其对开发的影响——以辽河西部凹陷某试验区于楼油层为例

本文以辽河西部凹陷某试验区为例,基于7 口井岩心、镜下薄片、分析测试及400口井测井等多种资料,采取点、线、面相结合的研究思路,利用地质统计学方法,开展稠油热采储层非均质性研究。整体上,于楼油层储层非均质性较强,储层非均质性受沉积作用、成岩作用和构造作用等影响（以沉积作用为主）。单井岩电特征与层内韵律非均质性关系密切,目的层可见3种沉积韵律模式,包括正韵律、反韵律和复合韵律（其中以正韵律和复合韵律为主）。沉积微相空间上的快速变化,导致储层非均质性增强。单层之间隔层分布较稳定,隔层厚度多大于2 m。非均质性强、中、弱的区域大体呈条带状,以北西-南东向展布,与物源方向基本一致。储层非均质性直接影响到了油藏的开发效果,研究储层非均质性可为油藏开发方式的转换提供参考。     

井筒电加热改善水平井蒸汽吞吐效果机理实验

针对稠油水平井蒸汽吞吐面临入井渗流阻力大、产量水平低、吞吐递减率高、采收率偏低等问题,提出了电加热辅助水平井蒸汽吞吐方法。首先根据水平井蒸汽吞吐过程中的电加热与蒸汽复合传热特征,建立了电加热辅助蒸汽吞吐三个阶段的(注汽阶段、焖井阶段、生产阶段)储层升温解析模型,在此基础上,设计并开展了电加热辅助蒸汽吞吐和常规水平井吞吐的宏观比例物理模拟对比实验,通过实验验证了解析公式,揭示电加热改善水平井吞吐效果关键机理,并利用实际典型井模型进行了潜力预测。结果表明:电加热协同蒸汽吞吐,具有注蒸汽阶段实现水平段均匀加热升温、焖井阶段持续热补偿加热近井地带、生产阶段降低原油入井渗流阻力并提高吞吐产量的关键机理。典型井组预测电加热辅助水平井吞吐可提高吞吐采收率9.4%,油汽比从0.14提高到0.23,在水平井蒸汽吞吐油藏具有重要应用潜力。     

银额盆地哈日凹陷多类型油气藏共生特征及其成藏机理

近年来,银根—额济纳旗盆地哈日凹陷发现了多种类型油气藏,证实其有较好的油气勘探前景,但该凹陷油气地质条件极为复杂,特别是对多类型油气藏的共生特征及其成藏机理认识不足,限制了对油气分布规律的科学预测,制约了油气勘探的进程.基于对各类型油气藏的剖析,探讨多类型油气藏共生特征及其成藏机理,预测油气分布,分析勘探方向,以期为该...     

弧角型PDC钻头切削齿布齿模式仿真分析

钻头在钻进复杂非均质地层时,由于其冠部形状的限制,钻头各部位切削齿受力不均匀,局部切削齿受到较大的冲击载荷,导致钻头发生“涡动”现象。为了解决上述问题,提出“多级力平衡”的切削齿周向布齿方案,通过建立全尺寸钻头破岩有限元仿真模型,分析顺时针、逆时针以及“多级力平衡”3种周向布齿模式下切削齿及钻头的受力特性。模拟结果表明:相对于顺时针和逆时针周向布齿,“多级力平衡”布齿模式下各刀翼载荷分布比较均匀,钻头的稳定性和攻击性均得到较大改善,钻头的破岩效率提高28%以上;顺时针布齿模式下钻头的侧向力最大,其稳定性相对最差;逆时针布齿模式下钻头的钻压最大,其攻击性相对较差,并且钻头的破岩效率最低。上述研究成果能够为指导PDC钻头切削齿的周向布齿设计提供理论依据。建议今后加强“多级力平衡”周向布齿模式下切削齿载荷沿钻头径向分布规律方面的研究,以指导防涡稳定PDC钻头的优化设计。      

关于岩石导热性野外测定方法的研究

导热系数是岩石重要的物理参数之一，其在地热能开发及岩土热工程应用中有着重要意义.目前的测试方法需要将岩样采回实验室进行表面加工，运输和加工过程会破坏岩石结构和影响含水率等，不仅测试工艺复杂，而且导致测试结果不准确.本研究提出一种现场获取岩石导热系数的新方法.利用导热耦合剂填充岩石表面与探头之间的接触面，减小测试过程中的接触热阻，辅助热物性测试仪器来开展野外导热系数测试工作.通过配制不同导热硅脂与不同铜粉掺量充分混合的导热耦合剂进行对比实验，确定导热耦合剂的最优配比.实验表明，导热耦合剂的涂抹能有效地减小探头与岩石表面的接触热阻，提高测试精度，且导热耦合剂本身对岩石的导热系数影响甚微.研究成果可为野外准确便捷地获得岩石导热系数提供参考.     

Source potential and palynofacies of Late Jurassic “Lemeš facies”, Croatia

Laminated limestone and calcareous shale outcrop samples from the Late Jurassic “Leme?” facies (Croatia) were investigated to characterize their organic facies and palynofacies and their hydrocarbon generative potential. The results indicate that the organic rich sediments of “Leme?” facies were deposited within a relatively shallow marine environment at low redox potential, characterized as an oxygen depleted depositional setting with stratified bottom waters of the carbonate platform (Adriatic Carbonate Platform). The organic rich samples contain a high portion of lipid rich amorphous kerogen of algal/phytoplankton origin, enriched by bacterial biomass. Most of the analyzed samples have total organic carbon contents (TOC) greater than 3%, Rock-Eval S2 >20 mg HC/g rock, yielding Hydrogen Index (HI) values ranging from 509–602 mg HC/g TOC. According to these results, the analyzed samples have very good to excellent oil generative potential. Relatively high sulfur content suggests that the kerogen is best described as Type II-S. Biomarker maturity parameters, as well as the fluorescence of the isolated kerogen, show that the organic matter is at early to peak oil thermal maturity. The observed level of thermal maturity indicates that these samples were once buried to depths of ～5.5–5.8 km before being uplifted in the late Tertiary. The surface outcrops of the “Leme?” facies suggest that these strata have significant source potential and are the likely source of oil in the Croatian External Dinarides.     

琼东南盆地深水区天然气运移规律与成藏组合

为解决琼东南盆地深水区新区天然气勘探中遇到的天然气运移认识不清的难题,在实验（数值）模拟和大量调研基础上,综合钻井、构造和地震等资料,利用盆地模拟软件,开展了深水区天然气运移规律系统研究。结果显示,深水区天然气运移主要受到“流体势场” —“通道场（输导体系格架）”—“约束场（区域盖层）”3场耦合的控制。高势生烃凹陷内的底辟带和晚期活化沟通气源断裂发育区的陵水组区域盖层完整性被破坏,天然气垂向运移为主,利于在区域盖层之上形成多个中小规模气藏组成的浅层大中型岩性型气田;部分凹陷边缘—低凸起及之上地区陵水组区域盖层保存完整,断裂—砂体—构造脊汇聚型复合输导体系发育,天然气运移侧向为主,利于在区域盖层之下形成深层整装构造型大中型气田,而新构造运动是深水区晚期大中型气田形成的重要诱因。深水区最终形成了浅层和深层两套成藏体系和3套有利成藏组合。成果指导勘探,在松南低凸起深层成藏组合勘探中首次获得突破性发现,继续拓展,有望在中央峡谷外找到新的大中型气田群。