沙湾组油气地质特征与勘探实践

准噶尔盆地沙湾组以岩性油气藏为主,存在油砂体规模较小、油层薄、储层岩性变化快等勘探难题。2005年,排2井在沙湾组钻遇油层,日产油49.6 t,地面原油粘度为1.6 mPa.s。立足实践、大胆开拓促成了沙湾组浅层、稀油、高产岩性油藏的突破,高精度三维地震技术发挥了关键作用。车排子地区具有多油源输导、多层系含油、多类型富集、多品位共存的复式聚集特点和"三层楼"油气成藏模式。沙湾组轻质油藏油砂体形态与振幅属性具有较好的对应关系,能够通过地震属性有效识别油水边界。稀油油浸为含油性下限,粉细砂岩为岩性下限,渗透率0.022μm2、孔隙度20%为物性下限,油层声波时差大于300μs/m,电阻率大于1.5Ω.m,电阻增大率大于5.5。已发现沙湾组油藏23个。     

低渗油藏裸眼水平井压裂技术及应用

针对大庆外围朝长地区未动用储量属于低渗透扶余油层,采用常规直井开发,单井产能低、开发效益差,为进一步提高低渗透扶余油层开发效果,通过水平井近平衡钻井、裸眼完井,减少了钻井及固井对储层污染,采用打孔管结合油膨胀封隔器工艺进行压裂改造,探索低产低渗透储层有效的开发途径。试油及投产效果表明,低渗透油藏采用近平衡钻井、裸眼完井能有效地保护储层,实施裸眼水平井储层压裂改造能够提高单井日产油,对进一步改善低渗透油藏开发效果有重要意义。     

靖边席麻湾延9段油气富集规律研究

近年来,延长股份有限公司对靖边采油厂西南部席麻湾开始进行系统的勘探和开发,在该区域钻探过程中,发现延9段油气显示比较明显,并且部分井试油获得了较好的工业油流,充分说明了研究区有良好的勘探开发前景。通过基础地质研究分析油藏特征、油气成藏地质条件及油气富集规律,为油田进一步开发提供可靠依据。     

广饶潜山油气成藏条件分析

草桥-广饶潜山部署钻探了草古125、草古126井均获成功。其中草古125井获日油29．98t，草古126井获日油33.3t工业油流，发现了济阳坳陷目前产层埋深最浅的油藏，展示了广饶地区古潜山油藏将是油田下一步重要的重要产能接替阵地。     

中美页岩气成藏条件、分布特征差异研究与启示

美国页岩气大多为海相热成因型,产气页岩主要分布在前陆和克拉通盆地的泥盆—石炭系,埋藏深度一般为1 500～3 500 m。我国页岩分为海相、海陆过渡相与煤系、湖相三类,其中海相页岩主要发育在坳拉槽和克拉通盆地的下古生界,富有机质集中段分布稳定,热成熟度偏高,有较高的含气量,勘探前景最好;海陆过渡相与煤系页岩主要发育在大型坳陷和前陆盆地,层系以石炭系—侏罗系为主,没有明显的富有机质集中段,含气量差别较大,勘探潜力有待落实;湖相页岩主要发育在中、新生代陆相盆地,富有机质集中段厚度大,成熟度较高的凹陷中心区可能具有一定资源前景。预测我国页岩气勘探将经历较长的探索期,未来年产量可达500亿～600亿m3规模。     

解决稠油井测试抽汲难题的探讨

在油气田勘探开发过程中，对地层进行测试，可以取得地层的产量及压力资料，对资料进行分析解释，取得地层参数，从而为油气田的后序开发提供可靠依据。我们在粘度不高的产稀油井、产水井、产气井的试油测试工具工艺配套技术研究及应用中，已经取得较大的进展，现有的工艺技术基本上能够满足生产的需求。但在稠油井的测试抽汲中，还存在着很多难题。地层测试中，抽汲效率的高低直接影响着试油产量及试油资料的优质率，影响着油气井产能的确定及油气田开发方案的制定。本文针对因原油粘度高，密度大造成油稠井测试抽汲困难，效率低下的问题，从分析稠油物性人手，针对杜75井现场测试中应用的一套适合稠油井测试工具、管柱结构和工作制度的测试工艺技术，介绍了施工过程中所采取的一系列应对措施。这些措施在一定程度上解决了稠油测试抽汲及资料录取过程中的瓶颈问题，缩短了稠油井的试油周期，为以后的稠油井试油测试提供了可靠的技术支持。     

靖边两部延长组长7、长8段油气富集规律研究

延长股份有限公司靖边采油厂自2010年以来，在靖边话部区域钻探下组合的过程中，不断发现长7、长8油层组油气姓示明显，并且部分井试油获得了较好的工业油流，充分说明研究区长7、长8具有很好的勘探开发潜力。但是由于靖边采油厂对下组合长7段、长8段开始钻探时间晚，对其油气富集规律认识不清，介于此种情况，开展靖边西部区域下组合油气富集规律研究势在必行。     

电成像测井在X6井中的应用

X6井电成像测井测量地层为石炭系和二叠系地层,录井见到良好油气显示,石炭系地层岩性为凝灰岩,二叠系地层岩性为泥岩、砂质泥岩、灰质／白云质泥岩等,均为裂缝性储层。本文论述了电成像测井在X6井石炭系、二叠系地层中有效识别裂缝、确定裂缝发育层段及裂缝参数定量计算中的应用,分析了地层溶蚀情况,确定了该区的地应力方向,研究了X6井井旁构造,在X6井的测井综合评价和地质应用中发挥了重要作用。     

陈官庄地区沙四段油气聚集规律研究

针对针对陈官庄地区沙四段滚动勘探程度低的特点,本文在对该区沙四段油源条件、储集层分布、构造及圈闭条件、断层及断层活动、异常压力研究等,确定了该区成藏模式及成藏规律,为下步该区滚动勘探部署提供了依据。     

油水同层储层井试油工艺技术优化探析

勘探研究领域中,油水同层储层井试油过程变得越来越复杂。本文基于对油水同层储层井的基本研究,针对油水同层储层井难定性的问题,进行了油水同层井油水关系影响因素探讨,并认知各因素影响特征。根据油水同层井两相流的渗流特征,为了准确界定储层油水边界,应充分考虑影响因素的多样性,进行优势互补,以利用合适的完井技术、优化试油工艺,使试油结论无法与测井解释相符合,从而实现控水增油目标,最终达到勘探目的。     

中国火山岩油气藏控制因素及分布规律

中国沉积盆地内主要发育石炭—二叠系、侏罗—白垩系和古近—新近系3套火山岩,火山岩大面积分布,烃源岩与火山岩伴生,形成良好的生储盖组合。东部盆地以中酸性岩为主,主要发育原生型火山岩储层;西部盆地以中基性岩为主,主要发育风化壳型储层,火山岩风化壳储层物性好于原生型储层物性,各种岩性、岩相均能形成有效储层。东部盆地主要发育岩性、断层—岩性油气藏;西部盆地主要发育地层型、构造—地层型、构造—岩性—地层复合型油气藏。松辽盆地深层持续沉降型断陷控制天然气区域分布,生烃断槽控制断陷内天然气分布,近邻生烃断槽的断裂构造带是天然气富集区带,优质火山岩储层控制天然气富集;新疆北部石炭系残留生烃凹陷控制油气平面分布,风化壳规模控制油气富集程度和规模,风化壳地层型有效圈闭控制油气成藏,正向构造背景控制油气运聚。指出中国火山岩有利勘探面积36万km2,预测火山岩中总资源量60亿t油当量以上,勘探潜力大。     

A new model for atmospheric oxygen over Phanerozoic time

A mathematical model has been constructed that enables calculation of the level of atmospheric O2 over the past 570 my from rates of burial and weathering of organic carbon (C) and pyrite sulfur (S). Burial rates as a function of time are calculated from an assumed constant worldwide clastic sedimentation rate and the relative abundance, and C and S contents, of the three rock types: marine sandstones and shales, coal basin sediments, and other non-marine clastics (red beds, arkoses). By our model, values of O2 versus time, using a constant total sedimentation rate, agree with those for variable sedimentation derived from present-day rock abundances and estimates of erosional losses since deposition. This agreement is the result of our reliance on the idea that any increase in total worldwide sediment burial, with consequently faster burial of C and S and greater O2 production, must be accompanied by a corresponding increase in erosion and increased exposure of C and S on the continents to O2 consumption via weathering. It is the redistribution of sediment between the three different rock types, and not total sedimentation rate, that is important in O2 control. To add stability to the system, negative feedback against excessive O2 fluctuation was provided in the modeling by the geologically reasonable assignment of higher weathering rates to younger rocks, resulting in rapid recycling of C and S. We did not use direct O2 negative feedback on either weathering of C and S or burial of C because weathering rates are assumed to be limited by uplift and erosion, and the burial rate of C limited by the rate of sediment deposition. The latter assumption is the result of modern sediment studies which show that marine organic matter burial occurs mainly in oxygenated shallow water and is limited by the rate of supply of nutrients to the oceans by rivers. Results of the modeling indicate that atmospheric O2 probably has varied appreciably over Phanerozoic time. During the Late Carboniferous and Permian periods O2 was higher than previously because of the rise of vascular land plants and the widespread burial of organic matter in vast coal swamps. A large decrease in O2 during the Late Permian was due probably to the drying-up of the coal swamps and deposition of a large proportion of total sediment in C and S-free continental red beds. Sensitivity study shows that major parameters affecting results are the mean C concentration in coal basins and the relative sizes of the reservoirs of young (rapidly recycled) versus old rocks. Less sensitivity was found for changes over time in total land area undergoing weathering and the use of direct O2 negative feedback on marine carbon burial. Good agreement for rates of C burial calculated via our model and via independent models, which are based on the use of stable carbon isotopes, indicates that the dominant factor that has brought about changes in atmospheric O2 level (and the isotopic composition of dissolved inorganic carbon in seawater) over Phanerozoic time is sedimentation and not weathering or higher temperature phenomena such as basalt-seawater reaction.     

基于岩石物理测试模型的测井曲线校正方法

针对密度测井、纵波速度和横波速度曲线探测深度较浅，受井眼不规则影响比较严重的问题，为研究储层各属性的影响及与弹性属性间的关系，采用岩石物理模型对测井资料进行诊断和校正，提高测井曲线与地层信息的匹配程度。结果表明：经过岩石物理模型诊断和校正的测井资料能明显的提高测井资料的品质，根据校正后的资料才能正确的标定井震之间的关系，为地震解释和反演提供可靠的依据。     

中国低渗透油气的现状与未来

中国低渗透油气资源丰富,具有很大的勘探开发潜力.近20年来,在低渗透砂岩、海相碳酸盐岩、火山岩勘探方面取得了很大发现,形成了国际一流的开发配套技术,实现了低渗透油气藏的规模有效开发,低渗透油气产量持续上升,其在产量构成中所占比例逐年增加.无论从近几年新增探明储量还是从剩余油气资源量看,低渗透油气都是今后勘探开发的主要对象,低渗透油气是中国未来油气工业的勘探开发主流,对保障国家能源安全具有重要的战略意义.     

福建政和上山岗金银矿床地质特征

福建政和上山岗金银矿床位于闽西北隆起带与闽东火山断坳带交接部位,金银矿体主要赋存于石英脉中,围岩为多屑凝灰岩、岩屑晶屑凝灰岩等,矿体与围岩界限清晰。矿区内构造发育,其中北东向断裂构造是最重要的导矿和容矿构造;北西向断裂为成矿后期构造,是主要的切割破坏矿体构造。     

自主创新与古生代油气田的发现

1984年在塔里木盆地部署的沙参2井实现了中国古生代海相油气田首次重大突破，成为我国油气勘探史上的重要里程碑，之后又发现多个古生代油气田及塔河大油田，并创立古生代海相成油理论。这一过程充分体现了自主创新的过程，对其进行较系统的总结，对当前和今后古生界油气勘探有重要指导意义。     

A comparative study on indirect determination of degree of weathering of granites from some physical and strength parameters by two soft computing techniques

Weathering has several adverse effects on the physical, mechanical and deformation characteristics of rock. However, when determining the weathering degree of rocks, some difficulties are encountered. Ideally, the weathering degree can be determined by simple test results and reliable prediction models. Considering this situation, the purpose of the present study is to construct simple and low cost weathering degree prediction models with two soft computing techniques, artificial neural networks and fuzzy inference systems. When developing these models, model results were tested against data from specimens collected from the Harsit granitoid (NE Turkey) and data published in the literature. Model inputs are porosity, P-wave velocity and uniaxial compressive strength, and model output is weathering degree. The models developed in this study exhibited high prediction performances when checked by train and test data sets. This result shows that the models developed herein can be used for indirect determination of weathering degree. The artificial neural network model requests numerical data as the input, while the fuzzy inference system model can take numerical data and expert opinion as the input. As a conclusion, the models have a high potential when determining weathering degree of a rock for various purposes.     

云冈石窟砂岩微观风化特征研究

云冈石窟周边岩石风化严重,岩石风化引发了多种文物病害,对云冈石窟的文物价值造成严重破坏。岩石主要成分微斜长石与H2O反应生成高岭石,岩石碳酸盐胶结物与空气中的SO2、CO2、H2O等发生化学反应,生成石膏、水碳镁石及球碳镁石等,降低了矿物颗粒间的结合强度,最终致使砂岩结构疏松。通过SEM与XRD等分析对比不同风化程度砂岩的特征,探讨了化学风化对岩石微观特征的影响。     

川东北元坝地区长兴组大型生物礁滩体岩性气藏储层精细刻画技术及勘探实效分析

以井-震精确标定为基础,借助地质-地球物理建模技术,建立了长兴组生物礁滩体岩性相—测井相—地震相—属性相—储层相(沉积微相)之间精确对应关系。在此基础上,利用地震敏感属性提取及反演方法,精细刻画了礁滩体沉积微相空间展布形态,并结合伽马测井约束的波阻抗孔隙度反演技术对礁滩体储层物性空间分布进行预测。通过与已有钻孔比对,发现储层预测效果不仅与勘探实际相吻合,且具有较高的预测精度。由此认为,地质与地球物理互动反馈的储层预测方法不仅对元坝地区生物礁滩气藏勘探具有理论性指导意义,而且对其他地区礁滩隐蔽油气藏的勘探具有实际性借鉴意义。     

Influence of mesostasis in volcanic rocks on the alkali-aggregate reaction

Mesostasis material present in the interstices of volcanic rocks is the main cause of the alkali-aggregate reaction (AAR) in concretes made with these rock aggregates. Mesostasis often is referred to as volcanic glass, because it has amorphous features when analyzed by optical microscopy. However, this study demonstrates that mesostasis in the interstitials of volcanic rocks most often consists of micro to cryptocrystalline mineral phases of quartz, feldspars, and clays. Mesostasis has been identified as having different characteristics, and, thus, this new characterization calls for a re-evaluation of their influence on the reactivity of the volcanic rocks. The main purpose of this study is to correlate the characteristics of mesostasis with the AAR in mortar bars containing basalts and rhyolites.