下扬子地区下志留统风暴沉积特征及风暴作用对泥页岩品质的影响

近年来在下扬子地区页岩气地质调查井所获取的地层岩心资料，揭示该地区下志留统风暴沉积较为发育。基于精细的岩心观察描述，详细分析了下扬子地区下志留统高家边组下段中上部风暴沉积的特征，并阐明了风暴作用对泥页岩的影响。研究表明：研究区风暴岩岩性偏细，以粉砂岩为主，石英含量较高，结构成熟度较低，具2种不同的粒度概率曲线；主要发育底部冲刷面、块状层理、平行层理、丘状交错层理、波纹交错层理、准同生变形构造等沉积构造；垂向上主要识别出4种风暴沉积序列，均具有从底到顶粒度变细的沉积特征，不同的沉积序列与风暴流能量的强弱有关。下扬子地区早志留世频繁的风暴活动与研究区的古地理背景和古气候条件具有内在联系。特大型风暴对浅海陆棚深水区的细粒泥质沉积物特征产生重要影响，包括降低有机质含量、减少单层厚度、破坏垂向连续性、改变原始沉积构造和侧向稳定性等，总体上降低了泥页岩的品质。因此，研究认为在页岩气的勘探和评价过程中应重视风暴因素对陆棚深水区原始泥质沉积物的影响。     

A comparison study into low leak rate buoyant gas dispersion in a small fuel cell enclosure using plain and louvre vent passive ventilation schemes

Hydrogen, producing electricity in fuel cells, is a versatile energy source, but with risks associated with flammability. Fuel cells use enclosures for protection which need ventilating to remove hydrogen emitted during normal operation or from supply system leaks. Passive ventilation, using buoyancy driven flow is preferred to mechanical systems. Performance depends upon vent design, size, shape, position and number. Vents are usually plain rectangular openings, but environmentally situated enclosures use louvres for protection. The effect of louvres on passive ventilation is not clear and has therefore been examined in this paper. Comparison ‘same opening area’ louvre and plain vent tests were undertaken using a 0.144 m³ enclosure with opposing upper and lower vents and helium leaking from a 4 mm nozzle on the base at rates from 1 to 10 lpm, simulating a hydrogen leak. Louvres increased stratified level helium concentrations by typically in excess of 15%. The empirical data obtained was also used in a validation exercise with a SolidWorks: Flow Simulation CFD model, which provided a good qualitative representation of flow behaviour and close empirical data correlations.     

RESERVOIR PROPERTIES OF BARREMIAN – APTIAN URGONIAN LIMESTONES,SE FRANCE,PART 1: INFLUENCE OF STRUCTURAL HISTORY ON POROSITY-PERMEABILITY VARIATIONS

Upper Barremian – Lower Aptian inner platform “Urgonian” limestones in the Mont de Vaucluse region, SE France, consist of alternating metre-scale microporous and tight intervals. This paper focuses on the influence of structural deformation on the reservoir properties of the Urgonian limestone succession in a study area near the town of Rustrel. Petrographic, petrophysical and structural data were recovered from five fully-cored boreholes, from the walls of a 100 m long underground tunnel, and from a 50 m long transect at a nearby outcrop. The data allowed reservoir property variations in the Urgonian limestones to be studied from core to reservoir scale. Eleven Reservoir Rock Types (RRTs) were identified based on petrographic features (texture, grain size), reservoir properties (porosity, permeability), and the frequency of structural discontinuities such as fractures, faults and stylolites. Tight and microporous reservoir rock types were distinguished. Tight reservoir rock types were characterised by early cementation of intergranular pore spaces and by the presence of frequent structural discontinuities. By contrast microporous reservoir rock types contained preserved intragranular microporosity and matrix permeability, but had very few structural discontinuities. Observed vertical alternations of microporous and tight rock types are interpreted to have been controlled by the early diagenesis of the Urgonian carbonates. Deformation associated with regional-scale tectonic phases, including Albian – Cenomanian “Durancian” uplift (∼105 to 96 Ma) and Pyrenean compression (∼55 to 25 Ma), resulted in the modification of the initial petrophysical properties of the Urgonian limestones. An early diagenetic imprint conditioned both the intensity of structural deformations and the associated circulations of diagenetic and meteoric fluids. Evolution of the Reservoir Rock Types is therefore linked both to the depositional conditions and to subsequent phases of structural deformation.     

Preparation of composite cathode material by using the extracted lead (Pb) of waste lead acid battery for LT-SOFC

The extraction of Pb from the waste lead acid batteries offers the conservation of energy resources and reduction of pollution load in the environment. The recycling of waste lead acid batteries than discarding by conventional methods is the best way. In the present studies, for LT-SOFC, three composite cathode materials (Pb_0.1Fe_0.4Co_0.5O_4-δ, Pb_0.2Fe_0.3Co_0.5O_4-δ and Pb_0.3Fe_0.2Co_0.5O_4-δ) were produced by extracting Pb from the waste lead acid batteries, cobalt nitrate [Co(NO₃)₃.6H₂O] and iron nitrate [Fe(NO₃)₃.9H₂O] using standard solid state reaction method. Thermal stability, morphological and structural characteristics were studied by TGA, SEM and XRD analyses. FTIR spectra were used to investigate the types of metal oxide bonding in the prepared ceramic composite cathode materials. Fuel cell testing and DC four probes were used to investigate electrochemical properties. The measurement of average crystalline size of the composites was found to be in the range of 12–37 nm.Scanning electron microscopy (SEM) images showed that composite materials are porous and suitable to diffuse the gases. The maximum conductivities of 1.6 Scm^?1, 2.05 Scm^?1 and 2.6 Scm^?1 have been obtained for Pb_0.1Fe_0.4Co_0.5O_4-δ, Pb_0.2Fe_0.3Co_0.5O_4-δ and Pb_0.3Fe_0.2Co_0.5O_4-δ, respectively. At 600 °C, the high OCV (0.95V) and the maximum power density (439 mW/cm²) have been achieved using hydrogen as the fuel. Lower value of activation energy (0.36ev) of Pb_0.3Fe_0.2Co_0.5O_4-δ confirms that it is the efficient material to convert electrochemically hydrogen fuel into valuable electricity.     

下辽河盆地西部斜坡区砂岩型铀矿成矿地质条件分析

为分析下辽河盆地西部斜坡区砂岩型铀矿成矿地质条件,本次研究通过收集整理下辽河盆地以往地质勘查资料,利用煤田钻孔资料的"二次开发",结合野外地质调查及能谱测量工作,对盆地的铀源条件、盆地构造及"补—径—排"体系、目的层条件等进行了分析,认为下辽河盆地西部斜坡区砂岩型铀矿成矿地质条件良好,其中明化镇组是成矿最有利层位;在控矿因素研究基础上,圈定了欢喜岭—盘山、大虎山—大民屯两个砂岩型铀矿成矿远景区,为进一步勘查提供思路。     

阿尔泰南缘泥盆纪火山－沉积盆地形成机制探讨

经过野外观测和室内分析测试，认为阿尔泰南缘三个等间距斜列的麦兹、克朗、冲乎尔火山沉积盆地中，广泛分布着泥盆纪火山沉积建造，它们控制着阿尔泰南缘多金属矿带的展布     

川南地区五峰组—龙马溪组页岩层序地层及其对储层的控制

随着四川盆地勘探程度的深入,页岩气藏已经成为勘探重点,有必要系统地开展页岩层序地层研究。在岩石地层、生物地层、年代地层研究的基础上,运用露头-钻井-地震、全球海平面变化曲线、地球化学、古生物等资料,在川南地区五峰组—龙马溪组页岩地层中识别出4个三级层序界面,划分了3个三级层序:SQ1相当于五峰组,沉积速率低(1.18~2.19 m/Ma);SQ2相当于龙马溪组下段及上段底部,沉积速率较低(约为15 m/Ma);SQ3相当于龙马溪组上段中上部,沉积速率较高(216.25~340 m/Ma)。建立了该区的层序地层格架。分析了层序对储层的控制作用,主要体现在黑色页岩层序SQ1—SQ2中相对海平面升降与页岩脆性指数呈负相关、与TOC及孔隙度呈正相关,渗透率高值多位于脆性段,渗透率低值多位于塑性段。灰色页岩层序SQ3以塑性段为主,孔、渗均低于SQ1、SQ2凝缩段,其相对海平面与有机质没有明显的相关性。相对海平面变化影响了优质页岩储层发育,SQ1、SQ2海侵期—海退早期为优质页岩储层发育期。综合本次研究成果,明确了层序地层对优质页岩储层的控制作用,对于在层序格架内预测优质页岩储层段具有指导意义。     

反凝析作用对苏里格气田上古生界气藏开发的影响

鄂尔多斯盆地苏里格气田上古生界气藏在开发中产生一定量的凝析油,含量约为10g/m~3,属于微含凝析油气藏,如果生产初期配产过大,那压力下降就会过快。在反凝析作用下,凝析油在近井地带析出形成多相流,堵塞微孔隙和吼道,导致气相渗透率降低,使得气井产量大幅下降,部分被封闭的天然气无法采出,层内凝析对储层的伤害有可能是永久性的。为此,通过对该气藏层内反凝析机理、层内凝析影响因素的分析及室内试验.再使用新建立的三维数学模型对单井进行预测,结果表明该气藏"三低"(低孔、低渗、低产)特征加剧了凝析液对储层的伤害。同时还分析了气井产能降低的根本原因.并对气井生产管理提出了建议:①在保护开采阶段,投产初期应合理配产,以低于无阻流量的1/5~1/8配产,尽可能延长露点线以上开采时间,使凝析油尽可能不在地层中析出;②在反凝析阶段,要在系统研究的基础上得出准确的相态图,要快速通过该阶段尽早进入蒸发阶段,使已经凝析出来的凝析油再次蒸发汽化,从而降低储层污染。该研究成果对苏里格气田上古生界气藏的科学开发以及进一步提高采收率具有重要意义。