东濮凹陷西斜坡复杂断裂带构造-沉积演化研究

东濮凹陷西斜坡W块属于极复杂断块,目前构造形成与演化认识不清楚,从而制约着微构造研究。然而,从其内部沉积发育演化规律上看,发现复杂构造的形态具有一定的规律。W块的两个井区(A井区和B井区),在沙三段沉积具有明显的继承性。W块地层表现为粗砂岩—中砂岩的特征,随着构造应力的转换,W块地层沉积逐步过渡到细砂岩—粉砂岩—泥质粉砂岩的特征,并且在不同亚段沉积时期古水流活动区域也在变化。沙三中4—中5沉积时期,B井区发育稳定的砂泥互层旋回,而A井区砂体发育较差;至沙三中2沉积时期,A井区砂体发育开始变好,B井区砂体发育开始变差。构造活动控制同期沉积作用的进行,古河道的迁移演化反映该沉积时期构造应力的活动。结合区域构造背景分析判断构造应力活动的时间,从而确定断层形成期次,总结断层的发育规律,有利于剩余油的挖潜。     

黄骅坳陷孔南地区中生界地层厘定与沉积演化特征

长期以来黄骅坳陷孔南地区油气勘探主要集中在新生界,中生界由于埋藏深、地质构造复杂,对地层认识较欠缺。本次研究在借鉴冀中坳陷中生界地层层序划分,通过孔南地区古生物化石鉴定、沉积韵律旋回性对比、精细层位标定识别不整合面、井震结合地层对比等技术手段,首次开展中生界顶底界限研究,建立起中生界层组精细划分与对比标准,并开展沉积演化特征分析。研究结果表明:孔南地区中生界地层化石组合具有典型侏罗系化石组合特征,古生物化石资料、测井资料、地震资料证实中生界顶为大套安山岩之下一组砂泥岩韵律层的底,其底界为石千峰群之上的含砾砂岩段底界。孔南地区中生界地层自下而上依次划分为葛渔城组、杨村组及苏桥组,葛渔城组与苏桥组以辫状河沉积为主,杨村组以曲流河沉积为主,砂体展布主要受北部、东部及西南部3个方向的物源控制。     

我国能源战略研究中的区域划分方法探讨

针对我国经济发展过程中,城乡之间以及地区之间的经济状况存在巨大差异的现象,本文首次提出了挖孔式分区法,该方法及其特点进行了详细的阐述,并给出了该方法在广东省内进行区域划分的一个应用实例。该方法可以将经济发展状况存在巨大差异的地区划分在不同的子区域中,每个子区域的宏观经济特征不尽相同。消除了按照同级、边界相邻的行政区划简单地将大区域划分成小区域,各子区域内部的巨大地区差异和城乡差别仍然存在的现象,而子区域之间却具有相同或相似的经济统计特征。该新方法有利于子区域之间各种特征的突出表征和量化比较。利用这种方法在我国的某个范围所建立的区域划分结果,有利于更加合理地考察城乡之间的差别和地区之间的差别。     

基于RS和GIS的藏东南地区泥石流物源信息提取及典型泥石流分析

为研究泥石流灾害对藏东南地区的影响和危害,利用RS和GIS技术对研究区泥石流物源进行遥感信息提取及特征分布分析,将所有物源分为八类,得出研究区泥石流物源分布不均匀,物源分布主要受地震、地质构造、气候条件、地层岩性、海拔高程、地形坡度等因素的综合影响,进而将该地区泥石流分为冰湖溃决型、冰雪消融型、冰雪消融和降雨混合型、降雨型、冰崩雪崩型泥石流五类,从中各选取一条典型泥石流沟,并从物源角度进行了阐述,得出除沟道堆积物外,分布在泥石流沟中上游的其他物源补给不同类型泥石流呈现一定差异。     

黔东南麻江-凯里地区志留系油砂矿储层特征

贵州东南部麻江-凯里地区油砂资源丰富,构造上处于上扬子地台黔南坳陷东部,东邻雪峰山推覆体,北西与黔中隆起及武陵坳陷相接。通过野外露头和浅井岩心观察,运用铸体薄片鉴定、物性分析及含油率测试等手段,对该地区志留系翁项群油砂储层特征及含油性特征进行了研究。结果表明:研究区油砂主要发育在翁项群二段和三段中,含油砂岩成分成熟度和结构成熟度中等一好,岩性均以中—细粒(含)钙质、硅质岩屑石英砂岩和石英砂岩为主;凯里地区含油砂岩胶结物含量在8%~23%之间,以亮晶方解石为主,局部连晶,硅质胶结物含量在1%~10%之间,以石英次生加大边产出,而麻江地区含油砂岩胶结物含量仅为1%~7%,以硅质胶结物为主;研究区砂岩发育有原生粒间孔、粒间溶孔、粒内溶孔、铸模孔及裂缝等孔隙类型,以原生粒间孔为主,孔隙度介于0.3%~7.0%之间,渗透率介于0.006×10~(-3)~6.21×10~3μm~2之间,为低孔低渗储层,恢复含油率平均值为3.73%。结合以上测试手段和实验分析结果,判断凯里地区油砂含油性较麻江地区稍好。     

东门地矿区童子岩组第三段主采煤层聚煤模式及其演化探讨

从沉积物成份、结构、构造、古生物化石、砂岩体及煤层稳定性、地球化学、煤质、测井曲线等九大特征进行分析,根据沉积特征,探讨聚煤模式,总结沉积环境演化过程。     

煤层在层序地层学划分对比中的意义——以准噶尔盆地白家海地区侏罗系为例

煤层是层序格架内的标志性沉积物,对其发育规律的认识有助于层序地层学研究工作的开展。以准噶尔盆地东部白家海地区侏罗系为例,通过对古地貌、砂岩百分比及重矿物百分含量的分析,确定古物源的演化规律,再结合古气候、岩性、录井及基准面变化等资料,研究该地区煤层发育的控制因素。对该地区几个聚煤时期碎屑物质的供应程度、古植物、古气候、及湖平面(基准面)变化、古地貌格局,以及可容空间变化率与古气候变化的关系等进行综合研究,认为“有效”可容空间演化历史控制层序地层时空展布特征,是影响煤层在层序格架中展布规律的关键因素。该地区侏罗系煤层受沉积古地貌、碎屑供应程度及古气候等多种因素共同控制,并主要发育于基准面较长期稳定上升的阶段,与层序的时空演化存在着有机联系。     

王官屯油田官142地区中生界地层特征

王官屯油田地处河北省沧县王官屯乡境内,区域构造位置为黄骅坳陷南区孔店构造带的西南端,处于孔东断裂带两侧。根据钻录井特征、地球物理响应特征,结合区域地层对比,将王官屯油田官142地区中生界地层划分为中下三叠统、中下侏罗统、上侏罗统-下白垩统三套旋回。通过对该区地层特征的分析,认为中下三叠统以棕红、紫红色粉细砂岩和泥岩互层为主;中下侏罗统下部主要为暗色泥岩夹砂岩,上部为一套巨厚砂砾岩,并作为中生界油藏主要储集层;上侏罗统-下白垩统发育紫红色砂岩及安山岩。通过分析各时期的构造运动特征,认为印支运动以整体抬升为主,发育了三叠系地层;燕山早期以走滑和挤压为主,盆地规模较小,发育中下侏罗统的河湖相沉积;燕山中期火山活动强烈,发育火山物质为主的晚侏罗世-早白垩世地层;燕山晚期该区整体抬升遭受剥蚀,缺失上白垩统地层。而喜山时期的升降运动对中生界油气成藏具有重要意义。     

致密砂岩气藏特低渗原因剖析

论述了致密砂岩气藏特低渗形成的原因:即先天的沉积因素和后天的成岩作用等。得出结论:近源和远源沉积、矿物成熟度和矿物的泥化硅化、压实胶结、有无烃类饱和以及是否接触泥岩层都是影响致密砂岩气藏渗透率的因素。     

白云凹陷陆架坡折带识别方法

珠江口盆地深水区的油气勘探已获得战略性突破,为提高勘探成功率及降低勘探开发成本,需要运用层序地层学,对深水沉积体系进行研究。深水沉积体系研究发现,陆架坡折带为重力流发生的主要区域,其连接着物源与深水扇,控制高位域砂体的分布与深水扇的发育。陆架坡折带的识别,在低位域深水扇的分析中具有承上启下的作用。本文阐述了陆架坡折带在深水沉积体系研究中的意义,并以白云凹陷为靶区,总结了进行陆架坡折带识别的多种方法。当海退规模较大、陆源充足时,三角洲前积最后一个顶超点就是陆架坡折带;当海退规模较小,或陆源供给不足时,需要结合地层侵蚀、海侵期地层初始上超点、三角洲前积、层序界面之上深切谷出现位置、地震属性图变化特征、沉积水道指向突变、钻井岩性-电性组合及横向对比变化等多种因素,进行综合判断。     

Adsorption of a nonionic surfactant onto a silica surface

Chemical flooding is technically feasible to increase oil recovery from depleted sandstone reservoirs with low pressure. Polymer-surfactant flooding is a potential process in the chemical flooding methods for enhanced oil recovery (EOR) in sandstone porous media. However, chemical additive cost and surfactant loss due to adsorption on the reservoir rock are the main concerns in this type of EOR processes. This paper presents adsorption equilibrium of a natural surfactant, Zyziphus spina-christi, onto a real sandstone reservoir. Batch adsorption experiments were carried out to figure out the impacts of adsorbent dose on adsorption performance. The equilibrium adsorption data were analyzed with two common adsorption models and it was found that the Freundlich model is a pretty good fit for adsorption equilibrium of Z. spina-christi based on the value of determination coefficient (R²). Results from this study are instructive for appropriate selection of surfactants in design of EOR processes and reservoir stimulation plans for sandstone reservoirs.     

东濮凹陷杜桥白区深层储层主控因素研究

为了进一步了解东濮凹陷杜桥白地区深部(3 500 m)油气储集层物性主控因素,在已有资料的基础上分析了东濮凹陷深部储层特征物性并对其作出了评价。综合分析结果表明,东濮凹陷内深部油气藏储层主要为古近系沙河街组三段(Es3)砂岩,影响储集层物性主控因素主要为与沉积环境和岩相有关沉积物的初始物质成分特征、受成岩过程和埋藏深度影响压实作用及受构造作用。     

Analysis of output power smoothing method of the solar chimney power generating system

Severe fluctuation of the output power is a common problem in the generating systems of various renewable energies. The concept of output power fluctuation factor of renewable energy power generating systems was put forward in this paper. Aiming to decrease the fluctuation factor of output power in solar chimney power generating systems (SC), a novel hybrid energy storage system made of water, and sandstone was employed to replace the traditional sandstone energy storage system. The mathematical models of fluid flow, heat transfer and power generating features of SC were established and the influences of material, depth, areas and location of the energy storage layer upon output power were analyzed. The simulation results indicated that adopting the hybrid energy storage of water and sandstone can effectively decrease the fluctuation factor of SC output power and hence smooth the SC output power. In addition, according to the largest daily power generating capability or the smallest peak fluctuation factor, the corresponding optimum depth of the water energy storage layer would be 5 cm or 20 cm, respectively. Copyright © 2012 John Wiley & Sons, Ltd.     

基于轴-径环状分层CT扫描的岩石冻融损伤分析

为研究岩石在冻融循环作用下的破坏损伤机理,结合CT扫描分析法,提出了一种基于轴-径环状分层精确CT扫描的岩石冻融损伤分析方法,将该方法运用于三峡库区砂岩的冻融循环损伤分析,并对各阶段损伤砂岩进行三轴加载试验。结果表明,同一冻融循环次数下,砂岩体积CT值由外向内不断增大,且越靠近外圈层体积CT值减幅越大;随着循环次数增加,损伤变化表现为由外向内的渐进式损伤破坏,在初始损伤阶段,损伤集中于砂岩外层,体积CT值、三轴峰值应力及破坏应变变幅较小;深层损伤阶段,砂岩外部外圈剥落,冻融损伤侵入内部,此时体积CT值、三轴峰值抗压强度及破坏应变变幅明显增大。该方法对岩石冻融损伤分析及冻融灾害防治具有重要的现实意义。     

周期性荷载作用下岩石力学特性数值模拟研究

为研究周期性荷载作用下岩石的力学特性,开展了基于离散单元法(DEM)的岩石疲劳数值模拟试验,通过模拟单轴压缩试验研究了数值模型中微观参数对试样宏观参数的影响,再通过数值疲劳试验研究了砂岩的疲劳变形特性。结果表明,砂岩的疲劳应力—应变曲线受控于单轴应力—应变过程曲线,疲劳破坏时的轴向应变即为周期性荷载最大应力在单轴应力—应变曲线中所对应的峰后部分应变。通过分析砂岩的疲劳渐进破坏过程发现,最大应力和平均应力是影响砂岩疲劳寿命的两个重要因素。研究成果对于了解岩体疲劳破坏机理、合理评价工程稳定性有重要意义。     

R-Matrix Theory for Nanoscale Phonon Thermal Transport across Devices and Interfaces

We have adapted R-matrix theory to calculate phonon scattering across systems of molecular to mesoscopic scale. The key novelty of this work is that the only required information about the scattering region is its normal modes, which are evaluated only once for a system. Thus, R-matrix theory is a computationally efficient and simple approach to calculate phonon scattering in larger systems. To validate and to demonstrate the applicability of the theory, we apply it to two systems: a one-dimensional chain of atoms and a graphene nanoribbon. In both cases, we discuss the effect of mass impurities on thermal transport.     

南海北部陆坡天然气水合物成藏特征研究进展分析

南海北部陆坡区域构造地质控制着气源、流体疏导体系、富集空间及储层物性特征,因此,东沙海域、神狐海域、西沙海槽和琼东南盆地的水合物成藏条件及控制因素具有明显差异性。东沙海域深部气体可沿断层、裂缝、不整合面、砂岩疏导层和气烟囱等通道向上运移,并形成天然气水合物,具有渗漏型水合物产出特征;神狐海域水合物成藏与规模巨大的泥底辟活动相关,并与布莱克海台天然气水合物产出特征具有相似性;琼东南盆地中央坳陷带内为天然气水合物发育的重点区,底辟、泥火山或麻坑构造与天然气水合物发育密切相关。     

The effect of clay on initial and residual saturation of hydrogen in clay-rich sandstone formation: Implications for underground hydrogen storage

Understanding wettability in rock-brine-hydrogen systems is essential for dependable predictions of capillary/residual trapping in clay-rich sandstone formations. Despite being the most used technique, wettability assessment based on contact angle measurements is confronted with inherent uncertainties that limit its reliability. In contrast, core flooding techniques provide a more direct and realistic picture of wettability and its time evolution. Nuclear Magnetic Resonance (NMR) allows us to evaluate the initial and residual hydrogen saturations and distribution along the core specimen. It is a fast, reliable, and effective way of inferring the impact of wettability on hydrogen migration, and residual trapping in prospective geo-storage rock formations. Recent publications have reported the evaluation of wettability in a brine-hydrogen-rock system where the rock is a clean sandstone (no clays). Here we evaluate the impact of the presence of clays in a sandstone, which has not been reported yet. NMR monitoring was employed to characterize the initial and residual hydrogen saturations in the Bandera Grey (BG) sandstone. To investigate the impact of clay minerals on hydrogen saturation, same rock sample was characterized in its natural state, and after heating it to 700 °C for 12 h in an air environment to burn off clay minerals, During the NMR core flooding experiments, ten pore volumes (PVs) were injected/withdrawn during the drainage/imbibition cycles at a fluid injection rate of 2 mL/min under room temperature and 1000 psi confining pressure. Due to the hydrophilicity of quartz and clay, the tested BG sandstone (clay-rich sandstone) shows a significant residual/trapped saturation (～3.5% can be reproduce); therefore, clay-rich sandstone may not be ideal for hydrogen storage unless cushion gas is used.The results show that initial and residual hydrogen saturations were slightly changed after firing (from 16% to 18% for initial and from 14% to 13% for residual). This also suggests that the wettability of the BG sandstone-brine-hydrogen system is slightly impacted by clay content and type. We also observed that clay firing at 700 °C has little effect on the porosity and gas permeability of the BG sandstone. Moreover, X-ray powder diffraction (XRD) results showed that quartz content increases from 68.1% to 76.2%, Kaolinite transformed into illite and clinochlore disappeared. The disappearance of chlorite after firing suggests that it is transformed into another clay type.     

Permeability Reduction Due to Formation Damage by Drilling Fluids

Abstract

In this study, investigation of permeability reduction due to formation damage by invaded drilling fluids of sandstone-based, lime-containing core plugs from the southeastern region of Turkey were studied. The tests were performed by using dynamic filtration set-up that was constructed at the laboratory. In the experiments, nine core plugs of 7 cm length and 3.81 cm (1.5 in) diameter were used. Three different drilling fluid types using two different polymers were prepared and tests were made at three different filtration pressures. The direct effect of filtration pressure on fines migration was studied. The filtration properties and the thicknesses of the filter cakes were measured. It was observed that permeability of the sandstone samples reduced due to circulation of the drilling fluid and the filter cake thickness increased with increasing differential well bore pressure.     

金沙江向家坝水电站坝基砂岩蠕变特性研究

选取了金沙江向家坝水电站坝基的典型砂岩试样,采用三轴压缩试验对砂岩蠕变特性进行研究,分析了流变失稳破坏时的特征及砂岩的轴向、侧向和体积应变的全过程蠕变曲线异同点,对砂岩的长期强度进行预测分析。试验结果表明,砂岩存在一个起始蠕变应力阈值,每级荷载下的蠕变曲线之前都存在一个瞬时应变且随着围压的增大和偏应力的增大幅度越来越小,轴向瞬时应变与偏应力具有很好的线性关系;侧向和体积变形则存在明显的蠕变三阶段,加速阶段要比轴向快且两者的蠕变曲线形状相似,在同一围压和同一级偏应力下侧向蠕变量比轴向及体积的大,其蠕变发展最快;砂岩的长期强度可用等时偏应力应变曲线簇来进行确定,采用体积偏应力应变曲线簇更适宜,在已有的流变模型中伯格斯模型能较好的反映砂岩蠕变特性。