石油二次运移物理模拟及运移特征分析

石油二次运移是一个复杂的地质过程,本文通过利用饱和地层水的低孔低渗储层砂岩来进行石油二次运移模拟实验,初步研究了此过程的变化特征。研究表明 :在静水条件下,石油水平运移带的平均含油饱和度达 15 %~2 5 %。运移过程中饱和烃、芳烃及非烃与含油饱和度呈正相关性。在运载层物性相差较小的情况下,运移驱动力是运移效率的主导因素。在孔渗性好的运载层,含油饱和度容易达到稳定。     

人工神经网络在致密砂岩气层识别中的应用

致密砂岩气层识别是一个难题。如何在已有的地质、钻井、测井、地震等资料的基础上，利用现代人工智能方法进行气层识别，值得我们去探计。作者在本文中利用一个改进的BP网络模型，充分利用现有的地质、测井等资料，以单井为单元进行垂向气层识别，然后又以地震资料为约束进行气层横向预测，结果非常令人满意。     

Slake durability and mineralogical properties of some pyroclastic and sedimentary rocks

Slake durability of rocks is an important property of rock-mass and rock-materials in geotechnical practice. The slake durability of rocks is closely related to their mineralogical composition. In this paper, mineralogical examinations and slake durability tests for argillaceous clastic rocks, especially pyroclastic rocks, sandstones and mudstones of Neogene Tertiary age from Japan, were performed in order to assess the slake durability and rock alteration process of these rocks as well as to understand the relationship between mineralogy and durability.The mineral composition and textural features of the rocks were studied by means of optical microscopy (OM), X-ray diffractometry (XRD), electron microprobe analysis (EPMA), and scanning electron microscopy (SEM). In addition, the slake durability test was carried out by using the standard testing method of ISRM [Int. J. Rock Mech. Min. Sci. 16 (1979) 148] in distilled water and in the aqueous solutions with dissolved electrolytes of NaCl and CaCl₂.The pyroclastic rocks and tuffaceous sandstone, rich in di-octahedral and tri-octahedral Fe smectite, respectively, show distinctively different slaking behaviors. The pyroclastic rocks show relatively high slaking (Id₂=55.5% and Id₁₀=10.5%) than the tuffaceous sandstone (Id₂=94.1% and Id₁₀=87.8%, refer to text for Id₂ and Id₁₀). This difference in the slake durability observed in these rocks is due to the microscopic occurrences of smectite present in the interspaces between the particles (pyroclastic rocks) and zeolite cementing the interspaces (tuffaceous sandstone) as alteration minerals. In addition, the durability results of tuffaceous sandstone show that the slake durability decreases as the degree of weathering increases (weathered material Id₂=88.7% and Id₁₀=65.3%). Furthermore, two mudstones of Miocene and Pliocene ages, having different clay mineral compositions (smectite vs. illite+chlorite), show the lowest and the highest slake durability among the tested clastic rocks. Hard mudstone shows the highest (Id₂=98.1% and Id₁₀=95.5%) while the soft mudstone shows the lowest (Id₂=33.9% and Id₆=0.4%.) slake durability. Thus, the slake durability of pyroclastic and sedimentary rocks is greatly affected by their mineral composition and texture, and is closely related to their alteration history. Slake durability is also affected by the kind of dissolved electrolyte and its concentration in the aqueous solution, providing some useful information for geotechnical practice.     

东河储层敏感性参数与测井的响应关系

在岩心分析的基础上。分析和提取塔中“东河砂岩”储层的11个主要敏感性参数，同时利用常规测井方法可获得的岩石骨架。泥质含量。粘土矿物和物性参数等敏感性参数。然后在油田储层敏感性流动实验资料的基础上。运用逐步回归方法建立储层敏感性与测井资料的解释模型。对实际井进行处理分析。结果表明，由测井解释得到的储层敏感性结合与研究区的敏感性流动实验基本一致。     

川西双江口地区花岗岩的岩石学、地球化学特征及其成因研究

双江口地区出露的花岗岩主要为二云二长花岗岩和似斑状黑云花岗岩,二者呈侵入接触关系,在岩体特征、岩石颜色、结构、矿物组成及后期改造等方面存在较为明显的差异。岩相学特征表明二云二长花岗岩形成晚于似斑状花岗岩,岩石地球化学特征表明二者成因为部分熔融,物源为壳源,形成环境为同碰撞-造山带环境,形成时间为印支晚期。     

南海中部海域地震速度分析

从南海中部海域多次地球物理调查获得的速度资料中,挑选3 000多个速度谱点,经过解释直接或间接地获得该区200多条剖面上各点的叠加速度、均方根速度、层速度等多种速度资料,并计算出该区的时深转换和砂岩百分含量。综合各剖面上的速度变化和Ps值(砂岩百分含量)特征,编制了晚始新世以来地层速度和Ps值平面图,分析各时代层速度和Ps值的纵向和横向变化规律。得出南海中部海域物源早期来自西北方向,中期西南方向,最后远离物源的变化过程,海水进侵方向为东南方向。进而说明该区经历了初期冲积平原、中期滨海—浅海和晚期浅海—半深海的充填演化过程。为研究该区的地层沉积特征和沉积模式提供依据。     

准噶尔盆地北三台凸起新近系含铀砂层分布预测

通过对准噶尔盆地北三台凸起油气钻井的录、测井等资料分析发现,在新近系沙湾组底部发育一套异常高自然伽马砂砾岩,其中B311 井GR值最高达1 732.58 API,预示该区具有良好铀资源勘探前景.为准确预测该区含铀砂岩分布,通过精细的合成记录标定,对该含铀砂层提取地震属性.通过多属性融合与分析,预测含铀砂层平面分布,进而...     

伊犁盆地南缘可地浸砂岩型铀矿床远景地段影像特征及识别

本文阐述了科学试验卫星像片的二次开发研究,计算机三维立体模拟显示及多参数特征提取的原理、方法和步骤;综合研究了伊犁盆地南缘可地浸砂岩型铀矿不同级别的远景地段在不同类型影像上的特征,分析了远景地段影像特征的内涵及地质意义,并据此对远景地段影像特征进行了识别。在此基础上,采用层层剥笋、步步深入、逐次缩小范围的方法,对伊犁盆地从区域成矿远景、有利地段（靶区）的优选到矿区范围有利勘探地段进行了逐步分级预测,取得了良好的验证效果。     

鄂尔多斯盆地盐池-姬塬地区三叠系长2砂岩成岩演化特征与优质储层分布

盐池-姬塬地区延长组长2砂岩由三角洲前缘水下分流河道和河口坝砂体组成,以岩屑长石砂岩和长石砂岩为主,其中石英、长石和岩屑平均含量分别为32.6%,38.9%和8.0%,岩屑以变质岩屑和火成岩屑为主,占岩屑总量的87.5%。砂岩目前处于早成岩阶段B期的晚期,RO为0.8%,温度在70℃～90℃,成岩组构特征受酸性成岩环境控制,因此长石类易溶颗粒普遍发生溶蚀作用,石英次生加大发育。孔隙类型组成中原生粒间孔隙所占比例多在30%～45%之间,粒间和粒内溶孔占40%～55%。在对砂岩各种组分含量统计的基础上,定量计算表明机械压实作用是造成研究区原生孔隙消亡的最主要原因,其次为胶结作用,而由溶蚀作用增加的孔隙占初始孔隙度比例较小(<10%)。结合沉积相分析成果,在研究区可划分出5种沉积-成岩相带,其中有利的高孔高渗储层(孔隙度>14%,渗透率>5×10-3μm2)分布区主要由三角洲平原分流河道-次生溶孔相前锋带、三角洲平原分流河道-绿泥石粘土膜胶结次生溶孔相前锋带和台型三角洲前缘-绿泥石粘土膜胶结原生孔相主体以及坡型三角洲前缘-次生溶孔相主体组成。     

Evaluating spatial variation of suspended sediment rating curves in the middle Yellow River basin,China

Abstract The suspended sediment load in the middle Yellow River basin (YRB) cannot be well predicted by capacity‐based transport formulas because a large fraction of suspended sediment load is composed of wash load. This study evaluated the spatial variations of sediment rating curves (SRCs) in the middle YRB. Both power and linear SRCs were used to fit daily flow and suspended sediment concentration (SSC) historical data at 49 gauging stations throughout the middle YRB. The spatial variation in regression coefficients was investigated, and the relationship between regression coefficients and the physical characteristics of watersheds was discussed. The results indicate that SRC regression coefficients vary with drainage area and basin slope, but their responses to these parameters are remarkably different in watersheds with different underlying surfaces, which indicates the significance of sediment availability, erodibility, and grain size distribution. For power SRCs representing sediment transport in unsaturated flows, the regression coefficients are more closely correlated with the drainage area in loess regions and with the basin slope in rock mountain regions. For linear SRCs representing sediment transport in saturated flows, saturated SSCs vary with coarse (particle size > 0.05 mm) and fine (particle size < 0.01 mm) fractions in suspended sediment. The maximum saturated SSC among the different gauging stations is associated with the optimal grain size composition of suspended sediment, which has been proposed for loess regions in previous studies. This study provides theoretical support for estimating the regression parameters for sediment transport modelling, especially in ungauged basins.