五百梯长兴生物礁气藏储层连通性分析

五百梯长兴生物礁气藏储层岩性以白云岩为主,储层渗透性差非均质性很强。因此对该气藏连通性的研究是必要的。本文通过分析气藏的气体性质和折算地层压力在静态上来判断气藏是否连通,再通过井间干扰测试在动态上描述气藏连通性的好坏。连通性问题的研究能够直接指导五百梯长兴生物礁气藏生产,对于类似气藏也具有很好的借鉴和指导意义。     

酸碱两种方法消解-电感耦合等离子体发射光谱法(ICP-AES)分析空气滤膜样品中的19种元素

特氟龙空气滤膜试样用反王水浸泡预消解,电热板加热,反王水-高氯酸-氢氟酸四酸体系分解滤膜样品吸附的空气颗粒物。在无合适监控样品的情况下,采用国家一级标准物质GBW07401模拟滤膜吸附的空气颗粒物与空白滤膜一起消化分解、上机测定,优化ICP-AES光谱仪的最佳测试条件,分析样品中的Ba、Cr、Cu、Li、Mn、Ni、P、Pb、Sr、Ti、V、Zn、Al、Ca、Fe、K、Mg、Na共18种元素,测定值与标准物质的认定值相符,各元素分析结果的相对标准偏差RSD在1.42%～9.21%之间,方法回收率在89%～112%之间,元素检出限在0.002 0～0.35 μg/g 之间。滤膜中的Si元素测定采用微波马弗炉碱熔法,水提取酸化定容,同步采用国家一级标准物质GBW03105a模拟空气颗粒物样品加入空白滤膜,灰化碱熔,进行ICP AES测定。相对标准偏差RSD为7.68%,检出限为0.12 μg/g。采用酸溶法和碱熔法2种方法分解样品,实现了空气滤膜样品中19个多元素的快速测定。     

临泽杨台洼滩凹凸棒粘土及石膏矿床

杨台洼滩凹凸棒粘土及石膏矿床,分别发现于1993年、1956年。该矿矿层厚度大、延展面积广,除具有国内外凹凸棒粘土共同具有的物化性能之外,其独特性是含有大量微量营养元素,具有较大的经济意义。填补了我省该类矿床的空白。     

近500年来咸海湖泊沉积记录的环境演变

过去的五十年里,作为曾经世界第四大湖泊的咸海面积急剧萎缩,环境质量严重下降并对大部分中亚地区造成了灾难性的影响.咸海的水位下降过程虽然历时相对较短却变化显著,为了了解这一变化的详细过程,1997年从咸海北部湖盆采集了AS17孔浅钻岩芯.通过对该岩芯的矿物学、介形虫、孢粉等沉积环境指标综合分析,结果表明岩芯在矿物学特征及生物特征上的一系列显著变化,揭示了过去近500年中咸海的沉积环境经历了含盐量增加-下降-再增加三个明显的阶段,并为15世纪咸海的干旱提供了新的证据.     

Fatigue Behavior of Granite Subjected to Cyclic Loading Under Triaxial Compression Condition

A series of laboratory tests were performed to examine the fatigue behavior of granite subjected to cyclic loading under triaxial compression condition. In these tests, the influences of volumetric change and residual strain on the deformation modulus of granite under triaxial cyclic compression were investigated. It is shown that the fatigue behavior of granite varies with the tendency for volumetric change in triaxial cyclic compression tests. In the stress–strain space, there are three domains for fatigue behavior of rock subjected to cyclic loading, namely the volumetric compaction, volumetric dilation with strain-hardening behavior, and volumetric dilation with strain-softening behavior domains. In the different domains, the microscopic mechanisms for rock deformation are different. It was also found that the stress level corresponding to the transition from volumetric compaction to volumetric dilation could be considered as the threshold for fatigue failure. The potential of fatigue deformation was compared with that of plastic deformation. The comparison shows that rocks exhibit higher resistances to volumetric deformation under cyclic loading than under plastic loading. The influence of residual strain on the fatigue behavior of rock was also investigated. It was found that the axial residual strain could be a better option to describe the fatigue behavior of rock than the loading cycle number. A constitutive model for the fatigue behavior of rock subjected to cyclic loading is proposed according to the test results and discussion. In the model, the axial residual strain is considered as an internal state variable. The influences of confining pressure and peak deviatoric stress on the deformation modulus are considered in a term named the equivalent stress. Comparison of test results with model predictions shows that the proposed model is capable of describing the prepeak fatigue behavior of rock subjected to cyclic loading.     

佳木斯地块北部早古生代沉积建造的时代与物源:来自岩浆和碎屑锆石U-Pb年龄及Hf同位素的制约

本文对出露于佳木斯地块北部金银库组变沉积岩和侵入其中的火成岩脉体中的锆石进行了系统的LA-ICP-MS/SIMS U-Pb定年和Hf同位素研究,旨在限定金银库组的沉积时限,并揭示其物源及沉积环境。3个样品中锆石呈自形-半自形,显示典型的岩浆生长环带或条痕状吸收,暗示其岩浆成因。研究结果显示:采自金银库组绢云母片岩中的碎屑锆石72个分析点给出1 955~457 Ma的年龄区间,主要峰期年龄为814、757、568、491和463 Ma,其ε_Hf（t）值为-13.9~-0.1,Hf同位素一阶段模式年龄T_DM1和二阶段模式年龄T_DM2分别为1 827~1 307 Ma和2 411~1 715 Ma。采自侵入金银库组的花岗细晶岩和辉绿岩分别给出了263和267 Ma的结晶年龄,前者的ε_Hf（t）值为0.9~2.0,Hf同位素二阶段模式年龄T_DM2为1 110~1 047 Ma;后者的ε_Hf（t）值为-7.7~6.4,Hf同位素一阶段模式年龄T_DM1为1 206~662 Ma。结合佳木斯地块及邻区约430 Ma火成岩的存在和金银库组中该期碎屑锆石的缺乏以及碎屑锆石年龄众数及其Hf同位素组成,我们认为金银库组的形成时代应为晚奥陶世至早志留世（463~430 Ma）,形成于被动大陆边缘背景,沉积物源主要来自佳木斯地块及其邻区的古元古代和早古生代早期火成岩。     

基于子流域特征的泥石流易发性评价

文章以云南省迪庆藏族自治州金沙江河谷金江镇—林当可为例,研究了基于子流域单元的泥石流易发性评价模型。首先,将研究区划分为1 570个子流域单元,其中70%(1 090个)用于模型建立,30%(480个)作为模型测试样本。然后,采用9种子流域单元特征因子（melton比率、流域平均径流侵蚀力指数、平均地形湿度指数、流域延伸率、流域平均高程、流域水系密度、流域平均植被覆盖度、流域平均坡度、流域高差率）的归一化值作为自变量,泥石流是否发育作为因变量,运用逻辑回归建立泥石流易发性评价模型,将易发性划分为5个等级。最后,通过独立的测试样本验证,易发性评价模型预测性能(AUC=0.821)良好;且随着易发性等级提高,泥石流绝对和相对发育比例逐级增加,模型满足合理性要求,适用于研究区的泥石流易发性评价。     

应用Excel VBA编制煤田钻孔综合成果整理程序

煤田钻孔综合成果的整理、统计计算,是柱状图绘制、煤层对比和储量计算的重要基础工作。传统的整理工作虽然已经借助于Excel,但是手动处理耗时耗力。为了提高工作效率和准确率,应用VBA语言开发了一个钻孔综合成果整理程序,并把它应用于贵州省赫章县结构勘查区煤炭勘探项目中。应用证明,该程序比传统的手动处理省时省力,准确度高。     

WJH多功能电位分析仪测试系统软件设计

在研制WJH多功能电位分析仪硬件基础上所设计的测试系统软件,它结合电位分析的原理和数理方法,采用汇编语言和BASIC语言设计出两次标准加入法、计算法、增量法、减量法、电位滴定法、pH测定、绝对mV值测定等10种测试方法的系统软件,实现了测量、计算、结果处理、CRT显示、打印自动化。     

Identification of Eolian Sandstone in Cretaceous Uraniferous Sandstone in Ordos Basin,ChinaEI北大核心CSCD

Uraniferous rocks in the lower part of Cretaceous Luohe Formation of Well XX located at the southwestern Ordos Basin have been investigated through core logging, microscopic observation, scanning electron microscope and granularity analyses. The desert (lower part) and ephemeralalluvial (upper part) sedimentary facies, composed of dune, interdune, sandsheet, wadi, and channel, bank subfacies are identified. The lower part of the Luohe Formation consists of red, yellow, and grayish green coarse- to fine-grained sandstone. The sandstone lacks cement and matrix, and quartz grains as the main mineral component are commonly clean and bright, with a small amount of debris (sedimentary debris) and feldspar (microcline and striped feldspar), indicating a high composition maturity. These particles are mostly medium-fine, sub-angular to sub-rounded, and the grain size distribution is mainly concentrated between 2.2ϕ and 3ϕ. The grain size curve shows that the sandstone is mainly composed of jumping transport components, with a small amount of suspended transport components, which means that the sandstone is well sorted and structurally high mature. Large scale and high angle cross bedding, parallel bedding, and wavy bedding are common, and tongue shaped grain flow with upward or downward pinching, wind ripple strata with reverse grain sequence, pin stripe lamination with dark color can be identified in the layer. Under scanning electron microscope, a series of dished and crescent impact craters, pockmarks, chemical dissolution and precipitation, desert paint, and other phenomena are identified on the surface of sandstone particles. Comparing with the characteristics of typical fluvial sandstone and eolian sandstone, the uraniferous sandstone in the lower part of the Luohe Formation in the southwestern Ordos Basin is of typical eolian sandstone. The eolian uraniferous sandstone is a new type of uranium-bearing sandstone reservoirs in the world, and this discovery expands the exploration space and potential for uranium deposits in North China, and provides new direction for further exploration of sandstone type uranium deposits. Further research is still underway. © 2020, Science Press. All right reserved.