Medium-term effects of two landsliding episodes on channel storage of sediment

Two landsliding episodes between late 1973 and early 1975 delivered about 60000 m³ of sediment to six small deeply incised streams draining a 2·7 km² area. About 4700 m³ of logs in the landslide debris formed major log jams in five streams, which impounded large volumes of landslide-derived sediment. Five years after the landsliding, 42 per cent (25000 m³) of sediment was still in storage behind 35 log jams ranging from 1·4–8·2 m high. The landsliding episodes have produced multi-stepped stream profiles, aggradation of channel reaches up to 150 m long to mean depths between 1·2 and 4·1 m, reductions in gradient, fining of bed material size, and related changes in bedforms and channel width:depth ratios that seem likely to persist for at least several decades. Sediment presently stored behind log jams is equivalent to between 50 and 220 years normal supply of sediment from hillslopes to stream channels. Long-delayed, large magnitude impacts on higher-order channels may occur if sudden failure of log jams is induced by a large storm at some future date.     

密度测井和中子测井的相关性及其在识别天然气层中的应用

伽马射线与地层介质的康普顿（Ｃｏｍｐｔｏｎ）效应是密度测井的理论基础，介质对伽马射线的康普顿吸收系数取决于介质的原子核性质及其体积密度．（超热或热）中子测井主要反映地层介质的减速性质，而后者主要取决于介质的含氢量．介质含氢量是由介质的组分及其体积密度决定的．本文从上述两种测井方法的测量原理出发，从理论上证明了这两种测井方法并非两种互相独立的测量手段．对于含油气盆地常见沉积岩石及矿物，两种测井测量结果具有相关性．这一结论为密度、中子测井方法组合地质应用提供了理论依据，利用密度－中子测井的相关性可有效地识别轻质油气层特别是天然气层．实例表明，无论水层还是油气层，两种测井曲线均具有良好的相关性．利用这种相关性明显改善了识别天然气层和划分油－气界面的精度．     

自然伽马能谱测井薄层响应

自然伽马能谱测井的探测范围是一个直径约等于100cm的球体，粗略地说，厚度小于100cm的地层属于薄层．本文用实验研究和理论计算相结合的方法，对高放射性和低放射性两类薄地层的测井响应分别做了分析．所得结果可用于从低放射性厚储层中正确扣除高放射性泥岩薄层的影响，并在大段泥岩或交互层中划出薄储层．     

利用积分方程法计算双侧向测井仪的井眼校正曲线

对电测井积分方程中的各积分项进行了理论推导，利用任意闭合曲面对曲面外一点所张立体角为零的特点将电势积分项由对柱体侧面的积分转化为对柱体底面的积分，从而使在纵向采用线性插值条件下给出了电势积分项的解析解．对电流积分项进行了化简，使之由曲面积分化为一维数值积分．利用所得结果计算了双侧向测井仪的井眼校正曲线．     

新疆天文台天文观测数据传输日志系统设计与实现

新疆天文台望远镜产生的观测数据通过数据专线传输到新疆天文台本部数据中心进行长期存储。采用rsync进行数据传输,传输过程中没有详细的日志记录信息,无法对传输情况进行统计分析。通过调研新疆天文台数据传输的需求,设计并开发了新疆天文台观测数据传输日志系统。系统以新疆天文台南山站、奇台站的数据存储服务器和新疆天文台本部长期存储为基础,设计了日志系统的整体架构,实现了数据传输过程的日志记录。系统基于shell多线程技术及Qt框架,开发了后台服务程序及日志系统软件界面,实现了日志分析、统计备份与数据传输的可视化页面。     

Jusa and Barsuchi Log Volcanogenic Massive Sulfide Deposits from the Southern Urals of Russia: Tectonic Setting, Structure and Mode of Formation

The Jusa and Barsuchi Log volcanogenic massive sulfide (VMS) deposits formed along a paleo island arc in the east Magnitogrosk zone of the Southern Urals between ca 398 and 390 Ma. By analogy with the VMS deposits of the west Magnitogrosk zone, they are considered to be Baimak type deposits, which are Zn‐Cu‐Ba deposits containing Au, Ag and minor Pb. Detailed mapping and textural analysis of the two deposits shows that they formed as submarine hydrothermal mounds which were subsequently destroyed on the sea floor under the influence of ocean bottom currents and slumping. Both deposits display a ratio of the length to the maximum width of the deposit >15 and are characterized by ribbon‐like layers composed mainly of bedded ore and consisting principally of altered fine clastic ore facies. The Jusa deposit appears to have formed in two stages: deposition of colloform pyrite followed by deposition of copper–zinc–lead sulfides characterized by the close association of pyrite, chalcopyrite, sphalerite, galena, tennantite, arsenopyrite, marcasite, pyrrhotite, bornite, native gold and electrum and high concentrations of gold and silver. The low metamorphic grade of the east Magnitogorsk zone accounts for the exceptional degree of preservation of these deposits.     

对数泛克立格法在化探中的应用

在霍各乞多金属矿区找矿预测中,利用对数泛克立格法处理1/1万岩石地球化学测量数据资料,将其成果用于成矿条件分析,进行找矿预测.较滑动平均法、趋势面分析法具有估值精度高、系统误差小,且能进行结构分析和给出具体的估值精度等优点,该方法值得推广应用.     

两种浅海水深快速反演方法对比研究

针对对数比例变换法和多波段模型法两种操作简便的水深反演方法的优劣进行对比,旨在探讨二者对于大量浅海水深快速反演流程化工作的适用性。基于水深参考数据,随机选取138个样本点分别构建反演模型,并分层随机抽取100个验证点进行精度评价。从模型决定系数R2、反演精度,以及方法鲁棒性和适用性3个方面进行对比分析。结果表明,多波段模型法的决定系数R2(0.912)优于对数比例变换法(0.776);多波段模型法的反演平均绝对误差为1.47m,平均相对误差11.67%,均略低于对数比例变换法(1.45m,11.49%),但后者在小于1m的水深范围内的反演结果存在大范围错误,精度明显低于前者;多波段模型法可通过对回归方程和回归系数的显著性检验而不断优化,鲁棒性和适用性亦明显优于对数比例变换法。因此,本研究认为多波段模型法更适用于大量浅海水深快速反演流程化工作。     

测井数据分维计算及其应用条件研究

分形几何已成功地应用于储层表征,分维是储层一征和随机建模的控制参数,为了准确表征储层,必须精确地估计分维值。本文介绍了利用测井数据计算储层分维值的三种方法：变尺度分析法（Ｒ／Ｓ分析）,变异函数分析法、功率谱分析法,研究发现分维计算中对数据的分级处理实际上就是对数据进行灰色累加生成。研究表明影响分维估计精度的主要因素有四种：数据点数、数据概率分布、数据平稳性,无标度区,研究认为,现有的３种方法不能用