西藏尕尔穷—嘎拉勒铜金矿集区成矿规律、矿床模型与找矿方向

尕尔穷—嘎拉勒铜金矿集区位于西藏班公湖—怒江成矿带西段南缘的北冈底斯北侧,矿体类型丰富(斑岩型、矽卡岩型及铁氧化物铜金建造型),金品位较高(最高可达205g/t),构造位置独特,研究意义重大。通过对矿集区成矿地质条件的系统总结及对前人研究资料的系统分析,查明了矿石特征,发现了大量自然金、金属互化物,总结了成矿规律,认为成矿主要与晚燕山期侵位的石英闪长岩及花岗闪长岩有关,成岩与成矿之间演化时间在1Ma左右,区内矿化具有上铜金下钼的垂向分带特征,矿床S、Pb同位素显示成矿物质具有壳幔混合的源区特征。在准铝质-微弱过铝质钙碱性-高钾钙碱性岩浆岩的侵位、分馏演化过程中,在岩体隆起部位及其与白垩纪碳酸盐的内外接触带形成斑岩-矽卡岩型铜金(钼)矿体,在岩体边缘构造破碎带(F1断层)内形成铁氧化物铜金建造型矿体,由此建立了岩浆岩-地层-构造控制的斑岩-矽卡岩-铁氧化物铜金建造"三位一体"矿床模型。结合以上研究,提出矿集区应予以重视的找矿方向。     

重庆市国土房管信息安全体系规划和实施

随着我国政府及各行业信息化进程的不断推进,信息系统安全问题已经被提升到关系国家安全的战略性高度。本文结合信息系统安全等级保护和信息安全保障体系建设等方面的工作,从信息安全建设目标、原则和体系架构三个方面,阐述了重庆市国土房管信息安全体系总体规划,并从物理安全、网络安全、主机安全、数据安全和安全制度五个方面,介绍了信息安全体系建设的主要实施内容。     

资源三号卫星数据矿山地质环境调查研究

采矿引起的一系列矿山环境问题不仅威胁到人们生命财产安全,而且严重影响和制约着经济的发展,也引发了一系列社会问题和矛盾。本文运用资源三号卫星遥感数据,以黑龙江省鹤岗市为例,解译鹤岗市矿山地质环境,并对遥感图像解译成果进行综合分析研究。     

长春台不同类型地震的震相特征分析

通过对长春台CTS-1型宽频带地震计记录到的不同震中距及不同类型地震的波形进行分析,分别得出CTS-1型地震计所记录到的不同震中距及不同类型地震的震相特征。结果表明,每个类型的地震都各有自己的震相特征。     

Hot Air: University Climate Action Plans and Disarticulated Federalism

Individual states and academic institutions have taken leadership on climate change policy in the United States. Without unified national policy, a patchwork of state policies fosters geographic variation among climate action plans (CAPs) for American College and Universities Presidents’ Climate Commitment signatories. Correlation among indexes rating state climate policy and signatory CAPs and spatial analysis indicate that states with aggressive climate policy foster aggressive policy within their academies. Reflection on the national scale suggests that although state policies help combat climate change, they could be more significant if articulated within a more comprehensive national policy.     

MÉTHODE D'ÉTUDE DES NAPPES LIBRES DANS LES AQUIFÈRES ANISOTROPES

Abstract

The necessary and sufficient conditions for non-zero phase shift and non-zero attenuation in linear flood routing can be derived from the continuity equation alone and are found to depend on the existence of an imaginary part in the expression for frequency or in the expression for wave number. It is shown that in linear flood routing the phase lag between flow rate and area of flow is directly related to the attenuation per unit wave length. The effects of using various forms of the momentum equation, in addition to the continuity equation, are exemplified by deriving analytical expressions in terms of the frequency, both for attenuation per unit channel length and for phase shift, for the kinematic wave, the general diffusion analogy, and the complete St. Venant equation.     

Scholte waves on fluid-solid interfaces by means of an integral formulation

The present work shows the propagation of Scholte interface waves at the boundary of a fluid in contact with an elastic solid, for a broad range of solid materials. It has been demonstrated that by an analysis of diffracted waves in a fluid it is possible to infer the mechanical properties of the elastic solid medium, specifically, its propagation velocities. For this purpose, the diffracted wave field of pressures and displacements, due to an initial wave of pressure in the fluid, are expressed using boundary integral representations, which satisfy the equation of motion. The source in the fluid is represented by a Hankel’s function of second kind and zero order. The solution to this wave propagation problem is obtained by means of the Indirect Boundary Element Method, which is equivalent to the well-known Somigliana representation theorem. The validation of the results is carried out by using the Discrete Wave Number Method and the Spectral Element Method. Firstly, we show spectra of pressures that illustrate the behavior of the fluid for each solid material considered, then, we apply the Fast Fourier Transform to show results in time domain. Snapshots to exemplify the emergence of Scholte’s waves are also included.     

Implication of the flow resistance formulae on the prediction of flood wave propagation

ABSTRACT

This study examines the difference in the predictions of flood wave propagation in open channels depending on the flow resistance formulae, such as the Chézy and Manning’s equation. The celerity and diffusion coefficient are functions of the channel geometry, slope, roughness as well as the resistance formulae. The results suggest that substituting the Chézy equation with Manning’s equation results in different characteristics of flood propagation, which are consistent regardless of the cross-sectional geometry except for a circular cross-section: increasing celerity and decreasing diffusion coefficient. The celerity is more sensitive to the selection of resistance formulae than the diffusion coefficient. Geometry has a greater effect on the celerity and diffusion coefficient, and consequently on the resulting hydrographs. Manning’s equation results in a larger difference in celerity and diffusion coefficient compared to Chézy equation regardless of the water depth. Overall, this study shows that the selection of resistance formulae is important in terms of the resulting hydrographs and peak flow.

EDITOR Z.W. Kundzewicz ASSOCIATE EDITOR not assigned     

The distribution of Spearman’s rho trend statistic for persistent hydrologic data

Abstract

Spearman’s rho, a distribution-free statistic, has been suggested in the literature for testing the significance of trend in time series data. Although the use of the test based on Spearman’s rho (also known as the Daniels test) is less widespread than that based on Kendall’s tau (the Mann-Kendall test), the two tests have been shown in the literature to be equivalent for time series with independent observations. The distribution of the Mann-Kendall trend statistic for persistent data has been previously addressed in the literature. In this paper, the distribution of Spearman’s rho as a trend test statistic for persistent data is studied. Following the same procedures used for Kendall’s tau in earlier work, an exact expression for the variance of Spearman’s rho for persistent data with multivariate Gaussian dependence is derived, and a method for calculating the exact full distribution of rho for small sample sizes is also outlined. Approximations for moderate and large sample sizes are also discussed. A case study of testing the significance of trends in a group of world river flow station data using both Kendall’s tau and Spearman’s rho is presented. Both the theoretical results and those of the case study confirm the equivalence of trend testing based on Spearman’s rho and Kendall’s tau for persistent hydrologic data.

Editor Z. W. Kundzewicz; Associate editor S. Grimaldi     

Soil moisture assessment in the alluvial basins associated with seismic activity of northwest Anatolia,Turkey, using Landsat TM/ETM satellite imagery / Estimation de l’humidité du sol associée à l’activité sismique dans les bassins alluviaux du nord-ouest de l’Anatolie (Turquie) par l’imagerie satellitaire Landsat TM/ETM

Abstract

Abstract The aim of this study is to detect seasonal surface temperature changes and to estimate soil moisture conditions based on the evaporative cooling principle of damp ground in the alluvial basins of northwest Anatolia, Turkey, using Landsat TM/ETM data. According to analysis of satellite sensor data acquired on different dates, soil moisture is greatest in the spring season in the basins. Soil moisture decreases toward the summer and autumn. The 17 August 1999 earthquake occurred in the high surface temperature (low soil moisture) period, and the 12 November 1999 earthquake occurred in the low surface temperature (high soil moisture) period. It is possible to conclude that the urban-rural settlements and industrial developments on the loose deposits of the Adapazari, ?zmit and Düzce depressions have been affected by the seasonal changes in the local ground conditions.