Urban fluvial flood modelling using a two‐dimensional diffusion‐wave treatment,part 2: development of a sub‐grid‐scale treatment

This paper develops and tests a sub‐grid‐scale wetting and drying correction for use with two‐dimensional diffusion‐wave models of urban flood inundation. The method recognizes explicitly that representations of sub‐grid‐scale topography using roughness parameters will provide an inadequate representation of the effects of structural elements on the floodplain (e.g. buildings, walls), as such elements not only act as momentum sinks, but also have mass blockage effects. The latter may dominate, especially in structurally complex urban areas. The approach developed uses high‐resolution topographic data to develop explicit parameterization of sub‐grid‐scale topographic variability to represent both the volume of a grid cell that can be occupied by the flow and the effect of that variability upon the timing and direction of the lateral fluxes. This approach is found to give significantly better prediction of fluvial flood inundation in urban areas than traditional calibration of sub‐grid‐scale effects using Manning's n. In particular, it simultaneously reduces the need to use exceptionally high values of n to represent the effects of using a coarser mesh process representation and increases the sensitivity of model predictions to variation in n. Copyright © 2005 John Wiley & Sons, Ltd.     

Gypsies in the palace: experimentalist's view on the use of 3‐D physics‐based simulation of hillslope hydrological response

As a fundamental unit of the landscape, hillslopes are studied for their retention and release of water and nutrients across a wide range of ecosystems. The understanding of these near‐surface processes is relevant to issues of runoff generation, groundwater–surface water interactions, catchment export of nutrients, dissolved organic carbon, contaminants (e.g. mercury) and ultimately surface water health. We develop a 3‐D physics‐based representation of the Panola Mountain Research Watershed experimental hillslope using the TOUGH2 sub‐surface flow and transport simulator. A recent investigation of sub‐surface flow within this experimental hillslope has generated important knowledge of threshold rainfall‐runoff response and its relation to patterns of transient water table development. This work has identified components of the 3‐D sub‐surface, such as bedrock topography, that contribute to changing connectivity in saturated zones and the generation of sub‐surface stormflow. Here, we test the ability of a 3‐D hillslope model (both calibrated and uncalibrated) to simulate forested hillslope rainfall‐runoff response and internal transient sub‐surface stormflow dynamics. We also provide a transparent illustration of physics‐based model development, issues of parameterization, examples of model rejection and usefulness of data types (e.g. runoff, mean soil moisture and transient water table depth) to the model enterprise. Our simulations show the inability of an uncalibrated model based on laboratory and field characterization of soil properties and topography to successfully simulate the integrated hydrological response or the distributed water table within the soil profile. Although not an uncommon result, the failure of the field‐based characterized model to represent system behaviour is an important challenge that continues to vex scientists at many scales. We focus our attention particularly on examining the influence of bedrock permeability, soil anisotropy and drainable porosity on the development of patterns of transient groundwater and sub‐surface flow. Internal dynamics of transient water table development prove to be essential in determining appropriate model parameterization. Copyright © 2010 John Wiley & Sons, Ltd.     

Geological evolution and structural style of the Palaeozoic Tafilalt sub‐basin,eastern Anti‐Atlas (Morocco,North Africa)

The Tafilalt is one of a number of generally unexplored sub‐basins in the eastern Anti‐Atlas of Morocco, all of which probably underwent a similar tectono‐stratigraphic evolution during the Palaeozoic Era. Analysis of over 1000 km of 2‐D seismic reflection profiles, with the interpretation of ten regional seismic sections and five isopach and isobath maps, suggests a multi‐phase deformation history for the Palaeozoic‐aged Tafilalt sub‐basins. Extensional phases were probably initiated in the Cambrian, followed by uniform thermal subsidence up to at least the end of the Silurian. Major extension and subsidence did not begin prior to Middle/Upper Devonian times. Extensional movements on the major faults bounding the basin to the north and to the south took place in synchronisation with Upper Devonian sedimentation, which provides the thickest part of the sedimentary sequence in the basin. The onset of the compressional phase in Carboniferous times is indicated by reflectors in the Carboniferous sequence progressively onlapping onto the Upper Devonian sequence. This period of compression developed folds and faults in the Upper Palaeozoic‐aged strata, producing a structural style characteristic of thin‐skinned fold and thrust belts. The Late Palaeozoic units are detached over a regional décollement with a northward tectonic vergence. The folds have been formed by the process of fault‐propagation folding related to the thrust imbricates that ramp up‐section from the décollement. Copyright © 2007 John Wiley & Sons, Ltd.     

平顶山矿区塌陷地分区利用探究

土地资源日益紧缺的今天,矿区塌陷地也是一种重要的土地资源,对其利用要在空间上进行科学的规划和合理的布局。土地分区利用原理使我们对矿区塌陷地的利用由盲目的农业复垦而转到自觉的进行区位选择上来。文章根据平顶山矿区塌陷地的自然特点和塌陷状况,将塌陷区划分成4个不同的区域,从而进行分区利用,使矿区塌陷地的利用符合其区位特征,从而实现塌陷地区位效益。     

沈阳市连续运行卫星定位服务系统的建立与运行

从连续运行卫星定位服务系统的关键技术、功能组成、坐标联测,以及测试等方面出发,介绍了沈阳市连续运行卫星定位服务系统（SYCORS）的建立与运行情况,并对系统建立和运行过程中的主要经验进行了介绍,以资借鉴。     

Biases of submerged bulk and freeze‐core samples

Freeze‐coring and bulk sampling are routine methods used to sample subsurface spawning gravel under shallow water. Both methods have limitations. Freeze‐coring is not believed to representatively sample coarse grain sizes and the sample volumes are relatively small. Conversely, when bulk sampling, even within an enclosure, some fine sediment is suspended and washed away from the sample. This paper assesses the biases in sampling performance between the two methods and determines whether the loss of fines that occurs when bulk sampling could be predicted and thus corrected for. At six riffles the spawning substrate was sampled under approximately 50 cm of water with a bulk sample and three adjacent freeze‐cores. For each riffle, data from the two samples were combined using the method of Fripp and Diplas (1993) and the resultant composite sample was compared with the original freeze‐core and bulk samples to assess the relative precision and biases of the two techniques. On average, the D<sub>50sub> of the bulk samples was 4 mm larger and a one‐third loss of the <2 mm fraction occurred compared with the composite samples. In contrast, freeze‐core samples contain on average 32% more sediment >16 mm compared with composite samples. Based on six samples, taken from six riffles, the amount of sediment finer than 0·5 mm lost using our bulk sampling technique with an enclosure appears to be predictable and correctable. Copyright © 2005 John Wiley & Sons, Ltd.     

基于遥感与地理信息系统的SRM融雪径流模型在Alps山区流域的应用

融雪水在水资源利用中扮演着及其重要的角色，遥感技术的发展使得大面积监测雪盖成为河能，选择Alps意大利境内的Rienza流域，利用SRM模型模拟春季融雪径流，区别传统对SRM模型的描述，参数选择和应用的研究方式，研究环境因素对这些参数的影响尤其是对度-日因子的影响以及它们之间的内在关系，重点讨论利用GIS和遥感数据获取SRM模型中的关键参数和因子，结论显示SRM模型模拟春季融雪径流的关键是精确地输入模型参数；遥感数据在提取雪盖面积的过程中，消除地形影响是必要的；从SRM模型的应用状况分析，精确地获取雪盖面积是影响模拟结果的关键。     

永泰地区早白垩世深成岩体的划分及形成环境

永泰序列系复式深成岩体，由4个深成岩体、48个侵入体组成。按岩石谱系单位可划分为3个单元、2个独立单元及若干个亚单元。其形成时代为早白垩世，属同熔型花岗岩类。岩体受北北西向及北东东向断裂控制，为拉张环境下被动就位。     

挠性钻杆的研制

挠性钻杆是实现高精度定向钻孔技术的关键器具之一。介绍了国内外技术发展简况，设计中的主要技术关键，主要技术规格，结构与组成。并对其进行了性能检测，证明其中的挠性接头具有足够大的抗拉、压、扭能力。     

Diurnal and Subdiurnal Terms in Rdan97 Series

In this paper, the series RDAN97 recently published (Roosbeek and Dehant, 1998) is completed by computing the diurnal and subdiurnal nutation terms. The method used is based on computing the torque induced by the external bodies on the rigid earth. The ephemerides used are analytical and based on celestial mechanics considerations. With a truncation level of 0.1 μas, 115 terms in longitude and 78 terms in obliquity have been computed. These terms correspond to the influence of the earth's geopotential coefficients c<sub>2,2sub> and s<sub>2,2sub>, c<sub>3,msub> and s<sub>3,msub> (for the interaction between the earth and the moon and the sun), and c<sub>4,msub> and s<sub>4,msub> (for the interaction between the earth and the moon). A comparison with the recent theories REN‐2000 (Souchay and Kinoshita, 1996, 1997) and SMART97 (Bretagnon et al., 1997, 1998) shows that our series is at a very high precision, better than the most recent VLBI campaigns. This revised version was published online in July 2006 with corrections to the Cover Date.