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1.
The structure, functioning and hydrodynamic properties of aquifers can be determined from an analysis of the spatial variability of baseflow in the streams with which they are associated. Such analyses are based on simple low‐cost measurements. Through interpreting the hydrological profiles (Q = f(A)) it is possible to locate the aquifer(s) linked to the stream network and to determine the type of interrelated flow, i.e. whether the stream drains or feeds the aquifer. Using an analytical solution developed for situations with a positive linear relationship, i.e. where the baseflow increases linearly with increasing catchment size, it is also possible to estimate the permeability of the aquifer(s) concerned at catchment scale. Applied to the hard‐rock aquifers of the Oman ophiolite, this method shows that the ‘gabbro’ aquifer is more permeable than the ‘peridotite’ aquifer. As a consequence the streams drain the peridotites and ‘leak’ into the gabbro. The hydrological profiles within the peridotite are linear and positive, and indicate homogeneity in the hydrodynamic properties of these formations at the kilometre scale. The permeability of the peridotite is estimated at 5 · 10?7 to 5 · 10?8 m/s. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
2.
D. Prandle 《Estuarine, Coastal and Shelf Science》1985,20(5):615-635
An examination is made of the circulation in narrow estuaries subject to a predominant tidal forcing. Velocity structures are derived separately for residual flow components associated with (a) river flow, (b) wind stress, (c) a well-mixed longitudinal density gradient and (d) a fully stratified saline wedge. Dimensionless parameters are introduced to indicate the magnitude of each component and these parameters are evaluated for 9 major estuaries, thereby revealing their sensitivity to each component.For a channel of constant breadth and depth, formulae are deduced for the length of saline intrusion, L. Comparisons with observed data show that such formulae may be used with confidence to predict changes in L arising from variations in river flow, tidal range or channel depths.The level of stratification is shown to be related to a product of two parameters, one associated with velocity structure and a second involving the square of the ‘flow ratio’ (i.e. residual velocity/amplitude of the tidal velocity). This relationship provides a simple classification system for estuarine stratification which can be used to indicate the sensitivity of any particular estuary to changing conditions. 相似文献
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提出用B样条函数求解曲线、曲面上重磁位场的向上延拓,水平、垂向导数计算,磁异常分量互换的方法。该方法的特点是:原理简明,程序通用性强,计算精度高。 相似文献
5.
应用探地雷达探测活动断层 总被引:1,自引:0,他引:1
在浅覆盖区采用探地雷达探测地震活动断层。通过实验确定出最佳的采集参数和数据处理流程,在雷达剖面上,能够清晰地显示出断层上部的形态特征、上断点埋深和岩土分层。结合钻孔资料,利用雷达剖面上对第四系覆盖的分层结果和上断点所在的层位可以分析和评价断层的活动性。 相似文献
6.
Assessment of sand encroachment in Kuwait using Geographical Information System (GIS) technology has been formulated as a
Multi-Criteria Decision Making problem. The Delphi method and Analytical Hierarchy Process were adopted as evaluating techniques,
in which experts’ judgments were analyzed for objectively estimating and weighting control factors. Seven triggering factors,
depicted in the form of maps, were identified and ordered according to their priority. These factors are (1) wind energy;
(2) surface sediment; (3) vegetation density; (4) land use; (5) drainage density; (6) topographic change and (7) vegetation
type. The factor maps were digitized, converted to raster data and overlaid to determine their possible spatial relationships.
Applying a susceptibility model, a map of sand encroachment susceptibility in Kuwait was developed. The map showed that the
areas of very high and high sand encroachment susceptibility are located within the main corridor of sand pathway that coincides
with the northwesterly dominant wind direction. 相似文献
7.
The Dahuiyeh (Zarand) earthquake of 2005 February 22 in central Iran: reactivation of an intramountain reverse fault 总被引:3,自引:0,他引:3
8.
从118.75 GHz附近六通道亮温反演大气温度廓线的数值模拟研究 总被引:5,自引:0,他引:5
为了能在静止气象卫星上实现微波被动遥感探测大气温度廓线,并保持一定的地面空间分辨率(如视场小于60 km),就需要使用高频微波及大天线.欧洲和美国下一代静止气象卫星上都已考虑采用118.75 GHz附近通道.为了充分了解118.75 GHz附近通道遥感反演温度廓线的能力,为仪器研制及今后资料的解释反演提供必要的基础数据,作者开展了采用118.75 GHz附近六个通道遥感反演大气温度廓线的数值模拟研究.统计反演的数值试验表明,118.75 GHz附近六通道对温度垂直分布有一定的遥感反演能力;温度反演较好的层次对应于权重函数峰值所在的位置. 相似文献
9.
高陵-达县剖面位于秦岭中段,斜跨中朝准地台、秦岭褶皱系、扬子准地台三大构造单元。在研究剖面实磁场特征的基础上,综合地质、物性、省内及邻省深部物探资料,建立了剖面地质-地球物理模型,依此对剖面通过地段的地壳结构、断裂带深部特征、三大构造单元的深部格架进行了解释推断。 相似文献
10.
茅台酒酿酒高梁的地质环境研究 总被引:2,自引:0,他引:2
茅台酒对酿酒高梁有严格要求,适于茅台酒传统酿造工艺的高梁只产于仁怀县的某些地区,主要是受地质环境的控制。仁怀高梁对某些常量和微量元素有着鲜明的选择性,对磷和钼表现出强烈的吸收作用。岩-土剖面元素的迁聚,对磷和铝的供应是确定仁怀高梁品质和产量的关键。侏罗系砂泥岩、二叠系煤系地层的岩-土剖面,元素淋溶微弱,总量丰富,有效态含量高,组合良好,能正常进行岩-土-高梁系统的物质转化与元素迁移,能充分供应高梁生长所需的磷和钼等元素,是茅台酒酿酒高梁的最宜种植区。 相似文献