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111.
以映射和叠加原理为基础,探讨了均质、等厚承压含水层中地下水向完整井作三维运动时,地下水稳定运动基本微分方程的求解方法,并与裘布衣公式作了对比。由于求解时考虑了地下水流速的水平、垂直分量,故所得结果较裘布衣公式更为准确与合理。 相似文献
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115.
地质雷达及其在环境地质中的应用 总被引:24,自引:2,他引:24
本文结合近几年联邦德国在环境地质方面的研究工作对地质雷达在环境工程领域中的应用范围及其局限性作了简要总结,文中并介绍了地质雷达技术的方法原理及存在问题。 相似文献
116.
Water is the most active component in all geological systems.It has an important effect on the physical properties of minerals and melts.It also plays a key role in the evolution of the Earth.Accurate thermodynamics data on water are currently confined to pressures below 1.0GPa and temperatures below 900℃.Presented in this paper are new data available on the P-T properties of water at pressures up to 5.0GPa,develoged from differential thermal analysis and ultrasonic wave amplitude analysis.It has been found that there may exist another ternary point at 3.0GPa and that ultrasonic wave amplitude change of ice-water transition shows two inflection points above 2.0GPa, consistent with the two peaks of differential thermal curves above 2.0GPa .It may be a new phenomenon which needs further study. 相似文献
117.
采用RAMAC/GPR探地雷达对机场跑道传力杆进行探测试验,取得了令人满意的效果,为机场工程质量检测提供了一种有效手段。 相似文献
118.
This paper addresses the problem of characterizing the shape of a geological surface on the basis of its principal curvatures.
The surface is assumed to be modeled as a set of adjacent triangles defined by the location of their vertices and a method
is proposed for estimating numerically the principal curvatures at the vertices of the triangles using a local C2 interpolant. Also shown is how principal curvatures can be useful for studying the deformation of a geological surface (with
application to 3D balanced unfolding), and analyzing the folding or faulting of the interface between two adjacent layers. 相似文献
119.
Jürg W. Schlatter Alfred Wüest Dieter M. Imboden 《Aquatic Sciences - Research Across Boundaries》1997,59(3):225-242
The artificial tracer sulphur hexafluoride (SF6) has been used to study the density-driven deep water exchange between two sill-separated basins of Lake Lucerne, Gersauersee and Urnersee. The sources of the density gradients between the two basins are (1) salinity differences between the major inlets due to the different geology of their drainage areas, and (2) temperature differences due to spatial variation of wind forcing. Wind speeds are generally larger in Urnersee, especially in spring during the so-called Föhn events, when winds blow from the south. In contrast, Gersauersee is protected form these winds. In spring 1989, a total of 630 g of SF6 was released at 80 to 120 m depth in the small Treib Basin located between Urnersee and Gersauersee. During about 100 days the distribution of SF6 in the lake was determined by gaschromatography. Two models are used to quantify the exchange flow, (1) a one-box mass balance model for SF6 in the deep part of Treib Basin, and (2) a one-dimensional diffusion/advection model describing the temporal and vertical temperature variation in Urnersee. According to the first model, the flow into the deep hypolimnion of Urnersee, decreases from 21·106 m3·d?1 at the end of March to about 8·106 m3·d?1 in late April. The second model yields similar flow rates. The decrease of the flow rate during spring, confirmed by both approaches, is consistent (1) with the decreasing strength of the density gradient above the sill during spring and early summer, and (2) with hydrographic information collected in Lake Lucerne during other years. 相似文献
120.
从综合地层学观点论华南浅海相泥盆系—石炭系的分界 总被引:1,自引:0,他引:1
生物地层学、事件地层学和层地层学综合研究表明,华南浅海相区与Siphonodellapraesulcata带和S.sulcata带之间的界线相当的泥盆系-石炭系的界线不仅高于Cystophrentis带楔界,而且还应高于引起Cystophrentis绝灭的海退事件层的顶界。 相似文献