承压水井水位固体潮扩散方程的解和含水层参数的求定

本文在求解承压水井水位固体潮的扩散方程时增加了井孔压力的边界条件，使扩散方程更符合实际情况，从而得到在理论上更为完善的起潮力位与水位固体潮之间的关系式。文中讨论了气压作用于承压含水层的水力扩散方程和气压对水位固体潮的影响。导出了相位滞后与含水层参数的解析式，为求解含水层数建立了基础。根据水位固体潮观测资料与气压观测资料，在给定地球模型的勒夫数的情况下，全面地解决了求定观测井含水层参数的方法。并给出     

广西桂平西山井水位同震特征和机理初探

收集了2008~2016年广西桂平西山井水位观测数据及全球5级以上地震资料,分析井孔记录水震波的能力、水震波形态特征及影响因素,初步探讨了西山井同震的机理,获得以下认识:桂平西山井对全球M_S≥7地震具有较好的同震响应能力,水震波的形态主要为振荡型,少数呈现阶升型。井-含水层观测系统、地震震级、井震距是影响井孔记录水震波能力的主要因素。含水层介质受瑞利面波作用会发生体积变化,导致水位振荡,是形成振荡型水震波的可能机理。阶变型水震波的形成与区域应力场增强、介质变化及构造活动等因素有关。西山井水位阶升与周边中强地震活动存在较好对应关系,该认识可为地震预测研究提供参考。     

无压含不层非稳定流诱发地壳形变的定量计算

基于无压含水层迟后疏干的Ｂｏｕｌｔｏｎ理论，导出地下水无压水层完整井非稳定流单井排放诱发的地表位移的解析表达式，讨论了公式的计算方案，给出了模拟计算实例。     

横向各向同性(VTI)介质中非线性地震波场模拟

数值计算方法是考察非线性弹性波在介质中（如岩石）传播特征的重要手段.非线性弹性波的数值模拟存在陡峭间断面（点）、数值振荡以及误差的指数级增长等现象而破坏数值解的稳定性、收敛性，能否消减上述现象的不利影响成为制约数值方法有效与否的重要因素.文中同时引入了FCT算子和幅值限制器，采用中心差分格式对具有垂直对称轴的横向各向同性（VTI）介质中的二维非线性弹性波进行数值模拟，从而克服了上述困难；介绍了适用于非线性弹性波的吸收边界条件，给出了差分方程的稳定性条件.在验证了方法的有效性后成功地获取了二维VTI介质中非线性弹性波的三分量地震正演记录，表明非线性波在传播过程中会发生波形畸变等现象.     

水位波动信息在含水层中传播特性的实验研究

本文通过一系列水动力学模型实验，探讨了水位波动信息在含水层中传播的特性。实验结果表明，水位波动信息在含水层中传播时发生幅度衰减、时间滞后乃至形态变异等复杂现象，其特征同含水介质的类型、波动信息的频率与传播距离等有关。这样的结果，对地下水位映震条件、映震特征与映震机制的深入研究，提供了有益的启示。     

深井水位对固体潮和气压的响应

本文以体应变固体潮对深井水位影响的偏微分方程为基础，考虑到含水层与井孔之间相互渗流的边界条件，用叠加原理、冲量定理的分离变量等方法得出了方程的解。把水井含水层的参量给予一些可能的值，通过数值计算讨论了水井固体潮系数、位相滞后和含水层参数之间的关系，解释了井水位对固体潮响应的位相滞后现象。结果表明，井孔的半径、含水层的孔隙度及固体骨架的体压缩系数愈大，含水层的导水系数愈小，则水井水位的固体潮系数愈小     

离散介质中地震波传播的数值模拟

伪谱法应用付里叶变换和有限差分求解波动方程，本利用伪谱法模拟了三维离散介质中地震波的传播。结果表明：(1)该方法的计算精度高；(2)即使在均匀、各向同性的离散介质中，地震波的传播也表现出方位各向异性的特点。     

水井含水层导水系数及其对地震波的响应

利用弹性理论和渗流理论研究了井水位振荡试验,给出了一种计算水井含水层渗流特性参数的新方法。该方法不是用井水位的恢复曲线,而是用井水位的振荡曲线计算出水井含水层的导水系数。对５ 口水井的导水系数及其对地震波的响应进行了统计,结果表明：水井含水层的导水系数越大,井水位对地震波响应的幅度越大,响应的次数越多。     

定水头注水引起的含水层水平运动和应变

基于含水层固体颗粒与孔隙水不可压缩的假设，本文导出了单井注水情况下秦斯承压含水层水平运动速度与水头之间的基本关系式。然后利用注水井壁处的应力、应变边界条件，进一步导出了单井定水头注水引起的泰斯承压含水层水平运动速度、位移和应变解析表达式。该水平位移与应变由两部分组成：一部分为由注水压力本身引起的经典弹性力学解项，它仅随半径而变化，与注水时间无关；另一部分为由地下水头变化引起的水动力学位移和应变解项。其中，含水层水动力学水平位移随时间加长呈指数增长特征、水动力学径向应变则表现为近井处拉张、远井处挤压的分区特征，且近井拉张区随时间加长逐渐向外扩展。单井注水含水层水动力学水平位移、应变解的导出，完善和发展了单孔内压经典弹性平面力学问题解。     

含水层渗透性能变化对水位影响的数值模拟研究

应用有限差分法,对弹性孔隙介质在无水平应力作用情况下的充水过程和充水稳定后部分区域阻塞情况下水头调整过程进行了分析。研究结果显示:就含水层内某一点而言,其水头除与位置和含水层的边界条件有关外,还与它本身及其周围区域的压力传导系数有关;含水层不同程度的阻塞会引起给定点的水位变化,而且不同的阻塞范围对含水层的水头分布和给定点的水头变化有很大的影响。     

Theoretic analysis on phase delay phenomena of well water level tide in the double medium aquifer model

Introduction The phenomenon of water level tide was discovered at Duchort diggings, Czech in 1879. By 1939, Theis, an America hydrogeologist, confirmed that periodical wave of the well water level is caused by the solid tide. In 1964, Melchior, a Belgium geophysist, began to make research on this phenomenon. Then Cooper (1965), Bredehoeft (1967) and WANG, et al (1988) followed. In China the study on water level tide began with 1970s, and the study on well water level phase lagging began …     

地下水潮汐现象的物理机制和统一数学方程

用新的分层承压含水层模式 ,不但考虑含水层的力学压缩性质 ,而且考虑含水层的渗流特性 ,并结合扰动信息源的频率特性 ,分别研究扰动源地球固体潮、大气潮和地表负荷潮对承压井水位和流量的影响机理 ,给出相应的偏微分方程。从方程的解释或数值解讨论扰动源与承压井含水层的力学压缩参数、渗流特性参数及与频率特性频数的关系 ,进而给出承压井水位和流量对地球固体潮、大气潮和地表负荷潮汐响应的统一数学方程及其潮汐响应函数 ,并揭示了上述几类潮汐扰动信息源对承压井水位和流量影响的物理机理     

中国地下水潮汐的观测研究和分析

本文简单介绍了中国地下水潮汐的观测研究情况,介绍了对承压水位潮汐机理研究的理论结果,给出了固体潮体应变、气压和海洋潮汐对承压水头影响的偏微分方程,从这些方程的简化解讨论了它们与含水层参数间的关系.并从全国选取了33口有代表性的井孔,对这些井孔的水位和气压观测资料采取反复调和分析的方法,求出了它们的水位固体潮体应变各分波的潮汐系数和位相滞后,也求出了水位气压各分波的系数和位相滞后.      

深井水位的固体潮效应

本文从体应变固体潮对深井水位影响的偏微分方程出发,考虑到含水层和井孔之间相互渗流的边界条件,用叠加原理、冲量定理和分离变量法等方法得出了方程的解.通过对这个解中水井含水层参数给予一些可能的值进行数值计算,讨论了水井固体潮系数和位相滞后与水井含水层参数间的关系,较好地解释了井水位对固体潮响应的位相滞后现象.计算表明,井孔的半径、含水层的孔隙度及固体骨架的体压缩系数愈大,含水的导水系数愈小,则水井水位的固体潮系数愈小,而水位对固体潮响应的位相滞后愈大.井水对长周期的潮汐响应比对短周期的更好.      

Beitrag zur analytischen Beschreibung von Transportprozessen im Grundwasserleiter bei diffusem Stoffeintrag

A model is described for the relation between water quantity and water quality in the aquifer with the diffuse substance input by the gravitation water being taken into account. The model is based on a partial differential equation of the second order for a flow pipe. For constant transport parameters, a sink of the kinetics of the first order and a time-dependent source term an exact analytical solution is presented and explained by a model. At a diffuse substance input, the dispersion has only a slight influence on the transport of substances contained in water. Potential applications of these solutions to different problems are mentioned.     

线弹性含水层井水位、孔压对引潮位响应的研究及其应用

应用线弹性介质力均衡方程,研究不排水条件下饱水岩体在潮汐力作用下的体应变,提出了承压含水层孔压对引潮高的线性响应方程,并给出了该方程响应系数(E)的物理意义.结合Hsieh 等(1987)提出的井水位对孔压响应的振幅比(A)和位相差(α1)公式,进一步推导出了井水位-引潮高振幅比M=EA和位相差α=α1+α2公式.M和...     

A double-porosity model for a fractured aquifer with non-Darcian flow in fractures

Abstract

Non-Darcian flow in a finite fractured confined aquifer is studied. A stream bounds the aquifer at one side and an impervious stratum at the other. The aquifer consists of fractures capable of transmitting water rapidly, and porous blocks which mainly store water. Unsteady flow in the aquifer due to a sudden rise in the stream level is analysed by the double-porosity conceptual model. Governing equations for the flow in fractures and blocks are developed using the continuity equation. The fluid velocity in fractures is often too high for the linear Darcian flow so that the governing equation for fracture flow is modified by Forcheimer's equation, which incorporates a nonlinear term. Governing equations are coupled by an interaction term that controls the quasi-steady-state fracture—block interflow. Governing equations are solved numerically by the Crank-Nicolson implicit scheme. The numerical results are compared to the analytical results for the same problem which assumes Darcian flow in both fractures and blocks. Numerical and analytical solutions give the same results when the Reynolds number is less than 0.1. The effect of nonlinearity on the flow appears when the Reynolds number is greater than 0.1. The higher the rate of flow from the stream to the aquifer, the higher the degree of nonlinearity. The effect of aquifer parameters on the flow is also investigated. The proposed model and its numerical solution provide a useful application of nonlinear flow models to fractured aquifers. It is possible to extend the model to different types of aquifer, as well as boundary conditions at the stream side. Time-dependent flow rates in the analysis of recession hydrographs could also be evaluated by this model.     

Effect of earth tide on deep well water level

On the basis of the partial differential equations of the water level in a deep well that is affected by the bulk strain tide, the boundary conditions of permeating each other between aquifer and well are considered. The solutions of the equations have been obtained by the superposition principle, inpulse theorem and separation of the variations. Some suitable values are given to the parameters of well aquifer in the solutions. By means of the numerical calculation the relations among the well tide coefficients and phase lag phenomenon of response of the well level to earth tides is well interpreted. The parametric studies and the obtained graphs show that the more the radius of casing in a well, the porosity of an aquifer and the bulk compressibility for solid matrix of an aquifer, the less the transmissibility of an aquifer, then the less the tidal coefficient of well level, while the more the phase lag for well level to respond to the tide is. The response of the well level to the tide of longer period is better than the shorter period events. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 66–75, 1991.     

A quasi three-dimensional model for flow and transport in unsaturated and saturated zones: 1. Implementation of the quasi two-dimensional case

A quasi three-dimensional (QUASI 3-D) model is presented for simulating the subsurface water flow and solute transport in the unsaturated and in the saturated zones of soil. The model is based on the assumptions of vertical flow in the unsaturated zone and essentially horizontal groundwater flow. The 1-D Richards equation for the unsaturated zone is coupled at the phreatic surface with the 2-D flow equation for the saturated zone. The latter was obtained by averaging 3-D flow equation in the saturated zone over the aquifer thickness. Unlike the Boussinesq equation for a leaky-phreatic aquifer, the developed model does not contain a storage term with specific yield and a source term for natural replenishment. Instead it includes a water flux term at the phreatic surface through which the Richards equation is linked with the groundwater flow equation. The vertical water flux in the saturated zone is evaluated on the basis of the fluid mass balance equation while the horizontal fluxes, in that equation, are prescribed by Darcy law. A 3-D transport equation is used to simulate the solute migration. A numerical algorithm to solve the problem for the general quasi 3-D case was developed. The developed methodology was exemplified for the quasi 2-D cross-sectional case (QUASI2D). Simulations for three synthetic problems demonstrate good agreement between the results obtained by QUASI2D and two fully 2-D flow and transport codes (SUTRA and 2DSOIL). Yet, simulations with the QUASI2D code were several times faster than those by the SUTRA and the 2DSOIL codes.