Long-Term Variability of Natural Groundwater Resources in the Moscow Region

A tendency to an increase in groundwater resources, which is associated with changes in the climatic and technological situation in the catchment areas, is traced. It is shown that the degree of disturbance of groundwater runoff regime should be taken into account when assessing and mapping the groundwater resources. An example of assessing the minimal mean monthly natural groundwater resources of a 95-% probability in the Moscow Region is considered.     

利用水位资料反演华北地区构造应力场变化

本文选取华北地区观测条件较好的63口水位观测井资料, 运用小波分析法去除各井水位资料中的短期高频信息, 提取出能反映水位多年动态变化的趋势信息, 并利用各井水位趋势变化数据反演出华北地区多年构造应力场变化图像, 结合其它水文资料, 探讨了华北地区近年来的构造应力场变化特征。     

大同—阳高地震前山西地下水动态异常

山西井网建成观测以来,首次遇到强震群,工作表明震前水动态有短期与临震异常,该资料具有参考价值。     

1989年大同—阳高6.1级地震地下水动态异常特征

对1989年10月大同—阳高地震地下水动态异常的中短期、临震及震后效应等多方面的特征进行了总结。说明了地下水异常形态的多样性、动态水位异常井多井次成组异常的同步性、多井次临震异常在时间、形态上的一致性。     

Regularities in the Spatiotemporal Variations of Deformation Processes in the Region of Japan Subduction Zone

Izvestiya, Physics of the Solid Earth - The approach is proposed for modeling deformations in the subduction zones from the surface displacement data recorded by the methods of satellite geodesy....     

Groundwater interaction assessment based on the large-scale mapping of geological and hydrogeological conditions in Moscow

Assessing the interaction between aquifers is crucial for estimating the extent of protection of the aquifer in Carboniferous limestone (which is the main source of potable water supply to Moscow area) against contaminants penetrating from the overlying aquifers. The presented approach to assessing groundwater interaction and protection is based on large-scale mapping of the geological and hydrogeological conditions in Moscow. The obtained results may be used for solving the problem of groundwater protection against contamination, as well as for planning the engineering activities in the city.     

Identification and Explanation of a Change in the Groundwater Regime using Time Series Analysis

Time series analysis is applied to identify and analyze a transition in the groundwater regime in the aquifer below the sand ridge of Salland in the Netherlands, where groundwater regime refers to the range of head variations throughout the seasons. Standard time series analysis revealed a discrepancy between modeled and observed heads in several piezometers indicating a possible change in the groundwater regime. A new time series modeling approach is developed to simulate the transition from the initial regime to the altered regime. The transition is modeled as a weighted sum of two responses, one representing the initial state of the system, the other representing the altered state. The inferred timing and magnitude of the change provided strong evidence that the transition was the result of significant dredging works that increased the river bed conductance of the main river draining the aquifer. The plausibility of this explanation is corroborated by an analytical model. This case study and the developed approach to identify a change in the groundwater regime are meant to stimulate a more systematic application of time series analysis to detect and understand changes in groundwater systems which may easily go unnoticed in groundwater flow modeling.     

Simulation of Groundwater Level in Ephemeral Streams with an Improved Groundwater Hydraulics Model

As a component of arid ecosystems, groundwater plays an important role in plant growth; therefore, it is essential to use deterministic models to reconstruct the process of groundwater level change. Typically, the linearized solution of the one-dimensional (1-D) Boussinesq equation yields acceptable performance in simulating transient conditions over short recharge periods in ephemeral stream systems, but the ability of this solution to simulate multiyear changes in groundwater levels is limited. In this study, an improved groundwater hydraulics (GH-D2) model is built based on the groundwater hydraulics (GH) solution of the 1-D Boussinesq equation to simulate multiyear changes in the groundwater level in ephemeral stream systems. The model is validated in the lower reaches of the Tarim River to simulate groundwater level fluctuations within the scope of influence of the river (300, 500, 750, 1050 m) over a 16-year period (2000 to 2015). To evaluate the performance of the models, the bias, mean absolute error, root mean squared error, Nash-Sutcliffe efficiency (NSE), and coefficient of determination (R²) are calculated. The results show that the improved GH-D2 model, which considers ephemeral streamflow, unsteady flow theory and the delayed response effect of groundwater level changes, performs well in simulating multiyear changes in the groundwater level in the ephemeral stream system. The observed and simulated values of the groundwater level at different river distances are consistent, and the model provides a new basis for multiyear simulations of groundwater level fluctuations in ephemeral stream systems.     

Formation of High-Alkali Groundwater in Upper Aquifers

Generalized observational data on groundwater chemistry and the results of modeling geochemical processes allowed us to establish that the formation of high-carbonate alkaline waters follows two ways, i.e., calcium and soda. It is shown that the formation of alkaline waters in semiarid and arid zones can be facilitated by acid atmospheric precipitation, which forms the concentration of Ca in groundwater sufficiently high to initiate ion exchange processes resulting in the formation of H₂CO₃–Na waters. Ion exchange is shown to be a boundary process, which facilitates the transition from calcium to soda way of groundwater metamorphization with subsequent increase in the carbonate content and alkalinity of groundwater.     

地下水位变化对金州水准基岩标石的影响分析

对辽宁金州地震台地下水位上升引起水准基岩标石底部岩层的应力变化进行定性和定量分析,并使用分层总和法计算基岩标石受到的影响量.研究结果表明,金州水准所受地下水的干扰,主要是标石底部的基岩在地下水位变化的作用下而发生形变所致,其影响的大小与水位变化幅度、水容重、基岩的压缩模量和孔隙度有关.     

Complex Isotopic and Hydrogeochemical Studies of Groundwater in the Kirov Region

Uranium-isotopic and multi-element hydrogeochemical methods are used to assess the natural pollution of fresh groundwater in horizons under development due to a modern intrusion of hypogene water with increased boron and fluorine contents in zones of old tectonic dislocations. The total index of the abovestandard (>MAC) pollution of groundwater in the region of the city of Kirov (the Kirov area) reaches 15. To reduce the effect of natural groundwater pollutants on the health of population, it is recommended that the groundwater intake should be regulated, purifiers should be used, and prospects revealed by the isotopic-and-hydrogeochemical data should be explored. The feasibility of modeling the groundwater formation and tracing the neotectonic dislocations in geological platforms is shown.     

Spatial and Temporal Variations in the Formation of the Kamennaya Steppe Water Regime

The processes of water regime formation in the catchment areas of deans in the Kamennaya Steppe are studied based on the data of many-year field experiments. Certain regular variations are recognized in the characteristics of the Kamennaya Steppe hydrological and ecological condition and their correlation with anthropogenic and climatic factors is established.     

Features of the Balance Structure Formation of Groundwater Withdrawal and Its Effect on River Flow at a Subsoil Water Level Drawdown

Water Resources - The balance structure of the pumpage sourses of riverside water-intakes, developing a subsoil aquifer or intermediate water that hydraulically interacts with it, can show the...     

山西及邻区地下水位中短期异常识别标志及预报方法研究

采用了“九五”地震科技攻关地下水物理及 EIS2 0 0 0提供的多种数据处理方法 ,对山西省及邻近地区的地下水位观测资料进行了处理 ,筛选出较好的数据处理方法和异常指标。研究结果表明 ,适应于地下水位数据处理的方法有模糊数学从属函数法及水位变差法 ,得出如下结论 :模糊数学从属函数法的原始数据大于 2倍均方差、从属函数 μ≥ 0 .5可视为异常 ,异常控制线为 5 % ,滑动窗长为 3,异常出现 1a左右 ,在其周围会有相应的地震发生 ;水位变差值ΔC>0 (m ) ,持续时间大于等于 12个月 ,可视为异常     

山西省地下水位干扰异常特征分析

以2010年以来山西10个水位测点的观测数据为基础,深入分析水位观测中非地震活动期间各类干扰因素,并根据干扰异常的成因归纳出典型的干扰异常图像.     

The Hydrological Regime and the Peculiarities of Formation of the Po River Delta

The peculiarities of the hydrological regime of the delta and near-shore zone of the Po River are discussed. The intrusion of salt seawater into the delta is described. The history of the Po Delta formation has been restored on the basis of the analysis of historical, archeological, and cartographic data. As shown, the peculiarities of hydrological and morphological processes in the Po River mouth are associated with natural and specifically with human-induced variations in sediment runoff of the river, with levee construction along branches, subsidence of deltaic deposits, and eustatic rise of the sea level.     

基于小波分析的水位观测气压效应研究

为研究水位气压效应的主要特征, 采用广西南宁石埠、 九塘两个台站的水位、 气压观测资料, 利用小波分析、 交叉小波分析、 小波相干分析方法在时间-频率空间内对二者的周期特征以及二者的相关特征进行了分析。 结果表明: 水位观测数据的显著周期为7.8~14.7 h, 气压观测数据的显著周期为7.8~14.7 h和17.5~27.8 h; 水位和气压存在7.8~14.7 h尺度的共振周期; 水位和气压在较宽的周期尺度上存在着显著的相关性, 且水位和气压的相关系数随周期和时间变化, 二者的相对相位角也因周期的不同而存在差异。     

东郭井水位与水温成组异常及其映震特征

分析了东郭井自2008年1月观测以来出现的水位与水温成组异常及其与周围中等地震活动的关系,研究结果显示:异常与地震有较好的对应关系,其异常的基本特征是水位阶降与水温缓升的形态配套,异常的幅度与震级大小有一定关系,异常持续的时间与井震距有一定的关系,还讨论了异常的机理。     

Regularities in the Formation of Coronal Mass Ejections Associated and not Associated with Type II Radio Bursts

Geomagnetism and Aeronomy - Regularities in the formation of coronal mass ejections (CMEs) associated (Radio Loud, RL CME) and not associated (Radio Quiet, RQ CME) with type II radio bursts (RBIIs)...     

山西大同-阳高6.1级5.8级地震阳高后贵仁水井水位异常动态

叙述了山西省大同—阳高 1 989年 1 0月 1 8日 6.1级和 1 991年 3月 2 6日 5.8级地震震前、震后山西省阳高县后贵仁水井水位的异常变化 ,在对水位异常和进行跟踪分析研究的基础上 ,得出阳高县后贵仁水井水位对 2次大同—阳高地震有较好异常反映的结论