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1.
近10年历史震例的分析表明,江苏苏05井、苏06井水温观测资料异常与江苏及邻省中等地震有很好的对应关系。本文对2010年后两口井的观测数据进行分析,总结了苏05井、苏06井水温测项在震前的典型异常特征:①异常表现为打破上升趋势的下降变化;②震前异常持续时间为2-3个月左右,映震范围在300km左右;③两口井的震前异常幅度在0.003℃左右。根据总结的异常特征并结合水温与井孔结构关系、水温与水位的关系、不同层位水温观测原理以及水化分析结果等,对异常可能的成因进行了初步探讨。  相似文献   

2.
We investigated the physical properties in the upper mantle beneath the Philippine Sea using a theoretical relation derived by Karato [Mapping water content in the upper mantle. Subduction factory, AGU Monograph, in press]. From the attenuation model of Shito and Shibutani [Phys. Earth Planet. Interact., in press] and the velocity model of Widiyantoro et al. [Earth Planet. Sci. Lett. 173 (1999) 91], observed attenuation and velocity anomalies were evaluated to explain the temperature, water content, and chemical heterogeneities in the target area. The results indicate that the observed anomalies in the shallower regions (50–200 km) may be due to chemical composition effects (e.g., concentration of iron), in addition to the temperature and water content anomalies. In contrast, for the deep upper mantle (300–400 km), the observations can be explained by only the effects of high water content (10–50 times higher than the average mantle). These inferred properties of the mantle are consistent with the tectonic history of the Philippine Sea region, which has had a long history of subduction and active magmatism.  相似文献   

3.
In liquefied ground, lateral flow is sometimes much larger than surface settlement and may exceed several meters even in a gentle slope of less than a few percent. It occurs not only during but also after earthquake shaking. Conventional laboratory soil tests using uniform sand cannot reproduce this phenomenon. Its mechanism is still poorly understood. In this paper, there is a major focus on the mechanism involving void redistribution or water film effects in layered sand deposits using recent findings obtained by different researchers on void redistribution and the associated lateral flow movement that potentially occurs in layered sand deposits. 1G shake table tests, 1D tube tests, torsional simple shear tests, in situ soil investigations, case history studies, etc. are used to develop an understanding of the lateral flow mechanism during liquefaction. Some of the major findings are; sand deposits in the field consist of sublayers with different particle sizes and permeability and readily develop water films by post-liquefaction void redistribution at sublayer boundaries. The water films may have served as sliding surfaces for large flow during the 1964 Niigata earthquake without the constraint of the dilatancy effect because the water films serve as shear stress isolators. The potential of this type of flow failure will be high for loose sand with relative density around 40% or less.  相似文献   

4.
Santos-São Vicente estuary, located in São Paulo State, Brazil, has a history of contamination by inorganic chemicals such as mercury (Hg). In the 1980s the Cubatão was considered one of the most polluted sites in the world as a consequence of the intense industrial activities located in the city close to the estuary. To provide data and evaluate the local biota, total mercury (THg) contents were determined in sediments and in fish, Cathorops spixii, from different areas of the Santos-São Vicente estuary. For comparison, samples were also collected in a non-polluted system with similar hydrochemistry characteristics, the Cananeia estuary. The water characteristics and THg levels in sediment and fish samples confirmed a high human influence in the Santos-São Vicente estuary. The lowest THg values, observed in Cananeia, were evidence of low anthropogenic influence. High values observed in Santos-São Vicente show the necessity for a monitoring program.  相似文献   

5.
Quality Requirements for Fresh Waters: Water Quality Targets, Water Quality Objectives, and Chemical Water Quality Classification In the Federal Republic of Germany, water quality requirements for the protection of inland surface waters against hazardous substances are formulated on the basis of a quality targets derivation concept developed jointly by the Federal Government and the Federal States. The quality requirements were termed “water quality targets” in order to make it clear that the values derived are orientational values rather than legally binding limit values. The international comparison of quality requirements for surface waters shows that, on the whole, the national quality targets ensure a high level of protection. According to present scientific knowledge, impairments of uses, such as supply of drinking water, or risks to aquatic communities need not to be expected if the quality targets are complied with. A comparison of water quality data with the water quality targets makes it possible, on the one hand, to identify those substances whose inputs must be further reduced; on the other hand, it also shows that, for a number of substances, there is no need at present for concern over their adversely water quality. A further differentiation of the aquatic hazard potential of pollutants allows a water quality classification system to be developed on the basis of the quality targets derivation concept. The basic elements of this water quality classification system are presented, and its application is explained by way of examples.  相似文献   

6.
Rainwater and reclaimed wastewater for sustainable urban water use   总被引:2,自引:0,他引:2  
Concern about the sustainability of urban water use is the strong motivation to understand the potential of rainwater use and water recycling in urbanized cities. The history of water supply in Tokyo and its experience may provide useful information to develop sustainable urban water use and find future possible tasks in rapidly growing cities. Besides, various innovative strategies to meet the current and future water demand in Tokyo may help us to consider new approaches adjusting to the developing mega cities in Asia. In this paper, the past and current practices on utilization of latent water resources such as rainwater and reclaimed wastewater in Tokyo are summarized from the viewpoint of sustainable water use.The storage of rainwater is a useful measure for water demand in emergency cases. In addition, the rainwater use can work as a kind of environmental education to make citizens aware of sustainable urban water use. There are 850 facilities for rainwater use in Tokyo. Since reclaimed wastewater use has several benefits, a huge water volume has been utilized for various purposes such as washing, water-cooling, toilet flushing, waterway restoration and creation of recreational waterfront. From the viewpoint of human health risk, new micropollutants such as estrogens, endocrine disrupters and surfactants should be considered as quality guideline parameter besides the conventional ones. Importance of infiltration facilities should be also highlighted to secure the sound water cycle. Groundwater recharge through the infiltration facilities provide a potential storage of water resource which can be withdrawn in the future if necessary.  相似文献   

7.
Quantification of water balance components, under arid conditions, is essential to the development of water management policies. This study demonstrates the application of the mass water balance approach for the assessment of water resources in a typical watershed located in the southwestern region of Saudi Arabia. The water balance approach was used, on an event basis, to express the amount of precipitation for 13 storms over a three year period, as a percentage of other hydrological components such as runoff, evaporation, and recharge. The study indicated that 63 per cent of precipitation is lost through evaporation from the water surface during flooding, and from the upper layers of the soil surface immediately after storms. Another 32 per cent is stored in the form of soil moisture in the unsaturated layers below the effective evaporation depth. Only 3 per cent of the precipitation was transformed into surface runoff; however, 75 per cent of this contributes towards groundwater recharge. This study has illustrated that the mass water balance approach can be used, with reasonable accuracy, to quantify the components of the hydrological processes under arid conditions, where a reliable data base is available. This, in turn, will help in the development of appropriate water management policies for arid regions.  相似文献   

8.
丰满台水氡,对远距离强震前兆异常显示,水氡井水位失稳状态,对应省内ML4左右地震对应率较高,本文从“古三论”(倍九论,节气论,穴位论)的角度讨论丰满水氡及水氡井水位异常,以便为综合预报,提供更多,信度更高的前兆信息。  相似文献   

9.
Water scarcity and stress have attracted increasing attention as water has become increasingly regarded as one of the most critical resources in the world’s sustainable development. The Water Poverty Index (WPI), an interdisciplinary but straightforward measure that considers water availability from both the bio-geophysical perspective and the socio-economic perspective of people’s capacity to access water, has been successfully applied at national, regional, and local levels around the world. However, the general assessment of water stress at a macro level over only a snapshot limits the understanding of the geographic differences in and dynamics of water stress; this will, in turn, mislead decision-makers and may result in improper water strategies being implemented. In addition, to date, the typologies and trajectories of water stress have been underexplored. To fill this knowledge gap, we examine the spatio-temporal patterns, trajectories, and typologies of water stress using an adapted WPI for six counties in Zhangye City, which lies within an arid region of China, in order to provide policy priorities for each county. The results of our assessment indicate that water stress has become more severe over time (2005–2011) in most of the counties in Zhangye City. The results also show a distinct spatial variation in water scarcity and stress. Specifically, the results for Shandan county reflect its progressive policies on water access and management, and this county is regarded as engaging in good water governance. In contrast, Ganzhou district has faced more severe water pressure and is regarded as practicing poor water governance. Typology results show that each county faces its own particular challenges and opportunities in the context of water scarcity and stress. In addition, the trajectory map reveals that none of the counties has shown substantial improvement in both water access and management, a finding that should draw decision-makers’ close attention.  相似文献   

10.
对河北辛集井进行了50~200m深度内的井水温梯度测试,结果表明测试深度内存在3处负梯度段(50~60m处、90~110m处、130~140m处)。在50~60m深度处的水温负梯度位置,发现了清晰的水温固体潮,其相位与水位固体潮相反。根据该井的综合钻井资料、水文地质条件分析认为水温负梯度可能与井管外低温含水层热交换有关,并讨论了负梯度处的水温固体潮特征。  相似文献   

11.
12.
昌黎井水氡、水位、降雨之间的相关分析   总被引:13,自引:0,他引:13  
张素欣  郑云贞 《地震》1999,19(3):309-312
对1982年至1997年昌黎井的水氡、水位月均值和昌黎气象站的降雨资料,以不同的时间尺度进行了相关计算。结果表明, 水氡与水位资料的趋势变化具有很好的相关性(R=0.833, n=168)和同步性。较小时间尺度的相关计算结果显示,水位、水氡与降雨不仅具有相关性、同步性,而且也具有差异性,这种差异性特征可作为地震前兆异常,并与唐山地区的地震对应较好,据此可作为短期地震预报指标。  相似文献   

13.
九江1井水位与水温对大震的同震响应特征及机理浅析   总被引:1,自引:0,他引:1  
统计分析九江1井2008—2011年水位、水温在多次大震中的同震响应特征,结果显示:水位通常表现为在正常背景下振荡,水温则通常表现为突降后恢复正常,水位和水温对远场大震的同震响应存在着一致性。同时,九江1井水位对地震的同震响应灵敏性优于同井水温观测,但水位观测受降雨影响,且气压效应明显。  相似文献   

14.
Chenghai Wang  Yipeng Guo 《水文研究》2012,26(10):1509-1516
In this article, the trends and variability of precipitation and precipitable water (PW) over the Qinghai‐Xizang (Tibet) Plateau (QXP) (1970–2009) were analysed by using ERA‐40 (The European Center for Medium‐Range Weather Forecasts (ECMWF) 40 years Re‐analysis) and NCEP (The National Centers for Environmental Prediction)/NCAR reanalyses data and the ground observed precipitation data from 60 sites. The results showed that the precipitation over the QXP had an overall increasing trend; however, a slight decreasing trend was observed over the southeast. This decreasing precipitation trend might be related to the South Asia monsoon degradation. Since 1970, a decreasing PW trend has occurred over the QXP in which the southeast is the most significant region. Because of the rising temperatures in the QXP, a remarkable PW conversion rate (PWCR) increase of 0.87% per decade has occurred over the past 40 years. Because of its steep terrain, the PWCR in the middle eastern region of the QXP increased faster than that of the other regions. The mean PWCR in the wet southern region of the QXP was higher than that of the dry northern region, which was higher in the winter than that in the summer. Although much precipitation occurred in the summer, in the wet regions, the PWCR was higher in the winter than in the summer. The PWCR peak in the wet and dry regions occurred during the precipitation‐short and precipitation‐sufficient seasons, respectively. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

15.
The state of Texas has implemented a modeling system for assessing the availability and reliability of water resources that consists of a generalized simulation model called the Water Rights Analysis Package (WRAP) and input datasets for the state's 23 river basins. Reservoir/river system management and water allocation practices are simulated using historical naturalized monthly streamflow sequences to represent basin hydrology. Institutional systems for allocating streamflow and reservoir storage resources among numerous water users are considered in detail in evaluating basinwide impacts of water management decisions. The generalized WRAP model is a flexible tool that may be applied to river basins anywhere. The Texas experience in implementing a statewide modeling system illustrates issues that are relevant to water management in many other regions of the world.  相似文献   

16.
Tidal phase of water temperature in Qixian well, Shanxi Province is ahead of water level, which is different from the normal tidal relationship between water temperature and water level. Observation curves of this phenomenon are introduced in this paper, and co-seismic response data of water temperature and water level are used to check the thermometer time system, confirming that this phenomenon is true. Using the harmonic analysis method, variations of time difference between water temperature and water level for the M2 wave are worked out, which indicates that this phenomenon exists during the whole observation. According to the variations of phase lags for water temperature and water level, and the survey of observation conditions, it is considered that the abnormal phenomenon may be related to inadequate passage of water caused by a well blockage at the depth where the water temperature probe was set.  相似文献   

17.
基于洱海水生态特征的流域最大日负荷总量控制   总被引:1,自引:1,他引:0  
基于洱海水生态历史数据及现状资料,采用概率密度分布曲线法及水生生物基准相结合的方式计算洱海总氮(TN)、总磷(TP)、高锰酸盐指数(COD_(Mn))和氨氮(NH_3-N)的控制目标,目标值分别为0.36、0.026、4和0.28 mg/L.再根据该水质目标,得到洱海的最大日负荷(TMDL)总量.TMDL总量采用线性规划法计算,其中污染物响应系数矩阵通过MIKE 21二维水质模型计算所得.安全容余(MOS)则通过一阶误差分析法确定.经过一系列的计算,最终确定洱海的TMDL总量控制计划.计算结果表明,洱海TN、TP、COD_(Mn)和NH_3-N的TMDL总量分别为2005.989、149.671、19258.844和1348.119 kg/d,其MOS所占比例分别为6.152%、5.570%、4.380%和5.021%,表明洱海农业面源污染为该流域主要的污染形式,其允许最大排放量约占全部允许排放量的90%左右.  相似文献   

18.
祁县井水温和水位的奇异潮汐关系探讨   总被引:1,自引:1,他引:0  
马玉川  王博 《中国地震》2014,30(1):55-63
山西祁县井水温潮汐相位超前于水位,异于正常的水温和水位潮汐的动态关系。本文介绍了此现象的记录图像,通过水温和水位同震响应数据核实仪器时间系统,证实此现象是客观的;利用调和分析方法计算出逐月水温与水位潮汐变化的时间差,表明此现象存在于整个观测中。根据水温和水位潮汐相位相关性分析及观测条件调查,认为祁县井水温潮汐相位超前于水位的现象是在特定观测条件下,因井水流动不畅引起的特殊的水温水位关系。  相似文献   

19.
Our study describes and evaluates environmental influences on assemblages of aquatic Coleoptera and Heteroptera in artificial ponds situated near Lake Steinhude in Lower Saxony (Germany). We determined temporal dynamics and colonization patterns for 14 ponds of different age. In total, we recorded 4941 individuals that represented 87 species of aquatic beetles and bugs. Between 30 and 40 species were found in most of the ponds. Heteropteran species of the families Corixidae and Notonectidae acted as pioneer species in new ponds, while aquatic coleopterans predominated in older ponds. The results of Canonical Correspondence Analyses (CCA) showed that among the key factors affecting community structure were land use, vegetation cover, water chemistry and the age of the ponds. We found that the distribution of adjacent ponds on areas with different land use has a positive influence on the diversity and abundance of the aquatic insect fauna.  相似文献   

20.
平凉C11井地下流体数字化观测资料的分析   总被引:1,自引:0,他引:1  
张昱  钟美娇  杨晓鹏  杨斐  史继平 《地震》2008,28(4):128-135
C11井是甘肃唯一一口数字和模拟观测同时并行的地下流体观测井, 2001年9月开始数字观测正式产出资料, 与模拟观测相比, 数字化观测数据信息量大, 传输速度快, 人为误差小。 该文分析了平凉C11井数字化水位、 气压、 水温等测项观测资料。 结果表明, 数字水位动态与模拟水位动态一致性较好、 数字水位与数字气压动态之间相关性较好, 数字水温与模拟水温的动态一致性不如水位好; 数字水位的潮汐效应非常明显, M2波潮汐因子相当稳定(平均值1.1538), 相对误差较小(平均值0.0215)。  相似文献   

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