Hydrological and hydrogeological characteristics of Wadi el Mujib catchment area,Jordan

Hydrological and hydrogeological data in the area have been verified to evaluate the availability and the potentiality of the water resources for the proposed damsites in the Wadi el Mujib catchment area, which is considered a semiarid to arid region. The quantity of the surface waters is very small compared with the surface area of the basin, however, due to the shortage of precipitation in the country and the necessity to attain socioeconomic objectives, the investigation of these waters has become more vital. The most reliable exploitation can be essentially achieved by constructing small storage dams on the suitable sites in order to benefit from the flood waters coming from the main wadis. For the above purpose, the hydrogeological and hydrological study of Wadi el Mujib catchment area was carried out, where the Wadi Mujib dam site will be constructed. The hydrogeological investigation of the groundwater was performed by constructing a groundwater contour map of the Amman-Wadi Es Sir aquifer (B2/A7) so as to verify the groundwater flow system and to determine the potentiality of the aquifer from the hydraulic parameters obtained from the pumping test analysis. The hydrological feasibility study of the dam was carried out by evaluating the water balance for a long-term period (1970 to 1990) in order to obtain reliable data that can be used to estimate the recharge to B2/A7 aquifer. In addition, a frequency analysis was performed to estimate the flood design of the reservoir area as well as the spillway at the proposed dam site.     

An integration of GIS and remote sensing in groundwater investigations: A case study in Burdur, Turkey

The importance of groundwater is growing based on an increasing need and decreasing spring discharges in the Burdur area. Remote Sensing and the Geographic Information System (GIS) have been used for investigation of springs, which are an important groundwater source. The chemical composition of groundwater is not of drinking water quality in Burdur city and water in the Burdur residential area is being obtained from the Cine plain.The purpose of this study was to investigate new water sources by using remote sensing and GIS methods. Geology, lineament and land use maps of the research area were prepared using the Landsat TM satellite image composed of different analyses on the TM 7–4-1 band. In addition, contours, creeks, roads and springs were digitized using a topographic map of 1/100,000 scale to produce a drainage density map. A groundwater potential map was produced which integrated thematic maps, such as annual rainfall, geology, lineament density, land use, topography, slope and drainage density. According to this investigation, the surrounding villages of Askeriye, Bugduz, Gelincik, Taskap and Kayaalt were determined to be important from the point of view of groundwater potential in the research area.     

The impact of hydrological changes on travertine deposits related to thermal springs in the Pamukkale area (SW Turkey)

Pamukkale thermal waters (35 °C), exhibiting calcium-bicarbonate-sulfate composition and high carbon dioxide concentration, are of a predominantly meteoric origin. The meteoric fluid, circulating through faults and fractures, is heated by magmatic intrusions at great depth, and ascends from deep reservoirs to the surface. Mixing with relatively cold groundwater in the near surface zone promotes different saturation conditions with respect to calcium carbonate that later precipitates at depth and/or the surface. Dissolution-deposition processes of calcium carbonate both at surface and depth environments may help to reconstruct past climate direction in the field. During wet climate conditions a high-rate of calcium carbonate accumulation would be expected to occur at the surface because thermal fluid would be under-saturated with respect to calcium carbonate at depth because of a relatively higher mixing ratio with cold groundwater. During dry climate conditions the thermal fluid would be super-saturated at depth because of the highly acidic environment. Hydrometeorological studies reveal that the annual precipitation at the Pamukkale hydrothermal field tends to decrease with time. This climatic change in the area was also detected from geological records. While humid climate conditions prevailed during the late Quaternary, the area has recently been affected by arid/semi-arid climate conditions, followed by some episodic transitions. This study has shown how the system has possibly reacted to different climate conditions since antiquity.     

Site selection for hazardous wastes: A case study from the GAP area, Turkey

The increase in the popularity of using environmental design criteria in town and country planning has brought about the need to fully identify the principles to determine the best location of hazardous wastes to be landfilled. This environmental management issue has received considerable attention because of its applications in urban and rural infrastructure planning, industrial development planning as well as health, housing, transportation and agricultural schemes. This paper explains a method to determine how to locate suitable sites for hazardous waste landfilling area by using the site screening study. It demonstrates how the criteria such as geology, topography, land use, climate, earthquake and other related factors can be introduced into the overlayer technique to determine the suitable site selection in a region. The research was undertaken in the Southeastern Anatolia Project (known as GAP in Turkey) region where identifying the land resources is crucial for agricultural and water management purposes. The paper also explains the validity of the method employed on the site selection process for hazardous wastes. The introduced method may enable more accurate design procedure for planning in environmental management in future.     

The Investigation of Mass Transfer in the Karasu Karstic Aquifer, Konya, Turkey

In this study, the changes in the chemical composition of the groundwater along a flow path were examined by using the water samples collected from unconfined, semi-confined and confined parts of the Karasu karstic aquifer. It was determined that transport of bicarbonate, calcium, and magnesium was dominant in unconfined and semi-confined parts of the aquifer, whereas calcite and dolomite precipitate in the confined parts. On the other hand, gypsum dissolution is present in all parts of the aquifer. In addition, the computed saturation indices explain the occurrences and precipitation of travertines in the Goksu Valley, which is the discharge area for the aquifer. Electronic Publication     

即墨市宝龙泉水文地质条件调查与分析

通过资料收集、专项地质测量、水文地质调查与测绘、水文地质物探、水文地质钻探、钻孔抽水试验、水质分析试验和综合研究等技术方法对宝龙泉区域水文地质条件进行了勘查,对泉的成因、汇水面积、补给量和流量进行了初步的分析和探索,结果显示:泉区内发育的7条近南北和近东西向的断裂异常构成了宝龙泉泉脉的构造格局,经钻探验证,3条断裂透水性好,含水丰富,其中DF1-3和DF3-4断裂为宝龙泉的主要泉脉通道;在水位标高53. 07 m时,泉水自流的流量为296. 76 m^3/d;泉水的矿化度为0. 582 g/L,水化学类型HCO3·SO4-Ca型。地下水水质主要类型分类为Ⅱ~Ⅲ类,均受不同程度的污染,主要适用于集中式生活饮用水水源及工、农业用水。按地表汇水面积和断裂形成的区域面积分别计算,可估算出宝龙泉流量平均为303. 78 m^3/d和337. 14 m^3/d。研究结果可为宝龙泉区域泉水的保护和开发利用提供依据。     

Hydrogeochemical and hydrogeological investigations of thermal waters in the Usak Area (Turkey)

Thermal waters of the Usak area have temperatures ranging from 33 to 63°C and different chemical compositions. These waters hosted by the Menderes Metamorphic rocks emerge along fault lineaments from two geothermal reservoirs in the area. The first reservoir consists of gneiss, schists, and marbles of the Menderes Metamorphic rocks. The recorded reservoir is Pliocene lacustrine limestone. Hydrogeochemical studies indicate that thermal waters were mixed with surface waters before and/or after heating at depth. The results of mineral equilibrium modeling indicate that all the thermal waters are undersaturated at discharge temperatures for gypsum, anhydrite, and magnesite minerals. Calcite, dolomite, aragonite, quartz, and chalcedony minerals are oversaturated in all of the thermal waters. Water from the reservoir temperatures of the Usak area can reach upto120°C. According to δ¹⁸O and δ²H values, all thermal and cold groundwater are of meteoric origin.     

Seismic risk assessment of buildings in urban areas: a case study for Denizli,Turkey

This study aims to carry out a seismic risk assessment for a typical mid-size city based on building inventory from a field study. Contributions were made to existing loss estimation methods for buildings. In particular, a procedure was introduced to estimate the seismic quality of buildings using a scoring scheme for the effective parameters in seismic behavior. Denizli, a typical mid-size city in Turkey, was used as a case study. The building inventory was conducted by trained observers in a selected region of Denizli that had the potential to be damaged from expected future earthquakes according to geological and geotechnical studies. Parameters that are known to have some effect on the seismic performance of the buildings during past earthquakes were collected during the inventory studies. The inventory includes data of about 3,466 buildings on 4,226 parcels. The evaluation of inventory data provided information about the distribution of building stock according to structural system, construction year, and vertical and plan irregularities. The inventory data and the proposed procedure were used to assess the building damage, and to determine casualty and shelter needs during the M6.3 and 7.0 scenario earthquakes, representing the most probable and maximum earthquakes in Denizli, respectively. The damage assessment and loss studies showed that significant casualties and economic losses can be expected in future earthquakes. Seismic risk assessment of reinforced concrete buildings also revealed the priorities among building groups. The vulnerability in decreasing order is: (1) buildings with 6 or more stories, (2) pre-1975 constructed buildings, and (3) buildings with 3–5 stories. The future studies for evaluating and reducing seismic risk for buildings should follow this priority order. All data of inventory, damage, and loss estimates were assembled in a Geographical Information System (GIS) database.     

Radiomagnetotelluric mapping, groundwater numerical modelling and 18-Oxygen isotopic data as combined tools to determine the hydrogeological system of a landslide prone area

Three methods were combined to determine the groundwater recharge and transfer processes of a landslide prone area. First, the radiomagnetotelluric method was used to investigate the distribution of electrical resistivity (ρ) of the subsurface and build a three-dimensional model of permeability (k), through an experimental relation between ρ and k. Second, this structural model of permeability and additional climatologic data were used to fix boundary and recharge conditions to perform a three-dimensional and transient numerical simulation of the groundwater flow. Finally 18-Oxygen time series observed at the main springs were used to validate the model. This association of methods led to an improved characterization of the groundwater flow system at local scale and a better understanding of the role of this system on the landslide phenomenon. This structured approach is thought to be useful to design specific remediation strategies to drain the unstable mass.     

Recognition of the hydrogeological potential using electrical sounding in the Khemisset-Tiflet region,Morocco

The low recharge of reservoirs and the increasing demand for water limit the potential of mobilized resources, especially in arid to semi-arid areas like Morocco. Integrated management is essential to safeguard this resource. In respect with this perspective, this work provides the analysis of hydrogeological potential of Khemisset-Tiflet region, which falls within the action area of the Sebou Hydraulic Basin Agency. The basis of our studies was as follows:(1) The interpretation of the existing geoelectric data;(2) application of geophysical methods for non-destructive reconnaissance and their integration into a Geographic Information System(GIS). The analysis demonstrates that: The map of the isohypses and the geoelectric cross-section of the substratum of the superficial roof aquifer show clearly a plunge associated with development of the Paleozoic roof in the South and the direction of flow of the surface water is from south to north, from the upper zone to the north of the El Kansera dam. These conclusions constitute very useful contribution for any resource management projects in this area.     

覆盖区智能地质填图的探索与实践——以森林沼泽区为例

截至目前,中国已经完成的1:5万区域地质填图工作主要分布于基岩裸露地区,很少涉及覆盖区。为了满足和适应新时代国家经济建设对地质调查工作的需求,未来中国地质填图工作必须向覆盖区推进。所以,利用机器学习与数据挖掘技术,按照地质填图的要求对海量多源异构地质数据融合与综合分析,是实现覆盖区智能化地质填图的关键环节。以浅覆盖森林沼泽区为例,充分利用航空磁测、土壤地球化学等结构化数据和遥感影像、地表地质等非结构化数据,开展聚类分析与人机交互深度学习2种算法模型的对比试验。结果表明,单一数据的聚类分析无法进行有效的地质单元划分,而利用多源数据进行人机交互深度学习和训练所获得的预测模型结果图件经检验与实际地质单元基本一致。本次试验,充分利用了机器学习功能和特殊算法,实现了计算机代替地质人员进行地质填图的探索,为森林沼泽区地质填图工作中设计地质图、工作部署和成果总结提供了示范案例,为覆盖区智能地质填图提供了借鉴。     

Groundwater quality in a coastal area: a case study from Andhra Pradesh, India

Over-exploitation of groundwater results in decline of water levels, leading to intrusion of salt water along the coastal region, which is a natural phenomenon. A groundwater quality survey has been carried out to assess such phenomena along the coast of Visakhapatnam, Andhra Pradesh, India. Brackish groundwaters are observed in most of the wells. The rest of the wells show a fresh water environment. The factors responsible for the brackish groundwater quality with respect to the influence of seawater are assessed, using the standard ionic ratios, such as Ca²⁺:Mg²⁺, TA:TH and Cl⁻:HCO⁻ ₃. Results suggest that the brackish nature in most of the groundwaters is not due to the seawater influence, but is caused by the hydrogeochemical process. Some influence of seawater on the groundwater quality is observed along the rock fractures. The combined effect of seawater and urban wastewaters is due to the inferior quality of groundwater in a few wells, where they are at topographic lows close to the coast.     

藏南泽当地区大反向逆冲断层变形研究——以磁组构与EBSD组构分析为例

仁布-泽当逆冲断层是喜马拉雅大反向逆冲断层（GCT）在藏南地区的重要延伸部分,也是喜马拉雅造山带北部边界新生代最为活动的构造单元之一。新生代以来特提斯喜马拉雅的构造变形组构特征的研究对于深入理解碰撞造山带演化与高原隆升具有重要构造意义。本文综合GCT泽当-琼结段断层的宏观与微观变形特征,对断裂带石英脉、围岩中石英和云母矿物的电子背散射（EBSD）组构及断层两侧岩石磁组构（AMS）特征进行对比分析。结果表明对AMS主要贡献来自顺磁性云母、绿泥石等,磁化率各向异性椭球体以压扁状为主,磁面理与构造面理（劈理、断层面）基本重合,显示较强的构造变形磁组构特征;磁线理优选方向近南北向,且与观测北向逆冲断层方向一致,揭示剪切作用在变形过程中的持续作用。研究发现泽当地区GCT附近石英微观结构从围岩至断层区,石英至少呈现3种不同类型的微观变形机制：围岩区溶解蠕变、断裂带石英以膨凸重结晶和亚颗粒旋转重结晶作用为主。断裂带石英的c轴EBSD组构指示变形为低温（300~400℃）环境,其中黑云母的结晶学优选（CPO）与磁组构主轴优选方向存在高度的一致性,进一步证实了顺磁性矿物黑云母对AMS的主要贡献。综合研究表明泽当地区GCT的韧性变形是断层处在中上地壳韧性带的活动阶段变形的结果,也代表了特提斯喜马拉雅在碰撞、高原隆升期的变形主要特征。

     

Groundwater quality degradation as a result of overpumping in the delta Wadi El-Arish area,Sinai Peninsula,Egypt

The delta Wadi El-Arish area of the Sinai Peninsula is one of the most important parts of Egypt for industrial and agricultural expansion projects because of its relatively abundant supply of groundwater. This study focuses on the hydrogeology and hydrochemistry of the Quaternary aquifer in the delta Wadi El-Arish area and on the impacts pumping has had on groundwater quality. The objectives were to determine the relationships between groundwater pumping and water levels and water quality, to estimate the hydraulic parameters of the Quaternary aquifer, and to determine the hydrochemistry of groundwater in the Quaternary aquifer and its suitability for irrigation. The conclusions are: (1) potentiometric surface elevations have declined by an average of about 0.5 m since 1981 in response to an increase in pumping, (2) the transmissivity of the lower Pleistocene calcareous sandstone (kurkar) unit is higher than the transmissivity of the upper Pleistocene alluvium, (3) groundwater in the Pleistocene aquifer is augmented with groundwater leaking from the overlying Holocene sand dune deposits through the intervening sandy clay aquitard, (4) groundwater in the kurkar is of lower quality than groundwater in the alluvium, (5) total dissolved solids (TDS) concentrations have increased by an average of about 1500 ppm since 1962, (6) an increase in saltwater intrusion has occurred in the northern part of the study area, and (7) the irrigation suitability of groundwater pumped from wells in much of the area is limited to salt tolerant crops. Our recommendations are: (1) no new pumping wells should be drilled and no increase in pumping rates should be allowed in the delta Wadi El-Arish area, (2) reliable estimates of the quantity of groundwater recharge should be made, (3) flood irrigation systems should be replaced by either drip or sprinkler     

The hydrological significance of cloud forests in the Sierra de las Minas Biosphere Reserve, Guatemala

This paper discusses the hydrological significance of socio-economic practices such as agricultural land use change and forest extraction to communities adjacent to the Sierra de las Minas Biosphere Reserve, Guatemala. Cloud forest hydrology differs from most environments because of the increased frequency of fog interception and fog precipitation. Fog precipitation occurs when intercepted cloud droplets coalesce on foliar and woody surfaces as fog filters through the canopy, and represents a significant proportion of the annual water inputs to cloud forests especially during the dry season. Interception data from this study showed that fog precipitation contributed greater than 7.4% of the hydrological inputs at 2550 m and less than 1% at 2100 m in the Sierra de las Minas. During the dry season fog precipitation contributed 19% of the hydrological inputs to the water budget of the cloud forest. Fog precipitation may be a significant hydrological input to the water resources of the local population. Socio-economic practices such as the conversion of cloud forest to agricultural land may decrease water resources for communities in Guatemala that demand greater quantities of water.     

中韩寒武系地层对比——以北京西山和韩国太白地区为例

韩国太白地区位于朝鲜半岛中东部,包含一套古生代地层,发育有下古生界寒武系地层,露头良好,易于观察。北京西山地区与韩国太白地区寒武系地层在岩性、沉积环境演化方面具有一定的可对比性。通过研究北京西山地区与韩国太白盆地上寒武统地层的岩性、沉积环境和古生物群特征,得出两者在构造演化之间的联系。     

Characterizing land displacement in complex hydrogeological and geological settings: a case study in the Beijing Plain,China

Characterization of land displacement induced by long-term overexploitation of groundwater is necessary to ensure sustainable water supply in Beijing, China. The northern part of the Beijing Plain is an important water source area and is also designed for groundwater recharge from South-to-North Water Diversion Project. We aim to depict the process of characterizing land displacement under complex hydrogeological and geological context in the region using remote sensing and geographic information system. Interferometric synthetic aperture radar time-series analysis was used to detect land displacement from 2003 to 2010. Statistic linear regression equations between groundwater level and land displacement were built based on linear consolidation principle. The spatial difference of Pearson correlation coefficient (R) and slope (k) were discriminated to quantify the response of land displacement to groundwater level change. The results show that there are two major displacement cones with annual rates up to ?40 and ?24 mm year^?1. R and k had a negative and positive correlation with increasing land displacement, respectively. A larger R reflects that the groundwater level has a closer relation with the occurrence of land displacement. The weak correlation is due to the delay in the propagation of the pressure drawdown in the fine-sediment layers or lens from the pumped aquifers where the pressure is measured. Thick compressible layer has more potential for land displacement. Results of this study are necessary to clarify the land displacement characteristics, to make full use of abundant spatial–temporal dataset, and ultimately to support hazard prevention and mitigation decisions.     

Environmental and hydrogeological problems in karstic terrains crossed by tunnels: a case study

The construction of one of the high-speed railway tunnels between Malaga and Córdoba (South Spain) beneath the Abdalajís mountains occasioned a series of hydrogeological problems with geotechnical and environmental impacts. The double tunnel, 7,300 m in length, runs south to north across several lines of small, calcareous mountains that have a highly complex structure. Beneath the Jurassic limestones lie Triassic clays and evaporites. Overlying the limestones is an essentially marly and limestone-marl Cretaceous series, which culminates with Miocene marls containing some organic matter. These mountains have generated springs that are used for urban water supply and irrigation, as well as drinking fountains in the surrounding villages. The initial water level in the aquifer series varied from 400 to 650 m above sea level. After drilling approximately 2,900 m, and intercepting a fracture zone within the carbonate rocks, a sudden water eruption occurred that reached a peak flow of 800 L/s. After a short while, spring discharges dried up, leading to a public protest. In this paper, we describe the geological and hydrogeological settings, the development of the aquifer as the drilling operation proceeded, the measures adopted and the responses subsequent to completion of the tunnel, including the effect of rainfall on the recovery of water levels. Lastly, a generalized estimate is made of how the system functions, and a forecast is made for recovery of its equilibrium.     

Neural networks and landslide susceptibility: a case study of the urban area of Potenza

For those working in the field of landslide prevention, the estimation of hazard levels and the consequent production of thematic maps are principal objectives. They are achieved through careful analytical studies of the characteristics of landslide prone areas, thus, providing useful information regarding possible future phenomena. Such maps represent a fundamental step in the drawing up of adequate measures of landslide hazard mitigation. However, for a complete estimation of landslide hazard, meant as the degree of probability that a landslide occurs in a given area, within a given space of time, detailed and uniformly distributed data regarding their incidence and causes are required. This information, while obtainable through laborious historical research, is usually partial, incomplete and uneven, and hence, unsatisfactory for zoning on a regional scale. In order to carry this out effectively, the utilization of spatial estimation of the relative levels of landslide hazard in the various areas was considered opportune. These areas were classified according to their levels of proneness to landslide activity without taking recurrence periods into account. Various techniques were developed in order to obtain upheaval numerical estimates. The method used in this study, which was applied in the area of Potenza, is based on techniques derived from artificial intelligence (Artificial Neural Network—ANN). This method requires the definition of appropriate thematic layers, which parameterize the area under study. These are recognized by means of specific analyses in a functional relationship to the event itself. The parameters adopted are: slope gradient, slope aspect, topographical index, topographical shape, elevation, land use and lithology.     

Hydro-morphological characteristics and hydrogeological functioning of a wetland system: a case study in southern Spain

The analysis and interpretation of physical and limnological parameters combined with hydrochemical (major ions and stable isotopes) analyses enabled us to evaluate the hydrogeological functioning and the hydrogeochemical evolution of groundwater in two adjacent lakes related to a karstic aquifer (Archidona, southern Spain). Lake water, groundwater and the outflow from a spring, were monitored periodically from 1998 to 1999 and sporadically from 2000 to 2006. The evolution of groundwater chemistry from recharge (dolines) to discharge areas (spring) showed an increment of 20% in magnesium and 15% in sulphate, and such higher increments were recorded for the water from the lakes, suggesting the existence of different hydrogeological paths. A simple water budget model, together with morphological interpretation, suggests that groundwater discharge into the lakes is of relative importance to the input into these systems. Finally, we believe that the development of a new typology for hydro-morphological elements, by means of several hydrological factors and the assessment of pressures and impacts will be useful for the correct management of these lakes and other semi-arid aquatic ecosystems.