Large Springs Research Articles

Simple solutions for steady–state diffuse recharge evaluation in sloping homogeneous unconfined aquifers by means of atmospheric tracers

Environmental tracers of atmospheric origin are widely used to localise geographically recharge to aquifers and to quantify its average value. The most commonly used atmospheric tracers are chloride, water stable isotopes, tritium and radiocarbon. Their average input is spatially variable. Spring and pumped groundwater samples are often mixtures of water from a range of depths and thus their concentration in water may conspicuously differ from the tracer content in local recharge and even the recharge produced at the centroid of some up flow area. In the case of radiocarbon, most interpretation efforts are devoted to know the part of dissolved inorganic carbon originated from biogenic soil CO2 but seldom is considered that the water sample is often a mixture corresponding to a wide range of flow times along different paths in the unsaturated and saturated zones. Environmental tracer content in groundwater samples from large springs and long–screened pumped wells is interpreted and quantified. This is done under simplified idealised conditions, in homogeneous formations and under steady–state flow and mass transport through the unsaturated and saturated zones. Different input forms of the environmental tracer flow and mixing are considered, according with their specific characteristics, assuming linear variations with distance over the territory and three basic geometrical settings: parallel flow, radial divergent flow and radial convergent flow, besides a two-level geometry with homogeneous inputs. Tracer content in samples similar to those from a well-mixed reservoir differs from that of local recharge and depends on geographical position. The quantitative understanding of the slope effect, even if deduced from synthetic cases, improves recharge evaluation by means of chloride, shows how consider water isotopic distribution and altitudinal gradient in the aquifer, and demonstrates that radiocarbon ages may depend on position for a given geometrical shape of the aquifer, besides the large influence of the unsaturated zone thickness.

Archaeological Investigation Along the Route of U.S. 281, From Mulberry Avenue to Tuxedo Avenue in San Antonio

The route of impending U.S. 281 from Mulberry Avenue to Tuxedo Avenue in San Antonio traverses the valley of Olmos Creek. The creek originates in the southern edge of the Edwards Plateau between Leon Creek and Salado Creek, and flows in a southeasterly direction to its confluence with the San Antonio River. Near that confluence is a series of large fissure springs occurring along the fault zone. The topography of the drainage area varies from rolling to hill, with the area under concern in this report being undeveloped and covered with brush (Corp of Engineers, US Army, 1972).

A simple accurate chest-compression depth gauge using magnetic coils during cardiopulmonary resuscitation.

This paper describes a new method for calculating chest compression depth and a simple chest-compression gauge for validating the accuracy of the method. The chest-compression gauge has two plates incorporating two magnetic coils, a spring, and an accelerometer. The coils are located at both ends of the spring, and the accelerometer is set on the bottom plate. Waveforms obtained using the magnetic coils (hereafter, "magnetic waveforms"), which are proportional to compression-force waveforms and the acceleration waveforms were measured at the same time. The weight factor expressing the relationship between the second derivatives of the magnetic waveforms and the measured acceleration waveforms was calculated. An estimated-compression-displacement (depth) waveform was obtained by multiplying the weight factor and the magnetic waveforms. Displacements of two large springs (with similar spring constants) within a thorax and displacements of a cardiopulmonary resuscitation training manikin were measured using the gauge to validate the accuracy of the calculated waveform. A laser-displacement detection system was used to compare the real displacement waveform and the estimated waveform. Intraclass correlation coefficients (ICCs) between the real displacement using the laser system and the estimated displacement waveforms were calculated. The estimated displacement error of the compression depth was within 2 mm (<1 standard deviation). All ICCs (two springs and a manikin) were above 0.85 (0.99 in the case of one of the springs). The developed simple chest-compression gauge, based on a new calculation method, provides an accurate compression depth (estimation error < 2 mm).

Use of a flood-routing model to assess lateral flows in a karstic stream: implications to the hydrogeological functioning of the Grands Causses area (Tarn River, Southern France)

The aim of this study is to assess the spatio-temporal variability of lateral flows in the streams of a large karstic basin to construct a conceptual model of karst contributions to flood generation. The lateral flows of the Tarn River, which crosses the Grands Causses karst zone in Southern France, were investigated between several gauging stations along the river. First, through analysing the lateral flows on an event time scale of 30 floods, it was possible to identify the losing and gaining reaches, highlighting a highly variable attenuation/amplification role of karsts on flood generation. Second, the diffusive wave model was used to quantify the lateral flows on an hourly time step within a flood event. The simulations show a high variability of lateral outflows and inflows within a same reach according to the hydrometeorological conditions, with in some cases an inversion of the lateral flow direction during the flood. The results highlight complex surface/groundwater exchanges during a single flood event, with high river losses despite the concurrent flow of large springs feeding the stream. This spatio-temporal variability of the karst influence on flood generation was linked to the aquifer’s structure, which has improved the understanding of the hydro(geo)logical functioning of the Grands Causses massif. Finally, the new methodology proposed here opens challenging perspectives towards a framework for the analysis of surface–groundwater exchanges in karstic rivers.

Introductory editorial thematic issue: Mediterranean karst hydrogeology

This Special Thematic Issue of Environmental Earth Sciences (EES) is a collection of contributions from authors of the Mediterranean region in the specific field of karst hydrogeology. The editors invited well known researchers from Mediterranean countries, some of whom are members of the International Association of Hydrogeologists (IAH) Karst Commission, and encouraged them to provide a general or case history paper. Apologies are made to authors who were not invited with the hope to involve them in future projects. The idea to have such an issue originated during a meeting organised by the IAH-Italian Chapter in preparation for the 42nd Congress of IAH to be held in Rome in September 2015 (AQUA 2015). This opportunity is taken to thank the President of the Organising Committee of the IAH Congress, Marco Petitta, (University of Rome ‘‘La Sapienza’’) and Jo de Waele (University of Bologna) who have supported the idea and facilitated arrangements for this Special Thematic Issue. Support of the Editor in Chief of EES, James LaMoreaux, who approved the idea and followed up the publication process, is gratefully acknowledged. Thanks are also given to the Italian IAH Chapter, University of Rome ‘‘La Sapienza’’ and University of Sannio, which supported this issue. Finally, papers in this issue provide material that complements the Guides for several of the excursions organised on the occasion of this congress. Interest in karst aquifers continues to increase worldwide mainly because groundwater resources in these environments are generally more abundant than those in other environments which have been greatly exploited. In Mediterranean countries research in the field of karst hydrogeology has a long history and most methods have been applied and/or developed in various case studies in this region. The importance of karst aquifers in the Mediterranean area also relates to locally specific climatic conditions, characterised by long, dry and hot summers. Especially in the southern and eastern parts of the Mediterranean, the dry period could extend more than 6 months while in contrast the wet period could be reduced to 1–2 months. In such a climatic context variation of groundwater reserves in karst aquifers and the deficit of water in waterworks during dry periods (summer–autumn) is more the rule than the exception. Many engineering master works have been constructed in the past with the aim of regulating karst aquifer regimes; protecting fresh ground water from sea water intrusion; or keeping vulnerable karstic waters from uncontrolled pollution. These attempts have had great importance in the historical and economic development of the Mediterranean area as well as its civilization. The most powerful karst springs were easily tapped, and gravity channels allowed water to be supplied to high concentrations of people. Most large towns along the shoreline built up in the vicinity of large karstic springs. Ancient Rome and its empire are probably the most significant example: powerful karst springs fed ancient aqueducts, supplying large quantities of water for towns, villages, harbours, thermes and pools. More than 13 m/s of water flowed during that time & Francesco Fiorillo francescofiorillo@libero.it; francesco.fiorillo@unisannio.it

Study on the threshold of main factors restricting Jinan large karst springs spewing

Jinan spring groups are famous large karst springs in north China.The interaction of natural factors and human impact had caused a decline in jinan karstic water level.Jinan spring groups began to appear cutoff in 1972,and the cutoff lasted from1972 to 2002.To protect the jinan springs,some measures,like reducing groundwater exploitation and artificial recharge have been carried out.The result of regression analysis shows that,during that cutoff period,the main reason affecting spring water level is groundwater exploitation,but since 2003,Jinan spring groups have resumed spewing,and groundwater exploitation is no longer a major factor affecting the spring water level.Based on the series dynamic observation data of Jinan springs water level from2004 to 2012,it is determined that the development degree of Jinan karst is relatively high by the method of dynamic characteristics curve types of karst water level.Through SPSS software,the influence degree on springs water level caused by precipitation and artificial recharge was analyzed.The regression—autoregressive model was built,which shows that the last month precipitation has significant effect on the water level.Using the higher order trend mathematical model about springs water level and precipitation,it is calculated that the monthly precipitation threshold is 26.65~30.73 mm to maintain Jinan spring dynamic stability in dry season.Finally,for spring protection,the paper puts forward that the artificial recharge water quantity is not less than 165 600 m3/d in dry season.Research suggests that springs water level is sensitive to climate change and human activities,and our research results can provide some scientific basis for the jinan springs protection and groundwater recharge.

Characterization of the main karst aquifers of the Tezbent Plateau, Tebessa Region, Northeast of Algeria, based on hydrogeochemical and isotopic data

Chemical properties and hydrogeological characterization of water resources were studied in the Hammemt Plain, which is located in the northwest of the Tezbent mountain range, City of Tebessa, northeast of Algeria, which drains carbonate aquifers through various large karst springs. The physical and chemical characteristics of spring and well water samples were studied for 2 years in order to assess the origin of groundwater and determine the factors driving its geochemical composition. The ionic speciation and mineral dissolution/precipitation were calculated where we found that water wells, characterizing groundwater circulation at shallow depths, are moderate to highly mineralized waters of the Na-HCO3 type. In contrast to the shallow environment, the CO2-rich, deeper waters are of the Ca-HCO3 type, and undergo significant changes in their baseline chemistry along flow lines with increasing residence time. The main factors controlling the groundwater composition and its seasonal variations are geology, because of the presence of different carbonate formations, additionally elevation, and the rate of karst development. Supersaturation with respect to calcite indicates CO2 degasing occurs either inside the aquifer in open conduits or at the outlet in reservoirs. Undersaturation with respect to calcite shows the existence of fast flow and short residence-time conditions inside the aquifer. The main springs and wells of the Tazbent Mountain have been studied by means of stable isotope measurement, where the values are varied in 18O; between −8.2 and −7.76 for spring samples and from −8.26 to −7.15 for well samples and in 2H between −52.92 and −49.11 for spring samples and from −55.47 to −47.44 for well samples, showing that the groundwater recharge is of meteoric origin and suggests the absence of the evaporation effect on the isotopic composition.

Using groundwater age and hydrochemistry to understand sources and dynamics of nutrient contamination through the catchment into Lake Rotorua, New Zealand

Abstract. The water quality of Lake Rotorua has steadily declined over the past 50 years despite mitigation efforts over recent decades. Delayed response of the groundwater discharges to historic land-use intensification 50 years ago was the reason suggested by early tritium measurements, which indicated large transit times through the groundwater system. We use the isotopic and chemistry signature of the groundwater for detailed understanding of the origin, fate, flow pathways, lag times and future loads of contaminants. A unique set of high-quality tritium data over more than four decades, encompassing the time when the tritium spike from nuclear weapons testing moved through the groundwater system, allows us to determine detailed age distribution parameters of the water discharging into Lake Rotorua. The Rotorua volcanic groundwater system is complicated due to the highly complex geology that has evolved through volcanic activity. Vertical and steeply inclined geological contacts preclude a simple flow model. The extent of the Lake Rotorua groundwater catchment is difficult to establish due to the deep water table in large areas, combined with inhomogeneous groundwater flow patterns. Hierarchical cluster analysis of the water chemistry parameters provided evidence of the recharge source of the large springs near the lake shore, with discharge from the Mamaku ignimbrite through lake sediment layers. Groundwater chemistry and age data show clearly the source of nutrients that cause lake eutrophication, nitrate from agricultural activities and phosphate from geologic sources. With a naturally high phosphate load reaching the lake continuously via all streams, the only effective way to limit algae blooms and improve lake water quality in such environments is by limiting the nitrate load. The groundwater in the Rotorua catchment, once it has passed through the soil zone, shows no further decrease in dissolved oxygen, indicating an absence of bioavailable electron donors along flow paths that could facilitate microbial denitrification reactions. Nitrate from land-use activities that leaches out of the root zone of agricultural land into the deeper part of the groundwater system must be expected to travel with the groundwater to the lake. The old age and the highly mixed nature of the water discharges imply a very slow and lagged response of the streams and the lake to anthropogenic contaminants in the catchment, such as nitrate. Using the age distribution as deduced from tritium time series data measured in the stream discharges into the lake allows prediction of future nutrient loads from historic land-use activities 50 years ago. For Hamurana Stream, the largest stream to Lake Rotorua, it takes more than a hundred years for the groundwater-dominated stream discharge to adjust to changes in land-use activities. About half of the currently discharging water is still pristine old water, and after this old water is completely displaced by water affected by land use, the nitrogen load of Hamurana Stream will approximately double. These timescales apply to activities that cause contamination, but also to remediation action.

Karstification depth and storativity as main factors of karst aquifer regimes: some examples from southern Alpine branches (SE Europe and Middle East)

Karstic aquifers are the main groundwater source in Southeastern Europe and the Middle East. Many large springs and sources which drain Alpine orogenic belt and its branches are tapped and utilized for drinking water supply. Due to the unstable regime of the karstic springs, the main challenge for most of the waterworks is to ensure water supply during recession periods which coincide with the dry season, usually summer and early autumn months. Besides the problem of water shortage, water pollution of this open and generally very permeable type of aquifer is another major constraint in local water management. However, in comparison with other type of aquifers, the highly developed karst and its significant storage capacity as found in the studied areas may attenuate significant rainfall/runoff variations and possible climate changes. Most commonly, intensive rain episodes do not result in extreme floods in the studied karst terrains, while stored groundwater provides sufficient base flows for dependent ecosystems during the recession or periods of drought. Several typical hydrographs and results of some models applied for forecasting climate change impact presented in this paper represent a good example of specific karst aquifer behaviours and importance of considerable storage capacity in deeper parts of the aquifer.

Groundwater Flow Cycling Between a Submarine Spring and an Inland Fresh Water Spring

Spring Creek Springs and Wakulla Springs are large first magnitude springs that derive water from the Upper Floridan Aquifer. The submarine Spring Creek Springs are located in a marine estuary and Wakulla Springs are located 18 km inland. Wakulla Springs has had a consistent increase in flow from the 1930s to the present. This increase is probably due to the rising sea level, which puts additional pressure head on the submarine Spring Creek Springs, reducing its fresh water flow and increasing flows in Wakulla Springs. To improve understanding of the complex relations between these springs, flow and salinity data were collected from June 25, 2007 to June 30, 2010. The flow in Spring Creek Springs was most sensitive to rainfall and salt water intrusion, and the flow in Wakulla Springs was most sensitive to rainfall and the flow in Spring Creek Springs. Flows from the springs were found to be connected, and composed of three repeating phases in a karst spring flow cycle: Phase 1 occurred during low rainfall periods and was characterized by salt water backflow into the Spring Creek Springs caves. The higher density salt water blocked fresh water flow and resulted in a higher equivalent fresh water head in Spring Creek Springs than in Wakulla Springs. The blocked fresh water was diverted to Wakulla Springs, approximately doubling its flow. Phase 2 occurred when heavy rainfall resulted in temporarily high creek flows to nearby sinkholes that purged the salt water from the Spring Creek Springs caves. Phase 3 occurred after streams returned to base flow. The Spring Creek Springs caves retained a lower equivalent fresh water head than Wakulla Springs, causing them to flow large amounts of fresh water while Wakulla Springs flow was reduced by about half.

3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia

Beljanica Mountain in eastern Serbia is a part of the Carpathian Balkan arch (northern Alpine branch). It covers an area of about 300 km2 and consists mostly of Jurassic and Cretaceous limestones. Numerous surface karst features, long caves and several large karstic springs located in Beljanica’s piedmont along the contact of karstic and non-karstic rocks are all indicators of an intense karstification. Currently, the large karstic water reserves of Beljanica Mountain are not properly utilized because of their distance from main consumers, the objection by national water managers that the springs lack a stable and sufficient discharge particularly during recession periods. Due to its unpolluted and high quality water, the area is a great prospect for future water supply, and provides an opportunity for artificial regulation and for the design and implementation of specific tapping structures. This paper includes an analysis of the created 3D ArcGIS model of karst interior and its correlation with historical and newly collected data of spring discharges and groundwater physico-chemical characteristics. The results of karst aquifer monitoring (both quantitative and qualitative) are linked with the results of extensive field geological and speleological survey of the upper non-saturated part of the karst (such as sinkholes, pits and caves) and with the investigation of the permanently saturated deeper part of the aquifer (including the diving methods). The model of karst interior is based on the data from the 69 caves, 15 sinks and 1,682 dolines (sinkholes) surveyed. The total length of the karst channels network, calculated using the GIS model and presented in a 3D environment, is 647 km. The catchment areas of five major springs that drain the areas are estimated to range from only 7 km2 (Malo Vrelo Spring) to 124 km2 (Vrelo Mlave Spring). The groundwater exploitable reserves of Beljanica karst aquifer are estimated to be over 4 m3/s. The waters are low mineralized, unpolluted and have a great potential for water supply.

Differentiating between gravitational and tectonic faults by means of geomorphological mapping, trenching and geophysical surveys. The case of the Zenzano Fault (Iberian Chain, N Spain)

The Zenzano Fault scarp has been developed on the top of a 475m-high erosional escarpment underlain by an upper brittle sequence and a lower halite-bearing evaporitic formation. The 1850m-long fault, with a maximum displacement of 45m and parallel to the escarpment, has offset the back of a dip slope, generating an antislope scarp with prominent triangular facets up to 38m high and obstructing consequent transverse drainages (defeated streams). Both gravitational and tectonic interpretations were previously proposed for this active surface rupture. The fault scarp has been investigated by detailed geological and geomorphological mapping, geophysical surveys (GPR and ERT) and two trenches excavated across the fault in disrupted drainages. The geophysical profiles clearly imaged the fault, helping to site the trenches and roughly estimate the thickness of the deposits accumulated in the downthrown block. Although the maximum displacement to length ratio (Dmax/L) of the fault fall within the range of tectonic faults of similar length, according to the world database, the geological and geomorphological context, together with several parameters reveal that this structure corresponds to a gravitational failure: (1) anomalously high vertical displacement per event (>1.4m); (2) high apparent vertical slip rate (~0.6mm/year); and (3) short recurrence interval of faulting events. The negligible horizontal displacement component on the dip-slip fault, as well as the presence of very large caprock collapse sinkholes and saline springs, strongly suggest that interstratal karstification of the halite-bearing evaporites has played a primary role in the development of the gravitational failure. The formation of this morphostructure has been favoured by pre-existing tectonic faults, erosional unloading related to the removal of an overburden ca. 800m thick, and enhanced groundwater recharge due to the blockage of the drainage. This work illustrates that the proposed multidisciplinary approach allows the identification of features and calculation of parameters that may help to elucidate whether an active failure has a gravitational or a tectonic origin.

Hydrogeological mapping of the highly anthropogenically influenced Peligna Valley intramontane basin (Central Italy)

This paper presents hydrogeological mapping of the Peligna Valley (Central Italy) intramontane basin. The basin is hydrogeologically complex due to the significant surface and underground water resources which are extensively used for potable, industrial, agricultural and healing purposes. The basin history is characterised by significant fluvio-lacustrine deposition whose thickness can reach as much as 500 m. The depositional environment is completely surrounded by calcareous mountains. These represent extensive aquifers which feed large regional point and linear springs with total discharges of 16 m3/s. The highly complex hydrogeology of the study area and the varied use of water resources required extensive data collation and geological and hydrogeological assessments. Two years worth of hydrodynamic and hydrochemical monitoring of wells, springs, rivers and particularly artificial channels that convey water for industrial, hydroelectric and irrigational purposes were also undertaken. The construction of an accurate spatial-temporal database allowed the assessment and mapping of complex relationships between superficial water and groundwater. These relationships are shown in the 1:25,000 scale map. The map has been compiled using a detailed descriptive legend, various hydrogeological sections, schematics of anthropogenic activities, diagrams and tables and, finally, four schematics at 1:150,000 scale showing risk of contamination. It is hoped that this layout will assist in reading the map independently from any other supporting material.

Curved large tape springs for an ultra-thin shell deployable reflector

This article presents a study of large tape springs to be used as ribs of an ultra-thin shell space deployable reflector. The tape spring, both longitudinally and transversely curved, is made of carbon/epoxy composite and subject to two-dimensional or three-dimensional folds. The behaviour of tape springs with different dimensional parameters during folding is investigated by finite element analyses and an analytical approach. Peak moments, steady-state moments and strain levels are obtained for several parameters such as curvatures, length, thickness, subtended angle, etc. The analytical approach considers the bending strain energy during two-dimensional folding of the tape spring, and it does not capture the full behaviour due to the assumptions made for the simple solution. The results obtained by the two methods are compared where they are applicable and are in agreement for the tape springs subject to two-dimensional folds. Feasibility of the curved large tape springs as a rib-reinforcing element for the deployable reflector with 6 m diameter is investigated. A breadboard model of 90 cm diameter is manufactured and tested for packaging and deployment behaviour.

Regional groundwater flow and interactions with deep fluids in western Apennine: the case of Narni‐Amelia chain (Central Italy)

AbstractThe elemental fluxes and heat flow associated with large aquifer systems can be significant both at local and at regional scales. In fact, large amounts of heat transported by regional groundwater flow can affect the subsurface thermal regime, and the amount of matter discharged towards the surface by large spring systems can be significant relative to the elemental fluxes of surface waters. The Narni‐Amelia regional aquifer system (Central Italy) discharges more than 13 m3 sec−1 of groundwater characterised by a slight thermal anomaly, high salinity and high pCO2. During circulation in the regional aquifer, groundwater reacts with the host rocks (dolostones, limestones and evaporites) and mixes with deep CO2‐rich fluids of mantle origin. These processes transfer large amounts of dissolved substances, in particular carbon dioxide, and a considerable amount of heat towards the surface. Because practically all the water circulating in the Narni‐Amelia system is discharged by few large springs (Stifone‐Montoro), the mass and energy balance of these springs can give a good estimation of the mass and heat transported from the entire system towards the surface. By means of a detailed mass and balance of the aquifer and considering the soil CO2 fluxes measured from the main gas emission of the region, we computed a total CO2 discharge of about 7.8 × 109 mol a−1 for the whole Narni‐Amelia system. Finally, considering the enthalpy difference between infiltrating water and water discharged by the springs, we computed an advective heat transfer related to groundwater flow of 410 ± 50 MW.

A new approach in assessing recharge of highly karstified terrains–Montenegro case studies

The recharge of a karst aquifer, in terms of its quantity and spatial distribution, depends on various natural factors such as climate, topography, vegetation, soil, and geology. Selection of an adequate method for assessing recharge in karst is often a matter of dispute. Multi-parameter methods using Geographical information systems tools have recently been successfully developed and applied in karstic terrains of Spain and Lebanon. Specific local conditions such as highly karstified terrains could additionally complicate such an assessment. The Montenegro karstified terrains in the southern part of the External Dinarides are characterized by a very high precipitation rate, irregular seasonal distribution, and absence of surface waters (extremely high infiltration capacity of karst). Considering such conditions, an attempt to apply existing knowledge and experiences to the development of an appropriate multi-parameter method for assessing spatial distribution of autogenous recharge has been made. The KARSTLOP method has been developed, applied, and calibrated at catchments of several large karst springs of Montenegro. Obtained results in tested catchment areas confirm that with some further improvements the KARSTLOP method could be a useful tool to support research of karstic aquifers in similar highly karstified terrains.

Rainfall, spring discharge and past human occupancy in the Eastern Mediterranean

In ancient times human activities were tightly related and sensitive to rainfall amounts and seasonal distribution. East Mediterranean settlements were concentrated around numerous small to large springs, such as the Judean Mountains area. The goals of this study were to determine (a) the sensitivity of total discharge, recession curve, and response time of such springs to annual precipitation patterns, and (b) how spring hydrology responds to series of drought or wet years and to transitions from drought to normal and/or wet episodes (and vice versa). These goals were achieved by setting a finite-element hydro-geological flow model for selected perched springs that characterize the numerous springs throughout the carbonate karst terrain in the Judean Mountains. In addition, we estimated the effect of proposed regional past climate changes on the springs; in so doing, we transfer climate change to community size, livelihood and economic strength that were highly dependent on agricultural productivity. The results of the hydro-geological model revealed that these mountainous communities had the potential to prosper during historically wetter episodes and were probably adapted to short-term variability in annual rainfall. However, moderate to extreme droughts lasting only a few years could have led to a partial or even total abandonment of the springs as focal sites of intensive agricultural production. Spring drying eliminated the primary cause for the location of settlement. This occurred simultaneously in numerous settlements around the mountains of the southern Levant and therefore, must have caused dramatic economic and societal changes in the entire region, perhaps even resonating afar.

Water composition and minerals equilibria at the Syri i Kalter spring and in the Bistrica river (South Albania)

Syri i Kalter (“Blue Eye” in english) is the name of the largest spring of Albania, situated in the south of the country, not far from the town of Sarande. The spring is located near the tectonic contact between the Mesozoic-Paleogenic Mali i Gjiere carbonate sequence and the Terziary flysch units of the “Ionian Zone” of Albania. The discharge area is characterized by the presence of Triassic evaporites, mainly constituted by gypsum and anhydrite, associated with clay, limestones, dolomite and halite. The spring consists of several discharge points, yielding as a whole an average water flow of about 11 m3/s.

Effects of crystalline massif tectonics on groundwater origin and catchment size of a large spring area in Zieleniec, Sudety Mountains, southwestern Poland

The recharge mechanism of a very large spring area in the town of Zieleniec in the Orlickie Mountains (part of the Sudety mountain chain) in southwestern Poland, was investigated and characterized. The spring area is located on a steep mountain slope at a high elevation, next to the continental water divide. It is estimated that at least 90% of the spring discharge comes from outside its topographic drainage basin. The study area has been strongly affected by tectonic episodes of different ages. Thus, there is a high density of fractures in the crystalline massif, which determines the water content of the area and the occurrence of large springs. The low variability in discharge of the Zieleniec spring area indicates the presence of a strong and stable component source of recharge. It has also been shown that gravitational drainage of solid-rock blocks and small fissures is also an important recharge component. The stable recharge component is associated with deep-water circulation from the Bĕla River drainage basin in the Czech Republic, flowing beneath the continental divide. Water flows in conformity with a high hydraulic head gradient through deep, open, NW–SE-oriented fissures.

A hydrochemical and dye- tracing investigation in the Posht-e-Naz Karstic Aquifer, Alburz Mountain, Northern Iran

A hydrochemical and tracer study (uranine injection) was conducted in Jurassic limestone of the Posht-e-Naz area in the Alborz belt to evaluate hydraulic relations between a large diameter (about 100 m) sinkhole and springs and aquifer parameters. A main goal of the project was to find out the source of turbidity of the Emarate drinking water supply spring (SP4) in rainy season. Springs discharge were measured and hydrochemical investigation were carried out. The uranine tracer was injected and eight springs, three wells and the Neka River were selected and totally 989 samples in 107 days were collected. Hydrochemical data demonstrated a relative connection between sinkhole (Sh1) and spring (SP4). The results of the tracing by sampling water indicated only a hydraulic connection between Sange- Nou spring (SP8) and injection point, while the charcoal packets analysis revealed tracer exits from spring numbers SP1, SP3, SP4, SP5, SP8, in wells W1 and W2, and in the Neka River. The concentration — time curves of charcoal packets for qualitative analysis and exit tracer for quantitative analysis is also assessed.