Karstic Groundwater Origin and Recharge Process in Zagros Region: Insights From Stable Isotopes (δ18O and Δ2H) Approach

Zagros is an important region with high quality and quantity karstic water resources in the Middle East. This region provides a dominant part of potable and agricultural water needs for its inhabitants as well as agricultural water needs for nearby regions. Therefore, studying karstic water resources in Zagros by accurate methods such as stable isotopes techniques is very important. In this investigation, hydrological characteristics of groundwater resources including groundwater origin, recharge rate and recharge elevation have been studied using stable isotopes (18O and 2H). The results show that stable isotopes signatures in groundwater resources show notable variations across Zagros and groundwater resource mainly plot on south and west Zagros meteoric water lines. In addition, recharge elevation and recharge rate in groundwater resources also show significant variations in Zagros. Finally, the stable isotopes signatures in precipitation and groundwater has been used to study the role of each dominant air mass (contribution percentage of precipitation events originate from each air mass) in groundwater resources recharge using Simmr package in R language. Overall, groundwater resources in Zagros is recharged by precipitation events originate from various air masses and they have various recharge rates and recharge elevations.

Groundwater Origin and Quality Appraisal through a Combined Geochemical and Isotopic Approach in the Great Algiers District (Algeria)

The assessment of the origin of water that is allocated both for people and for irrigation in the eastern part of the Mitidja plain was carried out making use of geochemical and isotopic tools (18O, 2H and 3H). Both hydrochemical and isotopic information gathered for eastern Mitidja alluvial aquifer were used for the sake of assessing the mechanisms controlling groundwater chemistry. This allowed one to identify: (i) the natural or the anthropogenic processes that control groundwater quality, (ii) the origin of groundwater and when its recharge occurs. The work involved sampling campaigns, in situ measurements, and analyses of ions, heavy metals and water isotope content. Results showed a fair overall chemical quality of waters, since the assessment of water quality using water quality index (WQI) revealed that 90 % of the groundwater samples are good. Mitidja’s groundwaters fall into the Cl−SO4−Ca water type, that is mainly induced by water-rock interactions (dissolution of evaporites). The concentrations in Fe, Mn, Ni and Cd for some of the samples were found higher than the prescribed limits recommended by the World Health Organization. Isotopes indicate that groundwater is young since it originates from direct infiltration of precipitation that is mostly induced by Mediterranean atmospheric disturbances.

Integrated Hydrochemistry and Statistical Methods to Investigate Groundwater Origin and Salinization Process in Arid Regions (Central-eastern Tunisia)

Hydrochemistry is a discipline widely used given the groundwater quantitative and qualitative reliability in the hydrogeological study. The geochemical study of groundwater in the Nadhour-Sisseb-El Alem basin aimed to characterize the water chemistry, determination of the physicochemical parameters and chemical facies well as and the mineralization processes. The Piper and Durov diagrams and scatter plots, conventional classification techniques, are applied to evaluate the geochemical processes. Samples are classified using two multivariate statistical methods, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). Waters compositions are affected by cation exchange reactions in the intercalated clay, resulting in a Na+ increase, and peaks of K+, Ca2+ and Mg2+. PCA analyses show that the water samples have been classified into 8 groups. The waters quality deterioration is caused essentially by; overexploitation, decreased in freshwater recharge rates, climate condition; height evaporation low precipitation, artificial recharge by dam water, and irrigation return water.

Tracing groundwater circulation in a valuable mineral water basin with geochemical and isotopic tools: the case of FERRARELLE, Riardo basin, Southern Italy

The Riardo basin hosts groundwater exploited for the production of high quality, naturally sparkling, bottled water (e.g., Ferrarelle water), and circulating in a system constituted by highly fractured Mesozoic carbonates, overlain by more impervious volcanic rocks of the Roccamonfina complex. The two formations are locally in hydraulic connection and dislocated by deep-rooted faults. The study aimed at elucidating groundwater origin and circulation, using isotopic tracers (δ18O, δ2H, δ11B and 87Sr/86Sr) coupled to groundwater dating (Tritium, CFCs and SF6). Besides recharge by local precipitation over the Riardo hydrogeological basin, stable isotope ratios in water indicated an extra-basin recharge, likely from the elevated surrounding carbonate reliefs (e.g., Maggiore and Matese Mts.). The mineralization process, promoted by the deep CO2 flux, controls the B and Sr contents. However, their isotopic ratios did not allow discriminating between circulation in the volcanic and in the carbonate aquifers, as in the latter the isotopic composition differed from the original marine signature. Groundwater model ages ranged from ~ 30 years for the volcanic endmember to > 70 years for the deep, mineralized end-member, with longer circuits recharged at higher elevations. Overall, the results of this study were particularly relevant for mineral water exploitation. A recharge from outside the hydrogeological basin could be evidenced, especially for the more mineralized and valuable groundwater, and an active recent recharge was detected for the whole Riardo system. Both findings will contribute to the refinement of the hydrogeological model and water budget, and to a sustainable development of the resource.

Identifikasi Potensi Air Tanah untuk Kebutuhan Penyediaan Air Bersih dengan Metode Geolistrik: Studi Kasus di Kawasan Geostech, Puspiptek Serpong

ABSTRACTGeostech Building, as an office and laboratory facility, requires a source of clean water from groundwater related to the limited supply of clean water from the PDAM. Due to the needs of freshwater from groundwater origin, data and information are needed regarding the potential groundwater in the area, including aquifer configuration, depth, and groundwater potential. The presence of groundwater is not distributed through every area, and it's related to the geological and geohydrological conditions. One of the geophysical methods that can describe subsurface is 2D geoelectric methods. This method can distinguish and analyze rock types, geological structures, groundwater aquifers, and other important information based on the characteristics of the electricity of rocks by looking at the value of the type of resistance. In this measurement, the Wenner Alpha configuration has been used, where the arrangement of A-B current electrodes and M-N potential electrodes have constant spacing. From the measurement results, it can be interpreted that there is a low resistivity layer containing porous groundwater as an aquifer. Based on regional geological data, it has been estimated that this layer is in the form of sandy tuff (0-1.5 ohm-m). The exploitation of groundwater with drilling is expected to reach the aquifer's upper layer at depth, starting from 11.5-13 meters. The groundwater aquifer thickness cannot be ascertained because of the penetration of the lower depth of 2D geoelectric measurements truncated by the constraint of a maximum stretch of cable. The upper layer of the aquifer contains a turned layer of fine tufa and medium tuff, which is impermeable, coarse tuff, and mixed soil with varying thickness at the upper layer.Keywords: 2D geoelectric, aquifer, potential groundwater, Geostech ABSTRAKGedung Geostech sebagai sarana perkantoran dan laboratorium memerlukan sumber air bersih dari air tanah terkait dengan terbatasnya suplai air bersih dari PDAM. Kebutuhan air bersih berasal dari air tanah, maka diperlukan data dan informasi mengenai kondisi potensi air tanah di kawasan tersebut termasuk konfigurasi akuifer, kedalaman, dan potensi air tanahnya. Keberadaan air tanah tidaklah merata untuk setiap tempat dan sangat terkait dengan kondisi geologi dan geohidrologinya. Salah satu metode geofisika yang dapat memberikan gambaran kondisi bawah permukaan adalah dengan metode geolistrik 2D. Metode ini dapat membedakan dan menganalisis jenis batuan, struktur geologi, akuifer air tanah, dan informasi penting lainnya berdasarkan sifat kelistrikan batuan dengan melihat nilai tahanan jenisnya. Dalam pengukuran ini digunakan konfigurasi Wenner Alpha, dimana susunan elektroda arus A dan B dan elektroda potensial M dan N mempunyai spasi yang konstan. Dari hasil pengukuran dapat diinterpretasikan adanya lapisan dengan resistivitas rendah yang mengandung air tanah dan bersifat porous sebagai akuifer. Berdasarkan data geologi regional diperkirakan lapisan ini berupa tuf pasiran (0-1,5 ohm-m). Pengambilan air tanah dengan pemboran diperkirakan akan mengenai batas atas lapisan akuifer pada kedalaman 11,5-13 meter. Ketebalan akuifer air tanah tidak bisa dihitung karena penetrasi kedalaman pengukuran geolistrik 2D terbatasi oleh bentangan elektroda di permukaan. Lapisan di atas akuifer merupakan lapisan selang-seling tuf halus dan tuf sedang yang kedap air, tuf kasar, dan pada bagian paling atas merupakan tanah urugan dengan ketebalan bervariasi.Kata kunci: Geolistrik 2D, akuifer, potensi air tanah, Geostech

Teknologi Hidrotermal Sebagai Solusi Cepat Pengolahan Sampah Organik Menjadi Pupuk

ABSTRACTGeostech Building, as an office and laboratory facility, requires a source of clean water from groundwater related to the limited supply of clean water from the PDAM. Due to the needs of freshwater from groundwater origin, data and information are needed regarding the potential groundwater in the area, including aquifer configuration, depth, and groundwater potential. The presence of groundwater is not distributed through every area, and it's related to the geological and geohydrological conditions. One of the geophysical methods that can describe subsurface is 2D geoelectric methods. This method can distinguish and analyze rock types, geological structures, groundwater aquifers, and other important information based on the characteristics of the electricity of rocks by looking at the value of the type of resistance. In this measurement, the Wenner Alpha configuration has been used, where the arrangement of A-B current electrodes and M-N potential electrodes have constant spacing. From the measurement results, it can be interpreted that there is a low resistivity layer containing porous groundwater as an aquifer. Based on regional geological data, it has been estimated that this layer is in the form of sandy tuff (0-1.5 ohm-m). The exploitation of groundwater with drilling is expected to reach the aquifer's upper layer at depth, starting from 11.5-13 meters. The groundwater aquifer thickness cannot be ascertained because of the penetration of the lower depth of 2D geoelectric measurements truncated by the constraint of a maximum stretch of cable. The upper layer of the aquifer contains a turned layer of fine tufa and medium tuff, which is impermeable, coarse tuff, and mixed soil with varying thickness at the upper layer.Keywords: 2D geoelectric, aquifer, potential groundwater, Geostech ABSTRAKGedung Geostech sebagai sarana perkantoran dan laboratorium memerlukan sumber air bersih dari airtanah terkait dengan terbatasnya suplai air bersih dari PDAM. Kebutuhan air bersih berasal dari airtanah, maka diperlukan data dan informasi mengenai kondisi potensi airtanah di kawasan tersebut termasuk konfigurasi akuifer, kedalaman, dan potensi airtanahnya. Keberadaan airtanah tidaklah merata untuk setiap tempat dan sangat terkait dengan kondisi geologi dan geohidrologinya. Salah satu metode geofisika yang dapat memberikan gambaran kondisi bawah permukaan adalah dengan metode geolistrik 2D. Metode ini dapat membedakan dan menganalisis jenis batuan, struktur geologi, akuifer airtanah, dan informasi penting lainnya berdasarkan sifat kelistrikan batuan dengan melihat nilai tahanan jenisnya. Dalam pengukuran ini digunakan konfigurasi Wenner Alpha, dimana susunan elektroda arus A dan B dan elektroda potensial M dan N mempunyai spasi yang konstan. Dari hasil pengukuran dapat diinterpretasikan adanya lapisan dengan resistivitas rendah yang mengandung airtanah dan bersifat porous sebagai akuifer. Berdasarkan data geologi regional diperkirakan lapisan ini berupa tuf pasiran (0-1,5 ohm-m). Pengambilan airtanah dengan pemboran diperkirakan akan mengenai batas atas lapisan akuifer pada kedalaman 11,5-13 meter. Ketebalan akuifer airtanah tidak bisa dihitung karena penetrasi kedalaman pengukuran geolistrik 2D terbatasi oleh bentangan elektroda di permukaan. Lapisan di atas akuifer merupakan lapisan selang-seling tuf halus dan tuf sedang yang kedap air, tuf kasar, dan pada bagian paling atas merupakan tanah urugan dengan ketebalan bervariasi.Kata kunci: Geolistrik 2D, akuifer, potensi airtanah, Geostech

The hydrogeology of the transboundary Yarmouk Gorge: a case study

<p>The Lower Yarmouk Gorge (LYG) marks both hydrogeological and Geopolitical triple junction. It serves as a meeting point for groundwater flowing from the Syrian Haurn Plateau, the Jordanian Ajloun Mountain and the Israeli Golan Heights. It is also the natural outlet of the 6,833 km<sup>2</sup> transboundary Yarmouk drainage basin, which was one of the main tributaries of the Jordan River. Within the gorge, springs and boreholes exhibits various water types flowing in a wide range of temperatures. For the three riparian states, the uncertainty of groundwater origin and flow paths imposes difficulties on the management of water flowing towards the Gorge. In last few years a series of studies have attempted to unveil some of the mystery. Numerical representation of rainfall field is a method developed in order to cope with the lack of data and contributed to the assessment of water consumption and aquifer discharge at the ungauged/unreported upstream parts of the basin (Shentsis et al., 2018 and 2019). Hydrochemistry of groundwater has been investigated in light of the natural processes in the larger Yarmouk Basin and a methodology was devalued for identifying different groundwater bodies in multi-aquifer systems (Möller et al., 2016; Rosenthal et al., 2020). Finally, a new structural model for the transboundary Lower Yarmouk Gorge has been suggested based on data from Israel and Jordan (Inbar et al., 2019) and several numerical simulations have been conducted for the study of this enigmatic fractured hydrothermal system (Magri et al., 2015 and 2016; Gurezki et al., 2016). Finally, it seems that currently we are a few steps closer towards a better understanding of this complex transboundary system and the lessons learned here can be used in other transboundary system around the world.</p><p>Inbar, N., E. Rosenthal, F. Magri, M. Alraggad, P. Möller, A. Flexer, J. Guttman, and C. Siebert (2019), Faulting patterns in the Lower Yarmouk Gorge potentially influence groundwater flow paths</p><p>Magri, F., N. Inbar, C. Siebert, E. Rosenthal, J. Guttman, and P. Möller (2015), Transient simulations of large-scale hydrogeological processes causing temperature and salinity anomalies in the Tiberias Basin</p><p>Magri, F., S. Möller, N. Inbar, P. Möller, M. Raggad, T. Rödiger, E. Rosenthal, and C. Siebert (2016), 2D and 3D coexisting modes of thermal convection in fractured hydrothermal systems - Implications for transboundary flow in the Lower Yarmouk Gorge</p><p>Möller, P., E. Rosenthal, N. Inbar, and F. Magri (2016), Hydrochemical considerations for identifying water from basaltic aquifers: The Israeli experience</p><p>Rosenthal, E., P. Möller, I. Shentsis, C. Siebert, F. Magri, J. Guttman, and N. Inbar (2020), Natural Processes determining the hydrochemistry of the groundwater in the Yarmouk basin</p><p>Shentsis, I., N. Inbar, E. Rosenthal, and F. Magri (2018), Numerical representation of rainfall field in basins of the Upper Jordan River and of the Yarmouk River</p><p>Shentsis, I., N. Inbar, E. Rosenthal, and F. Magri (2019), Assessing water consumption and aquifer discharge through springs based on the joint use of rain and flow data in the Yarmouk River Basin</p>