September, 2025 || Volume 29 No.05
Volume 29(5) (2025)5-6
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1
Hydro-geophysical assessment of aquifer zones in Niger semi-arid regions
Rehmat Khan1 , Tanvi Arora1,2* , Sohelkhan Pathan1, 2, Ronak Dahiya2 and Rishu Pandey 1
1Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
2CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad 500 007, India
https://doi.org/10.71122/JIGU.29(5)2025.0029
ABSTRACT
Recognizing the critical role of groundwater as the primary drinking water source for millions worldwide, particularly in semi-arid regions like Niger, the UN Sustainable Development Goal (UN-SDG) aims to prioritize its sustainable management. Addressing water scarcity challenges through accessible, pure, and naturally filtered groundwater supports UN-SDG objectives for clean water and sanitation (Goal 6), ensuring its availability for domestic, agricultural, and industrial needs. This research contributes to the understanding groundwater potential zones and aquifer protective capacity in Niger's semi-arid region, supporting sustainable water resource management in Niger's semi-arid regions, Tillabery, Niamey, Dosso, Thoua, and Maradi. Using Vertical Electrical Sounding (VES) techniques, 166 data points were collected employing the Schlumberger electrode configuration. Geoelectric properties (resistivity and layer thickness) were derived, and Dar-Zarrouk parameters were calculated. Contoured maps visualizing longitudinal conductance (S), transverse resistance (T), and electrical a ed classify groundwater potential zones. The northeastern part showed low resistance, indicating a good groundwater potential zone. The aquifer is encountered at a depth of 11 m to 15 m in a sandy clay environment. Assessment of longitudinal conductance revealed a moderate to very good aquifer protective capacity, particularly in the southwestern and central-western sectors. To validate, eighteen borehole sites were analyzed, correlating findings with borehole drilling data to create a 3D aquifer thickness model. We found that the aquifer thickness is from 1.5 to 3.5 meters in certain regions exhibiting robust protective capacity, enhancing aquifer resilience against surface contamination. Analysis of the electrical anisotropy coefficient provided insights into geological structures like fractures and bedding planes, influencing fluid flow dynamics and contaminant movement.
2
Geomorphic study of the Late Quaternary-Holocene piedmont fans and fluvial terraces of Kota Dun, Kumaun Himalaya
Jonti Gogoi1,2,3, Prabha Pandey1,2, Anand K. Pandey1,2* and Devender Kumar1,2
1CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad- 500 007, India
2Academy of Scientific and Innovative Research (AcSIR) Ghaziabad- 201002, India
3RMIT University, 124 La Trobe St, Melbourne, Victoria 3000, Australia
https://doi.org/10.71122/JIGU.29(5)2025.0030
ABSTRACT
The Kota-Pawalgarh Dun is a Half-Dun structure shaped by spatial variation in active deformation partitioning within the Main Boundary Thrust (MBT)- Himalayan Frontal Thrust (HFT) wedge in the Central Kumaun Himalayan front. The post-Siwalik Piedmont fans consist of Dun gravels and provide a geomorphic and stratigraphic constraint on the deformation partitioning on the Dun. Though the fans were mapped, the lack of ages failed to constrain the definition of their stratigraphic and structural significance in the Late Quaternary evolution of the Dun. We present the new mapping results using field and remote sensing data with chronological constraints from the Optically Stimulated Luminescence (OSL) dating of river terraces and alluvial fans across the Dun valley. These new OSL ages of the fan and terrace sediments, in addition to published dates, reveal multiple phases of fan aggradation since > 90 ka until ~19 ka and incision during the Holocene with differential uplift, fan truncation, and fluvial reorganization, driven by ongoing tectonic activity. These findings offer valuable insight into the neotectonic development of the Kota Dun valley and contribute to a better understanding of the deformation processes in the mountain front in the Himalaya Central Seismic Gap region.
3
Geospatial assessment of groundwater quality and its suitability for drinking and irrigation in semi-arid regions of Andhra Pradesh (India) using water quality index approach
Ravi Kumar Pappaka1,, Srinivasa Gowd, Krupavathi Chintala, Pradeep Kumar
Dept. ofGeology, Yogi Vemana University, YSR, Kadpa,Ap
CSIR-National Geophysical Research Institute, Hyderabad
https://doi.org/10.71122/JIGU.29(5)2025.0031
ABSTRACT
Groundwater, a vital resource for drinking and irrigation in the semi-arid regions of Andhra Pradesh, is increasingly threatened by rapid depletion and quality deterioration due to growing demands from intensive agriculture and population expansion. In this study, a total of 92 groundwater samples were collected from boreholes during the pre-monsoon (PRM) and post-monsoon (POM) seasons, and their physicochemical properties were systematically analyzed. The major ion sequence in the groundwater was found to be Na+> Ca2+> Mg2+> K+ for cations, and HCO3 -> Cl-> SO4 2-> NO3 - > F- for anions. During the PRM season, only 19% of the samples met drinking water standards, with Water Quality Index (WQI) values ranging from 59.18 to 172.21. In the POM season, 22% of the samples were deemed safe for drinking, with WQI values ranging from 70.07 to 229.46. The majority of the samples were unsafe due to contamination from human activities, including improper sewage disposal and agricultural runoff. To assess the suitability of groundwater for agricultural and domestic use, Gibbs, USSL, and Wilcox diagrams were utilized. The Gibbs plot indicated that rock dominance governs the groundwater chemistry in the region. Most samples were highly suitable for irrigation, as evidenced by favorable Sodium Adsorption Ratio (SAR), %Na, Soluble Sodium Percentage prevalence of Ca2+-HCO3 - and Ca2+-Mg2+-Cl- water types. Using Geographic Information System (GIS) techniques, the spatial distribution of groundwater quality was mapped, showing that the majority of samples failed to meet drinking water quality standards, thus necessitating treatment before consumption. Groundwater with elevated concentrations of fluoride and nitrate is unsuitable for drinking purposes and should be avoided. The findings underscore the urgent need for sustainable aquifer management strategies to ensure the continued availability of safe groundwater for both domestic and agricultural use.
4
A geochemical study on the Lansdowne granite and granite gneiss, Garhwal Lesser Himalaya, Uttarakhand (India)
Deepa Arya1, Gunjan Arya1, 2, R.B. Ananth3
1Department of Geology, CAS, Kumaun University, Nainital, Uttarakhand-263001, India.
2Department of Geology, B.D. Govt. P.G. College Jaiharikhal, Pauri Garhwal, Uttarakhand- 246193, India.
3Department of Geology, Institute of Science, Banaras Hindu University, Varanasi- 221005, India
https://doi.org/10.71122/JIGU.29(5)2025.0032
ABSTRACT
The Lansdowne klippe in the Lesser Himalaya is a thrust-plunging syncline comprising Precambrian granite and granite gneiss, prominently exposed around Jaiharikhal-Lansdowne in Garhwal region. The study area consists metasedimentary rocks, quartzose-phyllite, mylonite/phyllonite, granitic and augen gneisses. Granites exhibit medium-coarse, hypidiomorphic, and porphyritic textures with minerals Pl-Kfs-Qtz-Bt-Mus-Tour-Mag-Ap-Zr-Ep. Granite gneisses exhibit a mineral composition similar to that of granite, but with a well-developed foliation plane. Near fault zones, mylonitic textures with quartz ribbons and sericite occurrences, indicate NW-SE shearing. Textural features (porphyritic, perthitic) and geochemical characteristics (alkalic-ferroan, peraluminous), suggest slow cooling from a direct magmatic origin within syn-collisional to post-orogenic settings.
5
Impact of triangular irregularity on the dispersion of SH-waves in a monoclinic crustal layer overlying a dry sandy medium
Tanishqa Shivaji Veer, A. Akilbasha and Vijay Kumar Kalyani*
Department of Mathematics and Statistics
Dr. Vishwanath Karad MIT World Peace University, Pune-411038, Maharashtra, India
ABSTRACT
In the present paper, a comprehensive study of dispersion characteristics of SH-waves in a monoclinic crustal layer lying over a dry-sandy half-space, with special emphasis on the effect of a triangular irregularity at the interface, has been conducted. We have considered both isotropic and monoclinic layer for the analysis of SH-wave propagation with or without sandiness in the half-space. The governing equations representing equation of motion of SH-waves in a monoclinic medium, is formulated to develop dispersion relation. Further, the results are analyzed and discussed for the variation in various physical parameters such as depth of triangular irregularity, sandiness and the directional dependencies in the monoclinic medium. Moreover, a comparative study has been conducted to assess the extent to which these parameters affect SH-wave propagation differently in monoclinic and isotropic layers. These results are illustrated graphically to highlight the importance of considering interfacial irregularity in seismic wave studies.