The Tipan River, a tributary of Son River in Madhya Pradesh, India, is characterized by diverse geomorphic features such as pediment-pediplain complexes, low to moderately dissected hills, and an intricate river network. The soil of region ranges from clayey to loamy, underlain by geological formations including basalt, granite gneiss, limestone, and fine-grained sandstone. To address urgent need for sustainable groundwater management, this study integrates the Analytical Hierarchy Process (AHP) with Geographic Information System (GIS) tools to delineate groundwater potential zones (GWPZs). Eight hydrological parameters - rainfall, geology, geomorphology, soil, land use/land cover (LULC), slope, drainage density, and lineament density—were selected based on their relevance to groundwater occurrence and recharge. These were weighted through AHP using Saaty's 1–9 scale, with consistency verified (CI = 0.055, CR = 0.039). A weighted overlay analysis in ArcGIS Pro produced a GWPZ map, classifying basin into four classes: Poor (3.58%), Moderate (20.62%), Good (47.59%), and Very Good (28.21%). High groundwater potential was found in areas with gentle slopes, loamy soils, pediment-pediplain features, and high rainfall. The map's accuracy was validated using Receiver Operating Characteristic (ROC). Area Under Curve (AUC) value of 0.789, indicates strong predictive performance. Sensitivity analysis through the map removal method highlighted geology, geomorphology, and soil as the most influential parameters, while LULC showed minimal impact. This AHP-GIS approach offers a robust and replicable framework for groundwater assessment, supporting sustainable water resource planning in Tipan River Basin. Keywords: Tipan River Basin, Analytical Hierarchy Process, Geographic Information System, Groundwater Potential Zones, Sensitivity Analysis

Groundwater is absolutely vital for sustaining over 80% of agricultural irrigation in India, underscoring its critical importance in food production. However, ensuring groundwater sustainability remains a pressing challenge, particularly in regions with hard rock, such as the Deccan basalts. Formed millions of years ago through volcanic eruptions, this terrain is characterized by complex geological formations with variable basaltic layer thicknesses, classified into two types: 'simple' and 'compound'. Effective groundwater management in such settings requires integrated hydrogeological studies that rely on rainfall patterns, geological structures, and hydrographic data. To address these challenges, innovative approaches, such as BoreCharger, have been introduced. BoreCharger technology involves detailed hydrogeological investigations and perforation of borewell casings to enable recharge of deeper aquifers with freshwater from unconfined aquifers. This process enhances groundwater availability, improves quality, and revitalizes low-yielding or failing borewells, paving the way for sustainable water management. The present study, conducted at Khalad, Purandar, Maharashtra, demonstrates the positive outcomes of the BoreCharger application. Results show that BoreCharger-equipped borewells consistently sustain water levels until late March, ensuring a reliable supply for both agriculture and drinking purposes. Water quality has also shown significant improvement, with no adverse effects observed on groundwater levels or in nearby wells and water bodies. BoreCharger emerges as a powerful solution to combat the challenge of groundwater sustainability in basaltic terrains. Its ability to enhance both quantity and quality of groundwater highlights its potential for wider application beyond the study area. Keywords: Artificial Recharge, BoreCharger, Impact, Water Level, Khalad Area, Pune District

Groundwater resources within river basins are gaining global attention due to their critical role in sustaining human and agricultural needs. Preserving groundwater quality is essential for agricultural productivity and public health, as it serves as the primary source of drinking and irrigation water for billions of people worldwide. This study focuses on the hydrochemical characterisation and quality evaluation of groundwater in the lower urbanized regions of the Kallada River Basin (LKRB), covering Kollam town and its surrounding areas. This study aimed to assess water quality for drinking and irrigation purposes while also evaluating the underlying hydrogeochemical processes. The major cations and anions in groundwater follow the order: Ca2+ > Na+ > Mg2+ > K+ and HCO - > Cl- > SO 2-. The dominant groundwater type is Ca-HCO , followed by Na-Cl. The Water Quality Index (WQI) was employed to evaluate groundwater suitability for drinking. WQI analysis revealed that 80% of samples fell within the 'good to excellent' range, indicating suitability for drinking and domestic use, while 20% were classified as poor quality. Several indices, such as the Magnesium Hazard (MH), Sodium Adsorption Ratio (SAR), Residual Sodium Carbonate (RSC), Sodium Percentage (Na%), and Kelley's Ratio (KR), were used to assess the suitability of groundwater for irrigation. The findings indicate that although most samples are safe for irrigation, a few areas have problems with their water quality that render them harmful. This study helps with the sustainable management of groundwater resources in the LKRB by providing important insights for policymakers and urban planners. Keywords: Groundwater Chemistry, Hydro-chemical Facies, Drinking Suitability, Irrigation Suitability, Water Quality Index, Lower Kallada River

The seasonal variations in the textural parameters of beach sediments were studied along the Purangad-Gaonkhadi Coast of the Ratnagiri District, Maharashtra, India. During the pre-monsoon (PRM) season, the foreshore sediments comprise fines and to medium sand, while the backshore, raised beach (Berm) and foredune sediments show fine sand characteristics. The PRM foreshore, backshore, raised beach (Berm) and foredune sediments are well-sorted to moderately well-sorted. The foreshore sediments show symmetrical to strongly fine skewed whereas, backshore sediments are fine skewed to strongly fine skewed. The foreshore and backshore sediments in the post-monsoon (POM) season are comprised of coarse-grained sands, whereas raised beach and foredune sediments contain fine-grained sand. The foreshore sediments are poorly sorted to very poorly sorted, while the backshore and raised beach sediments are moderately poorly sorted. The linear discriminant analysis (LDA) plots of the sediments fall in a shallow marine environment, while few fall in a beach shallow environment. The XRF studies indicate a high concentration of 'Fe' in the northern part while it decreases towards the southern part along the beach. The 'Fe' concentration also increases cross-shore from foreshore to backshore. The 'Ti' concentration also shows an increasing trend from the foreshore to the backshore zone. The mudflat samples have indicated the presence of kaolinite, illite, smectite, and chlorite. The concentration of kaolinite and illite is higher than that of smectite and chlorite from north to south in the study area. The waves and currents along the Gaonkhadi Coast of the Ratnagiri District are formed under high energy conditions during the SW monsoon and affected erosion with a strong winnowing process. Keywords: Grain Size, Linear Discriminant Functions, CM Plots, Depositional Sedimentary Environment, West Coast of India

India is endowed with 3896 million tons of bauxite resources and ranking it fifth globally. The bauxite comprises various minerals such as gibbsite, boehmite, diaspore, hematite, goethite, kaolinite, quartz, anatase and rutile. India possesses abundant lateritic bauxite resources originating from parent rocks like Khondalite, Deccan trap basalt, Granite Gneiss, Sandstone, etc., each exhibiting its specific characteristics. The geotechnological evaluation of India's lateritic bauxite deposits, conducted by Jawaharlal Nehru Aluminium Research Development and Design Centre (JNARDDC), revealed the presence of two types of deposits: high-level and low-level (coastal). In this study, bauxite and laterite samples were collected from different regions in India and subjected to comprehensive technological evaluation. Mineral processing techniques are optimized based on the mineralogical and petrological characteristics of the bauxite deposits. The mineral liberation, association, and alteration information obtained through petrological analysis guide the selection and optimization of various methods. The understanding of the mineralogy and petrological characteristics also assists in predicting the behaviour of bauxite during the processing stages, facilitating process control and minimizing losses. This paper aims to highlight the petrological, chemico-mineralogical characteristics of Indian lateritic bauxite deposits and emphasize the significance of petrology and mineralogy in their evaluation and mineral processing. Microscopic examination plays a vital role in mineral characterization and the beneficiation process by enabling mineral identification, texture analysis, grain size, mineral liberation, association, alteration, and process optimization. Such comprehensive analysis contributes to maximizing the economic value of mineral resources, aiding informed decision-making in exploration, mining, and mineral processing industries. Keywords: Bauxite, Lateritic Deposits, Petrological Characteristics, Mineralogy, Mineral Processing

The chemical composition of groundwater is changed by a number of hydro-geochemical processes. Rock-water interaction is the primary process that controls the ionic concentration of water, even though vaporization, concentration and dilution due to precipitation alter the chemical composition of groundwater. The chemical reactions differ depending on the preliminary composition of water, the geological formations it passes through and even how long it has been there. The 48 groundwater samples used in this study were collected, and the pH, Electrical Conductivity, Total Dissolved Solids, major cations and anions concentrations were measured. Gibb's Plot, Bivariate diagrams, Piper's Trilinear diagrams along with Saturation Indices were used to examine the mechanism of rock-water interaction in Kuzhithuraiyar Sub-Basin. Keywords: Rockwater Interaction, Bivariate Diagrams, Gibbs Plot, Pipers Trilinear Diagram, Saturation Indices

TBM penetration rate prediction models were developed for the hard Archean granites, granite gneisses and Meta-sedimentary rock groups comprising of quartzites, quartz arenites and sandstone of peninsular India.Construction stage engineering geological mapping comprising of face logging resulted in rockmass characterisation of Archeans and Meta-sedimentary rock groups. Statistical correlation of TBM penetration rate (PR) with Rock quality designation (RQD), unconfined compressive strength (UCS), volumetric joint count (Jv) and rockmass class was carried out. The prediction model provides good correlation only in the Meta sedimentary rock group for RQD, UCS and rockmass class and good correlation only for RQD and rockmass class in the Archean group but poor correlation with UCS. There is an exponential increase of penetration rate with Jv in both the rock groups. Keywords: TBM Penetration Rate, Rockmass Characteristics, Geological Mapping, Rockmass Classification, Rock Tunnel

Stable isotopes of oxygen (δ18O) and hydrogen (δ2H) are useful tools to characterize and monitor the hydrological processes in aquatic ecosystems.The present study uses δ18O and δ2H data from two small catchment rivers such as the east-flowing Bhavani river and the west-flowing Thuthapuzha River in southern Western Ghats to get an insight into the water cycle dynamics and sources of water.The Bhavani River drains through the semi-arid, lee-ward side of the Western Ghats and shows a markedly depleted isotopic composition as compared to the Thuthapuzha River which drains through the humid, windward side of the Western Ghats. The isotopic systematics are strongly influenced by the southwest monsoon (SWM) and the northeast monsoon (NEM) rainfalls. However, during the pre-monsoon (PRM) season, the isotopic composition in these river waters is governed mainly by the baseflow and evaporative processes. Both the river basins experience a higher vapour recycling effect in their headwaters. The NEM rainfall contains a considerable amount of recycled vapour, which is evident from the observed high d-excess values. Whereas the SWM rain events show the dominance of the original sea moisture source. There is a distinct difference in the isotopic ratios and d-excess values between the SWM (d-excess: Bhavani River 10.29 ± 1.29‰; Thuthapuzha River 10.52 ± 2.78‰) and the NEM (d-excess: Bhavani River 15.15 ± 0.92‰; Thuthapuzha River 12.67 ± 4.49‰) seasons, with the predominance of lighter isotopes in the latter period. In general, the seasonal and spatial differences in isotopic composition in the Bhavani River (δ18O: PRM−5.42 ± 1.76‰; SWM−4.16 ± 0.77‰; NEM -4.73 ± 0.76‰) and the Thuthapuzha River (δ18O: PRM −4.26 ± 0.67‰; SWM −2.54 ± 0.76‰; NEM −2.68 ± 0.96‰) indicate that precipitation (atmospheric source) as the major source of water in the monsoon (SWM and NEM) season, while the base flow contribution from groundwater has a major stake in PRM season. Keywords: Stable Water Isotopes, d-excess, Climate Gradient, Base Flow Discharge, Western Ghats, Southwest India

The NW-SE trending mafic dykes intrude the Amgaon gneisses and Dongargarh granite in Wairagarh area of the Western Bastar Craton (WBC). These dykes consist of mainly the clinopyroxene, plagioclase feldspar and minor amphiboles and titano-magnetite. These are metamorphosed to green schist facies. The mafic dykes show tholeiitic trend on multivariate geochemical plots and moderate range of variation in SiO2 (50.15 to 52.84 wt.%), MgO (5.13 to 7.64 wt.%), Fe O (12.97 to 15.08 wt.%), Al O (12.74 to 14.48 wt.%) and the Mg# value ranges from 37.74 to 51.21. Strong positive correlation of Sr, Th, Hf, U, Ga, Ta, Pb, Cs, Rb and HREEs negate the effect of post magmatic alteration. Negative Nb, Ta and Ti with positive Zr and Hf anomalies suggest the effect of assimilation and crustal contamination, which is also supported by Ce/Nb (0.23-0.33) equivalent to the crustal value. Negative ΔNb value suggests depleted mantle source for the mafic dykes of the WBC. Restricted range of (Gd/Yb)N (1.05-1.67), (Dy/Yb)N (0.94-1.25) and (Sm/Yb)N (1.22-2.26) advocate that these mafic dykes were derived from spinel lherzolite source. About 5-15% degrees of partial melting of depleted mantle source is envisaged for the generation of the mafic dykes. The field and geochemical evidences suggest that the mafic dykes of Wairagarh area, WBC were emplaced within continental rift environment. Keywords: Mafic dykes, Geochemistry, Wairagarh, Bastar Craton, Central India

Satish G. Udhoji was born on 28.06.1945. He passed B. Sc. in 1965 and M. Sc. in 1967 from Geology Department of Nagpur University, Nagpur. After passing M. Sc, he joined Indian Bureau of Mines in Mineral Exploration Division which later merged with Geological Survey of India (GSI). Initially, he was working in Mineral Exploration for Manganese Ore and transferred later to GSI, Nagpur. At Nagpur, he worked in mineral exploration for few years and was later shifted to the Palaeontology Division. At Palaeontology Division, he worked on palynological study of rocks from Central India. During his stay at Nagpur, he completed LLB in 1987. Besides geology, he had good knowledge of legal matters and he was consulted frequently on legal matters. Later, he was posted to the Publication Division due to skill of meticulous scrutiny of technical matters. He was expertin scrutiny and publication of scientific articles, which was acclaimed all over GSI. His contribution in printing Seminar volume, GSI news and brochure during the celebration of “150 years of GSI” was well appreciated. Later, he was posted to Bengaluru, where he worked as a Head of Office also. He retired from GSI, Nagpur as a Director Publication. He was an active member of GGS, who contributed well during the Seminars, mostly managing publication of proceeding volumes. He was also consulted frequently about legal matters. His demise at the age of 76 years is an unbearable loss to GGS.