Rock Terrain Research Articles

Groundwater quality assessment using water quality index (WQI) under GIS framework

Groundwater is an important source for drinking water supply in hard rock terrain of Bundelkhand massif particularly in District Mahoba, Uttar Pradesh, India. An attempt has been made in this work to understand the suitability of groundwater for human consumption. The parameters like pH, electrical conductivity, total dissolved solids, alkalinity, total hardness, calcium, magnesium, sodium, potassium, bicarbonate, sulfate, chloride, fluoride, nitrate, copper, manganese, silver, zinc, iron and nickel were analysed to estimate the groundwater quality. The water quality index (WQI) has been applied to categorize the water quality viz: excellent, good, poor, etc. which is quite useful to infer the quality of water to the people and policy makers in the concerned area. The WQI in the study area ranges from 4.75 to 115.93. The overall WQI in the study area indicates that the groundwater is safe and potable except few localized pockets in Charkhari and Jaitpur Blocks. The Hill-Piper Trilinear diagram reveals that the groundwater of the study area falls under Na+-Cl−, mixed Ca2+-Mg2+-Cl− and Ca2+-{text{HCO}}_{3}^{ - } types. The granite-gneiss contains orthoclase feldspar and biotite minerals which after weathering yields bicarbonate and chloride rich groundwater. The correlation matrix has been created and analysed to observe their significant impetus on the assessment of groundwater quality. The current study suggests that the groundwater of the area under deteriorated water quality needs treatment before consumption and also to be protected from the perils of geogenic/anthropogenic contamination.

Characterization of weathering profile and quality of groundwater over hard rock terrain

In this study, we present a detailed characterization of weathering profile and groundwater over a hard rock terrain showing the formation of kaolinite, groundwater quality assessment, and hydrogeochemistry. The crystal structure, chemical composition, and spectral characteristics of a weathering profile collected from Thiruvananthapuram district, the southern part of Kerala, India, were studied using XRD, ED-XRF, TG-DTA, UV-Vis-NIR, XPS, and FTIR spectroscopy. The physicochemical parameters of the groundwater were determined and evaluated for the groundwater suitability for drinking, irrigation, and industrial purposes based on the values of total hardness, TDS, corrosivity ratio, RSC, SAR, USSL classification, saturation index, and Schoeller and Stuyfzand classification derived using “HYCH” program. Interpretation of the results shows that the groundwater is suitable for drinking, irrigation, and industrial purposes. The characterization of the profile samples reveals that the aquifer is a weathered profile with the formation of kaolinite mineral at the bottom. The results show that the hydrogeochemical processes that exist in the present study area are controlled by precipitation, not by rock–water interaction or evaporation, which suggests that the groundwater chemistry is not influenced by the aquifer minerals.

A GIS-based assessment in drainage morphometry of WRJ-1 watershed in hard rock terrain of Narkhed Taluka, Maharashtra, Central India

Study area consists of catchments of Wardha river tributaries like Madar River, Jam River and a Wainganga river tributary viz. Chandrabhaga River as the principal drainage area. It extends between N 21°15′ to 21°32′ latitude and E 78°23′ to 78°39’ longitude covering an area of about 252.25 sq. km administratively covering Narkhed taluka of Nagpur district. The NW part mainly of Deccan traps consist of slightly-moderately dissected plateaus. The southern section of Narkhed taluka is composed of gravelly sandy to sandy loam soil while the Gondwana sandstones mostly appear in east of the study region. The study aims at assessment of drainage morphometry of WRJ-1 watershed. Permeability within subsoil of watershed is high with a distinct lesser discharge rate. The watershed was divided into nine sub-watersheds viz. W-1, W-2, M-1, M-2, M-3, M-4, C-1, J-1, and J-2. The sub-watersheds were subjected to morphometric analysis and corresponding linear, areal, relief parameters along with some geomorphic indices of neo-tectonics were computed whose resultants could be treated in GIS environment with landuse/landcover, geology, soil data to locate areas under immediate effect of resource conservation measures for sustainable development and management of natural resources to formulate conservation ideas. Additionally, this study will also help to calculate volume of rivers, tributaries in WRJ-1 thereby forecasting changes in the sediment transport.

Groundwater exploration in hard rock terrains of East Godavari district, Andhra Pradesh, India using AHP and WIO analyses together with geoelectrical surveys

<abstract> The need for groundwater exploration in India has been increasing enormously, due to the non-judicial use of available water resources. The present study area is located between longitudes from 81°52′20.293′′ to 82°29′32.058′′ E and latitudes from 17°01′6.71′′ to 17°38′ 12.906′′ N in the Eastern Ghats mobile belt region of East Godavari district. The study area is characterized by a wide range of geological settings and high and irregular topographic features. The area is identified by Government as highly backward and Tribal people dwell here. For exploring good aquifer in the study area, the information of ten parameters together with geoelectrical resistivity data has been collected. Analytical Hierarchy Process (AHP) is used as the decision-making technique which uses the weights of different thematic layers (parameters) favorable for groundwater recharge, storage and location. Various thematic layers (parameters) of geology, geomorphology, soil, slope, lineament density, drainage density, groundwater level, Land use/Land cover, rainfall and coefficient of electrical anisotropy were considered in this analysis. A comprehensive groundwater prospect map has been prepared and validated with aquifer thickness map derived from the analysis of geoelectrical data. The entire study area has been classified into different potential zones of good, moderate and poor for groundwater exploration. The good groundwater potential zone is covering an area of 750.91 sqkm (28.4%) with aquifer thickness varying in the range 40–140 m, moderate potential zone encompasses 46.1% of the study area with an areal extent of 1220.33 sqkm and aquifer thickness is about 20–40 m. The remaining area of 24.5% is poor aquifer zone with thickness less than 20 m. </abstract>

Structural interpretation of magnetic and satellite remotely sensed data of Osun State, Southwestern, Nigeria

ABSTRACT This study delineates surface and subsurface structural features in the hard rock terrain of Osun State using magnetic data and satellite remote sensing imageries. To achieve this aim, several image enhancement methods were applied to the magnetic data and satellite remotely sensed imageries to improve visualization and interpretation. The subsurface lineaments were detected and traced out from the maxima of Horizontal Gradient Magnitude, peaks of Analytical Signal Magnitude, and an Euler solution of Osun state. The magnetic lineament map reveals that the structural trend in the area is dominant by NE-SW and NNE-SSW. These structural trends were found to be consistent with the regional tectonics of the Southwest Basement of Nigeria. The NE-SW is the most conspicuous structural trend in the study area. The satellite imageries depict a characteristics feature of the occurrence of underlying structures in the basement complex of Osun State. The major lineament trends delineated in the composite surface lineament map are the NE-SW, NNE-SSW, and ENE-WSW directions. The 2.5 D model across the unmapped lineaments confirmed the existence of a thin dyke’s characteristic of fracture/fault in a typical basement complex terrain. The derived lineaments may serve as a reference for future geological and structural mapping.

Drainage Morphometric Investigation of Nimni Watershed, Chhatarpur District, Madhya Pradesh, India

The present paper deals with drainage morphometric investigation of Nimni watershed, Chhatarpur District, Madhya Pradesh, India. A morphometric analysis of the Nimni watershed has been carried out to characterize the nature of drainage network. The linear, areal and relief aspects of the drainage basin have been determined. The morphometric parameters have been computed on the basis of drainage map prepared on 1:50,000 scale. These parameters includes Stream order, Lengths of stream, Bifurcation ratio, Drainage density, Length of overland flow, Stream frequency, Form factor, Circulatory ratio, Elongation ratio, Lemniscate’s ratio, Basin relief, Relief ratio, Ruggedness number and Ground surface slope. The drainage area of the Nimni watershed is 98 km2. The stream order of the basin is mainly controlled by physiographic and lithological conditions of the area. The increase in stream length ratio from lower to higher order shows that the study area has reached a mature geomorphic stage. The geomorphic analysis of Nimni watershed reveals that the present drainage basin exhibits uneven topography, presence of hard rock terrain and dendritic to sub-dendritic drainage pattern. The dendritic drainage pattern exhibits the presence of hard and resistant rocks referable to Bundelkhand Granite Complex.

Assessment of Groundwater behavior in Kulpahar Watershed, District Mahoba, Uttar Pradesh, India

In hard rock terrain, the groundwater occurs in two zones viz. shallow zone (in overburden) and deeper fractured zones mainly through secondary porosity. The groundwater level through 23 observation wells (fifteen dug wells and eight piezometers) has been monitored during pre and post-monsoon periods. An attempt has been made to evaluate the impact of rainfall on the groundwater level in the hard rock area of Mahoba district in the Bundelkhand region. The study depicts the impact of rainfall over the long-term groundwater level trend and establishes a conceptual structure to understand the hydrological stress conditions. Due to overexploitation, the groundwater condition has reached to the category of a critical stage. The severity and duration of water-level responses to hydrologic stresses have been analyzed statistically as well as graphically. The groundwater level is spatially and temporally variable in hard rock area and essentially depends upon the amount of rainfall, geological condition, and topographic slope. The analyzed rainfall data have been graded as a good year and bad year based on the amount of precipitation. The long-term groundwater level trend (2006-2016) indicates a sharp decline in groundwater level trend in the western part due to higher base flow and poor recharge. On the other hand, due to the presence of thicker overburden and runoff accumulation therein, the groundwater level is rising in the northern part of the study area. It also validates that there is very fair control of slope and thickness of overburden on the groundwater regime apart from the rainfall.

Geospatial applications in delineating groundwater prospect zones in a hard rock terrain: an integrated approach

This study involved the application of geospatial techniques to delineate groundwater potential zones in a hard rock terrain of Oban Massif and environs. This goal was achieved using satellite remote sensing imagery and geographic information system techniques. The method mapped groundwater-controlling factors such as geology, geomorphology, lineament density, slope, land use and land cover and drainage density. The study covered a total area of 677,298 km2. Landsat ETM+ imagery, Shuttle Radar Transmission Mission (SRTM), topographic and geological maps and ASTER DEM were used in the analysis. Software used for image processing, digitizing and lineament density computation are ArcGIS10.1, ENVI 4.2 and PCI Geomatica, respectively. Supervised classification method was applied in land use and land cover mapping. Analysis of satellite imagery shows that band 4 was the best for showing textural features for lineament extraction. The method of multi-criteria evaluation by assigning relative weights to each groundwater-controlling factor was used to produce their corresponding thematic maps. The thematic maps were produced by weighted linear combination; each class individual weight was multiplied by the map scores and then adding the results. Overlay analysis of the thematic maps produced the groundwater potential map. Results show four groundwater prospect zones classified into very good (38,365 km2), moderately good (230,999 km2), fair (381,865 km2) and poor (26,068 km2). From this study, it is evident that lineament mapping is not the overriding factor in groundwater occurrence; other groundwater controlling factors are necessary for a more credible groundwater potential modeling. Lineament, slope, geology and geomorphology are the most influential groundwater controlling factors in the study. Comparison of the results of this study with the collected sample data shows reasonable accuracy. These findings are useful for borehole siting and environmental management strategies for groundwater potential investigation in both Nigeria and other parts of world.

Delineation of Groundwater Potential Zones using Integrated Approach in Semi-Arid Hard Rock Terrain, Kanavi Halla Sub-Basin, Belagavi District, Karnataka

Abstract Water scarcity has become a major problem especially in arid and semi-arid regions due to insufficient rainfall throughout the globe. This has led in serious search for groundwater resources. Kanavi Halla Sub Basin (KHSB) of Ghataprabha River basin drained by Ghataprabha River, Belagavi District of Karnataka state in India has been considered for present study. Electrical resistivity survey was carried out at selected sites using Schlumberger method with four electrode configuration. A total of 22 Vertical Electrical Sounding (VES) were conducted throughout KHSB and representative of different litho units were considered. Data obtained were then interpreted using curve matching technique with IPI2Win software. The interpreted graphs show three to six layers. The various interpreted curve types are of AAK-type, HA-type, A- type, KH-type, HAA-type, KQH-type, AK-type, K-type, HQH-type, H-type and AKQH-type. From the results it shows that the maximum number of curves are associated with A type which refers to hard rock terrain, whereas curve associated with H type indicates water potential site. The expected subsurface strata are interpreted on the basis of observed bore well drilling data. Borewell log reveals soil formation followed by moderately weathered formation, weathered jointed formation, jointed formation, hard formation from top to bottom. Further deep, the formation is devoid of joints and fractures. Therefore, the weathered, jointed formation may be interpreted as water bearing zone. 2-D geo-electric section has been drawn using IPI2WIN over eight selected trends to understand the geometry of the aquifer formed. The investigation was meant to characterize the aquifer in KHSB along with the risk assessment for contaminants through seepage in terms of protective capacity with the help of Dar-Zarrouk (D-Z) parameters such as longitudinal unit conductance (S), longitudinal resitivity (ρl), transverse unit resistance (T), transverse resistivity (ρt), Electrical anisotropy(λ) and root mean square resistivity (ρm). These were evaluated to know the aquifer conditions in order to demarcate the freshwater bearing zones. South eastern part of KHSB might be contaminated and 30% of the area is weak to poor capacity protective zone for contaminants. The work adequately highlights the practical use of geophysical techniques, combination of geo-electrical modelling, D-Z parameters, borehole log in the groundwater resource assessment process. This technique is highly recommended for the area with similar geological setup.

Enhancement of groundwater yield by hydrofracturing technique: A case study from crystalline hard rock terrain

Hydrofracturing process was developed during the 1940s for improving the yield from oil and gas wells. Later this technique was adopted for water well development. The hydrofracturing process consists of pumping test before and after fracturing a well. The pre-fracturing and post-fracturing pumping test results are analysed and correlated to estimate the yield improvement realized due to fracturing. An attempt was made to improve the groundwater yield from a borewell in hard rock formation in Thachchur Village of Cuddalore District, Tamil Nadu, India. The pre-pumping static water level was 4.25 m below measuring point (bmp), and the safe yield was 5 litres per minute (lpm)/16 m drawdown/8 h of pumping per day. Hydrofracturing was carried out using a single packer assembly system, and two fracture zones lying at the depth of 15 m and 45 m were treated. After fracturing treatment, pumping test was carried out. Post-fracturing pumping test results revealed that the safe yield was 80 lpm/16 m drawdown/8 h of pumping per day. The yield improvement from 5 to 80 lpm substantiated the success of hydrofracturing in the hard rock borewell. The groundwater yield improvement in the borewell is due to the enlargement of fissures and cracks in and around the borewell by hydrofracturing.

Groundwater chemistry integrating the pollution index of groundwater and evaluation of potential human health risk: A case study from hard rock terrain of south India

Groundwater is an important resource for drinking and irrigation purposes and also the significant route of human exposure in most of the arid and semi-arid regions of the world. In view of this, 43 groundwater samples were collected and analyzed for various physico-chemical parameters. Particularly, this study integrates the groundwater contamination by comparing it to national guidelines and the impact of fluoride and nitrate on health risk were quantified through the model recommended by the United States Environmental Protection Agency (USEPA). The groundwater of the investigated region is slightly alkaline in nature with hydrochemical facies of groundwater is predominantly characterized by Ca2+-Mg2+-HCO3- and Ca2+-Mg2+-Cl- water types. The results show that the concentrations of groundwater nitrate and fluoride range from 2.2 to 165 mg/L and 0.84 to 4.3 mg/L, and 55.81% and 65% of groundwater exceed the national guidelines for drinking purposes, respectively. The pollution index of the groundwater (PIG) method unveiled that low quality and moderate quality of water account for 40% and 4.65% of collected groundwater samples, respectively. The results of non-carcinogenic health risk ranged from 0.63 to 5.31 ± 2.59 for adults, 0.85 to 7.18 ± 3.50 for children and 0.98 to 8.29 ± 4.04 for infants, indicating health risk was higher in infants and children as compared to the adults in the study region.

Factors controlling the distribution of radon (222Rn) in groundwater of a tropical mountainous river basin in southwest India

Studies on occurrence of radon in the environment are receiving growing attention worldwide due to its adverse impact on human health. Despite that, the dissolved radon in water is found to be a useful tracer in many hydrogeological studies. Although, several studies focused on the occurrence of high 222Rn in groundwater, the processes responsible for its variation is still not well understood. Hence, an attempt has been made in the present study to elucidate the underlying factors influencing the abundance 222Rn in hard rock (gneissic) aquifers of Karamana River Basin, southwest India. 222Rn in groundwater was analyzed in 71 dug wells during the pre-monsoon period of 2017.A large variability in 222Rn activities (170–68,350 Bq/m3) was noticed in groundwater and high activities were mainly seen in the khondalite formation. No significant dependencies between 222Rn activity and depth to water table, groundwater temperature and electrical conductivity were observed. However, majority of the presence of high 222Rn activity in groundwater matches with the location of lineaments. Furthermore, radium content in the host rock, degree of weathering and fracturing and the emanation coefficient of the rock were found to have an important bearing on the occurrence of radon in groundwater. The underlying factors influencing the abundance of radon in hard rock aquifers were also conceptualized. Thus, the study highlights the usefulness of 222Rn as a potential tool in delineating the macro-structural features like fractures/lineaments that are significant repositories of groundwater, which could be explored for groundwater development in hard rock terrains.

Filtering of hydraulically significant lineaments from lineament map of precambrian metamorphic terrain in NE India using set theory

Identification of hydraulically potential lineaments directly from lineament map required for studies of groundwater resource development in crystalline metamorphosed rock terrain, which is considered as a poor groundwater province area, is a big challenge. Lineament study from satellite image gives all available lineaments present in the location including the hydraulically potential lineaments. But there are no existing methods present at our disposal which can detect only the hydraulically potential lineaments. This study attempts to delineate the hydraulically significant lineaments those are actively promoting groundwater flow in Purulia district, West Bengal, NE India, where the exposed rock-types are porphyritic granite gneisses, quartzite, mica schist, garnetiferous-sillimanite-biotite schist and phyllite, using Set theory. For the study, standard FCC image setup has been used to view the satellite imagery on computer screen within Erdas Imagine software and lineaments are examined visually on-screen, without taking any print out of the map. The azimuth directions of the lineaments are diagrammed using GEOrient software. Azimuth rose diagrams of the trend of foliation planes and fracture planes, obtained from direct measurement at rock exposures, are compared with the lineament trends to yield hydraulically significant lineaments, concordant to the trends of hydraulically significant fractures. Hydraulically significant lineaments are filtered from the total lineament map by using the laws of set theory, like universal set, sub-set, union, intersection, subtraction and equality. Validation of the obtained result with ground truth reveals that intense deformation of brittle rocks, that allow fluid movement, have a significant role in the development of hydraulically significant lineaments. This study successfully distinguishes the hydraulically significant lineaments, exhibiting a directional concurrence to hydraulically significant fractures, implying that set theory can be successfully used to extract hydraulically significant lineaments directly from lineament map.

Mapping of Groundwater Potential Zones in a Crystalline Terrain Using Remote Sensing, GIS Techniques and Field Observations: A Case Study in Parts of Tanah Merah, Kelantan, Malaysia

Identification of potential groundwater exploration sites is a difficult activity in hard rock terrain. Groundwater occus in hard rocks at secondary porosity dvoped due to weathering, fracturing, faulting, etc., and this is highly unpredictable and varies dramatically within very short distances, leading to the near-surface aquifer. Topographic, hydrogeological, and geomorphological features in these cases offer valuable clues for the identification of the appropriate location. The present investigation is confined to latitude 5° 45’ 10.508” N and 5° 47’ 53.309” N and longitude 101° 56’ 29.001” E and 101° 59’ 12.249” E. All across Telaga Bijih Area, Tanah Merah, Kelantan, this research focuses on the terrain investigation of groundwater potential zone by applying the geological mapping method and Geographical Information System (GIS) analyses. Briefly, derived from satellite imagery, topographic, geomorphological and hydrogeological observations, promising locations were delineated in hard rock areas of Telaga Bijih village and its surroundings. Several thematic layers including lineament density, lithology, drainage density, and slope density were created for this purpose using the Geographic Information System ( GIS) application to generate groundwater potential zonation map. The final map of groundwater potential plays a key role while narrowing down the selection of potential zones in the study area. The present investigation is very significant in pinpointing the sites for the establishment of new groundwater wells. The areas in north-western and south-eastern parts around Kelisar, Gual and Air Chanal villages are very promising for groundwater exploration. The establishment of new wells will not only make sure the continuous supply of water to the local people but can also be exported to the other places in the vicinity, thus can prove pivotal in revenue generation.

Fluoride enrichment in groundwater and associated human health risk in a tropical hard rock terrain in South India

This study is conducted in Dharapuram, a water-stressed semi-arid region in south India with an aim to understand the hydrochemistry of F-rich groundwater and perform a systematic human health risk assessment. Results indicate that groundwater is alkaline, dominated with Na, Mg, HCO3, and Cl. Gibb’s plot shows that groundwater is influenced by rock–water interaction and evaporation processes. The concentration of fluoride exceeded the acceptable limits of 1 mg/L of Indian drinking water standard in 73% of the samples. However, no samples exceeded maximum permissible limit of 1.5 mg/L. Higher concentrations were observed in the eastern, southeastern, northeastern regions in this category. Geochemical investigation showed that the Na-rich–Ca-poor groundwater favoring fluoride release from the geological formations and increase in F-levels in groundwater. Saturation indices show that groundwater is undersaturated with fluoride, which is agreed with the hydrochemical analysis. Hazard quotient (HQ) shows that the groundwater is posing noncarcinogenic threats to 62% of children and 34% of females. In contrast, men were found to be safer than compared to the other two groups. The individuals with higher body weight are proved to be less affected by the same concentration of fluoride in drinking water.

Application of geological and electrical resistivity methods for groundwater studies at Tatiko, North Central Nigeria

The success probability of water wells constructed in crystalline rock terrains is largely dependent on the size, location and interconnectivity of the fractures present in them as well as the amount and nature of the material that may clog the fractures. Geological and geoelectrical studies were proposed and conducted at Tatiko to determine the structures in the underlying basement rocks and evaluate their groundwater potential. Geological study was used to delineate the structural control on groundwater availability while the geoelectrical study (Vertical Electrical Sounding) was used to investigate the properties of the subsurface materials and determine their potential to host sufficient quantity of groundwater.Structural data were plotted on a rosset diagram and showed major structural control trending in the NW – SE direction. Quantitative interpretation of the geoelectric data indicates that the major fractures are within the weathered to competent basement indicating good hydraulic connection between the weathered and fresh basement. The fractures are deepest within the region that showed thicker weathering and are as shallow as 7 meters in other regions. Apparent resistivity of the fractures ranges between 100Ωm and 1200Ωm in most parts of the area with the highest values in the west. An integration of the result clearly showed that the NW and SW parts of the study area are the most favourable for drilling and further groundwater studies and drilling is recommended to a depth of 40m to 50m.&#x0D; Keywords: Groundwater, Geoelectrical study, Fractures, Tatiko, Resistivity, Basement Complex.

Assessment of groundwater quality using water quality index (WQI): A case study of a hard rock terrain in Sri Lanka

Chronic Kidney Disease of uncertain etiology (CKDu) is a widespread health issue in rural dry zone regions in Sri Lanka. Monaragala region, located in eastern Sri Lanka is one of the hardest hit areas with CKDu. In order to investigate the possible relationship between the incidence of CKDu and drinking water quality, 99 groundwater samples from deep boreholes and shallow wells in hard rock aquifers in the Monaragala region, were collected and analysed for major cations and anions, and some selected trace element contents. The results revealed that over 65% of the groundwater samples from Monaragala area were alkaline. The anions in groundwater varied as HCO3− > Cl− > SO42− > F− while cations varied in the order of Na > Ca > Mg > K. The Majority of the samples (75%) belong to the Ca2+-Mg2+- HCO3− type. Among the studied parameters, electrical conductivity, chloride, sulphate, hardness, fluoride exceeded the WHO recommended values for drinking water in most cases. For instance, 76% of wells in the study area showed fluoride levels higher than the recommended levels (0.5 mg/L) for Sri Lanka. The higher ion contents in groundwater were mainly due to dissolution of aquifer minerals and a higher rate of evaporation. The calculation of Water Quality Index (WQI) indicated that over 50% of groundwater samples of the study area are poor in quality. The higher values of WQI also overlap with high prevalence areas of CKDu. This work revealed that groundwater quality has a direct effect on the etiology of CKDu in the region.

Impact of hydro-geological environment on availability of groundwater using analytical hierarchy process (AHP) and geospatial techniques: A study from the upper Kangsabati river basin

The upper Kangsabati river basin is situated on the extended part of ‘Chhotanagpur Granitic or Granite Gneiss Complex’ (CGGC) of West Bengal and Jharkhand. People of this hard rock terrain suffer severely from water scarcity during scorching summer. To delineate groundwater potential zones of the study region, seven hydro-geological factors, such as geology, lineament, slope, drainage, rainfall, soil and land use land cover are considered. The Cartosat-1 DEM of IRS, LISS-3 image of IRS, geological map of GSI, soil map of NBSS&LUP and rainfall data of CWC are arranged and processed in ArcGIS, Erdas Imagine and PCI Geometica softwares as per requirements to prepare seven individual thematic layers. To assign proper weight of an individual factor based on its level of influence in the occurrence of groundwater, the AHP model is adopted to serve the purpose. Finally, the map of the groundwater potential zones is produced by integrating all the seven layers into one in ArcGIS software. The map of groundwater potential zones of the upper Kangsabati river basin shows that an area of 1819.45 km2 (53.33%) is of good to very good potentiality of groundwater. Only an area of 591.23 km2 (17.34%) is identified as very poor to poor zones of groundwater prospect. The verification of the study is also done by computing an accuracy assessment. The result of the overall accuracy assessment of the study is recorded to be 79.77%, while the Kappa co-efficient is calculated to be 0.73.

Identification of suitable sites and structures for artificial groundwater recharge for sustainable groundwater resource development and management

Artificial recharge is the process of augmentation of the natural infiltration of precipitation or surface water into aquifers by some methods of construction, spreading of water or by artificially changing natural conditions. Upper Betwa watershed, has been taken under study is a semi-arid region, part of Obedullahganj block, Raisen district, M.P., India. The area is hard rock terrain with rugged topography and varying geology. Long term analysis of groundwater level conducted by CGWB, Bhopal has shown sharp decline in groundwater level from past one decade. To increase the groundwater potential of the area, action plan for artificial groundwater recharge has been developed using remote sensing and GIS techniques. Survey of India toposheet no's 55 E/8, 55 E/12, 55 F/5 & 55 F/9, GSI, 2002 resource map, LANDSAT 8, and SRTM (DEM) satellite data and NBSS&LUP soil map were processed in ArcGIS to prepare the various thematic layers viz. Geology, geomorphology, topography, soil, land use/land cover, slope, lineament, drainage and drainage density. Sub-watershed wise action plan of the area has been developed for the area using these thematic layers following the criteria given by NRSA, 1995. In the action plan, development of water harvesting structures (Check dam, Nala bund, Contour bund, Gully plug etc.) were proposed. These structures will provide a measure of artificial recharge in this hard rock terrain by collecting of the surface runoff and increasing the surface area of infiltration. Further, the developed action plan addresses identification of sites for groundwater recharge, through the anticipated artificial recharge structures. Thus, it is suggested that execution of the proposed sub-watershed wise action plan will help in development and management of groundwater resources of the area. Excavation of the proposed structures at their suitable sites identified will enhance the groundwater recharge potential of the area.

Assessment and Mechanism of Fluoride Enrichment in Groundwater from the Hard Rock Terrain: A Multivariate Statistical Approach

Assessment and Mechanism of Fluoride Enrichment in Groundwater from the Hard Rock Terrain: A Multivariate Statistical Approach