Abstract An integrated study utilizing remote sensing, GIS, and high-resolution electrical resistivity tomography (ERT) has been carried out in SriGanganagar district, Rajasthan, in an alluvial plain to assess the prospect and quality of groundwater resources both in the spatial and depth scale. In this present work, remote sensing satellite Shuttle Radar Topographic Mission (SRTM) DEM data with a 30 m spatial resolution is utilized to estimate various thematic layers. In addition, high-resolution ERT mapping was accomplished at nine sites, which distinctly resolved the geological strata up to a maximum depth of 215 m, showing significant resistivity contrast between geological layers and linear features. Resistivity results inferred the fresh groundwater zone lies between 25 and 40 m depths with a resistivity between 10 and 20 Ω.m while <5 Ω.m saturated formation is chiefly responsible for the saline groundwater characteristics, which is non-potable. The results from remote sensing and GIS were studied in concurrence with the electrical resistivity tomography model results and found to be in good agreement for groundwater recharge zonation from very good to poor ratings. In addition, the major water quality parameters, namely fluoride and iron, were studied to assess the groundwater quality from the yearly dataset. The integrated groundwater quality map revealed potable and non-potable zonation, which shows the non-potable area covers 84% despite it showing a good prospect zone while the potable zone covers only 16% of the total area and found moderate groundwater prospect scenario, same as we found from the results of 2D lithosection model. This lithosection model represents the lithological variation of the study area with a total length coverage of 134 km and up to 150 m depth. This study and its results are useful and crucial for the arid region of India, which is beneficial for thoughtful long-term planning, management, exploration strategy, and the development of groundwater resources. Research highlights <UnorderedList Mark="Bullet"> <ItemContent> Remote sensing, GIS, and ERT delineated prospect groundwater zones. </ItemContent> <ItemContent> Strikingly, 2D model resistivity results vary from <1 to 548 Ω.m. </ItemContent> <ItemContent> The near-surface layer up to 20 m depth is delineated as a hard sand layer. </ItemContent> <ItemContent> The range <1 to ~10 Ω.m resistivity is a characteristic of the salinity of the water. </ItemContent> <ItemContent> Groundwater quality: Non-potable 84% and only 16% potable zone of the total area. </ItemContent> </UnorderedList>

Groundwater prospect and quality assessment in arid region, NW India: Implications from weighted overlay analysis and electrical resistivity tomography

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发表日期：

2025年6月14日

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Rishu Pandey,
Dewashish Kumar,
Prem Prakash Dookia

摘要

Abstract

An integrated study utilizing remote sensing, GIS, and high-resolution electrical resistivity tomography (ERT) has been carried out in SriGanganagar district, Rajasthan, in an alluvial plain to assess the prospect and quality of groundwater resources both in the spatial and depth scale. In this present work, remote sensing satellite Shuttle Radar Topographic Mission (SRTM) DEM data with a 30 m spatial resolution is utilized to estimate various thematic layers. In addition, high-resolution ERT mapping was accomplished at nine sites, which distinctly resolved the geological strata up to a maximum depth of 215 m, showing significant resistivity contrast between geological layers and linear features. Resistivity results inferred the fresh groundwater zone lies between 25 and 40 m depths with a resistivity between 10 and 20 Ω.m while <5 Ω.m saturated formation is chiefly responsible for the saline groundwater characteristics, which is non-potable. The results from remote sensing and GIS were studied in concurrence with the electrical resistivity tomography model results and found to be in good agreement for groundwater recharge zonation from very good to poor ratings. In addition, the major water quality parameters, namely fluoride and iron, were studied to assess the groundwater quality from the yearly dataset. The integrated groundwater quality map revealed potable and non-potable zonation, which shows the non-potable area covers 84% despite it showing a good prospect zone while the potable zone covers only 16% of the total area and found moderate groundwater prospect scenario, same as we found from the results of 2D lithosection model. This lithosection model represents the lithological variation of the study area with a total length coverage of 134 km and up to 150 m depth. This study and its results are useful and crucial for the arid region of India, which is beneficial for thoughtful long-term planning, management, exploration strategy, and the development of groundwater resources.

Research highlights

Remote sensing, GIS, and ERT delineated prospect groundwater zones.

Strikingly, 2D model resistivity results vary from <1 to 548 Ω.m.

The near-surface layer up to 20 m depth is delineated as a hard sand layer.

The range <1 to ~10 Ω.m resistivity is a characteristic of the salinity of the water.

Groundwater quality: Non-potable 84% and only 16% potable zone of the total area.