Integrated geophysical and geochemical assessment of submarine groundwater discharge in coastal terrace of Tiruchendur, Southern India

J Vinoth Kingston,A Antony Ravindran,A Antony Alosanai Promilton,S K Aswin,S Richard Abishek

doi:10.1007/s13201-021-01553-8

Abstract

Submarine groundwater discharge (SGD) study is essential for groundwater in coastal terrace at Tiruchendur. The famous Murugan Temple is located in the area and around 25,000 people who visit this temple use the SGD well water at NaaliKinaru (a small open well) as holy water and drink it. The rock and soil type are sandy clay, silt, beach sand, calcarenite, kankar, gneissic rock and charnockite in base rock. Megascopic identification method was used to identify the porous and permeable rocks such as calcarenite, sandstone and kankar to support to increase SGD flux. Grain size study was used to identify the paleo-coastal estuarine environment with sediment deposits in the terrace. The square array electrical resistivity method was used to study the subsurface geology and aquifer depth. The 2d ERT technique was used to identify the subsurface shallow perched aquifer of freshwater. The magnetotelluric survey method was used to scan the entire subsurface geological and tectonic uplift, coastal ridges, rock folded subsurface structural features of continental and oceanic tectonism. Darcy’s law was used to calculate the SGD flux rate in the above study area.

Highlights

The submarine groundwater discharge (SGD) study plays a major play role in the coastal aquifer and water resources management
This study focuses on SGD in porous sandstone with water permeability for public utility
The floating of freshwater (SGD in the form of perched aquifer) oozed out to occur in the seaside area of the Murugan Temple in Tiruchendur

Summary

Introduction

The submarine groundwater discharge (SGD) study plays a major play role in the coastal aquifer and water resources management. Studying the SGD discharge with flux rate estimation is essential one for coastal zones monitoring of freshwater environment. Porubsky (2014), Burnett et al (2006), The SGD discharge with flux rate estimation is essential one for monitoring of freshwater environment in coastal zones. Zhang et al (2020), Duque et al (2020). Aquifer characteristic study is essential for SGD flux estimation. An estimation of freshwater discharge using electrical resistivity methods of 2D ERT and magnetotelluric method. Ma and Zhang (2020), George et al (2018), Jeyapaul et al (2020), Ravindran et al (2021). Geochemical studies were carried out by some researchers, Selvam et al (2021a, b)

Methods

Discussion

Conclusion