Delineation of Holocene–Pleistocene aquifer system in parts of Middle Ganga Plain, Bihar, Eastern India through DC resistivity survey

Shuva Shankha Ganguli,Shashikant Singh

doi:10.1007/s13201-014-0220-8

Abstract

The study area forms a part of the Middle Ganga Plain (MGP) and experiences intensive groundwater draft due to domestic, irrigation and industrial purposes. Geoelectrical surveys were carried out in a geomorphic unit of MGP called South Ganga Plain, along the north–south traverse covering a total 50 km stretch. Interpreted results of the total of 17 vertical electrical soundings, carried out, provided information on aquifer and aquitard geometry and sediment nature in different aquifer systems. Bedrock topography is also demarcated along the north–south transect. The estimated dip of massive bedrock is less than 0.5° and dips toward north. The survey results show that a two-tier aquifer system exists in Newer alluvium parts of the study area and it is replaced by a single aquifer system at Older alluvium that occurs under thick clay/sandy clay bed in the southern part. An exponential decay of the aquifer potential is observed from north to south. Paleo channel Sone River is traced and it forms a potential aquifer.

Highlights

The Gangetic Plains of India are intensively populated (*250 million) and irrigation has always been central to life and society in general
The survey results show that a two-tier aquifer system exists in Newer alluvium parts of the study area and it is replaced by a single aquifer system at Older alluvium that occurs under thick clay/ sandy clay bed in the southern part
Newer and older alluvium boundary is traced along the traverse and it is slightly south of Gopalpur Mathai

Summary

Introduction

The Gangetic Plains of India are intensively populated (*250 million) and irrigation has always been central to life and society in general. The study area (Fig. 1b, c) forms a traverse of the South Ganga Plain (SGP), a major geomorphic unit of the Middle Ganga Plain (MGP) for about 51 km length, stretched in the north–south direction through Patna and Jehanabad districts. A major structural high Munger-Saharsa ridge (Fig. 1d) forms the south-western boundary of the study area while north–south aligned Sone River and east–west aligned Ganga River form the eastern and northern boundaries, respectively. Aquifer geometry and hydraulic properties in the older alluvium further east of the study area, in Nalanda District, were studied (Raja et al.2003; Saha et al 2007; 2009a, b).The Quaternary deposits in South Ganga Plain (SGP) lie unconformably over the northerly sloping bedrock and are not influenced by marine transgression (Tandon et al 2008).

Section I: Sripatpur to Abdhara

Section II: Dhanarua to Masauri

Section III: Gopalpur Mathai to Mai

Findings

Discussion

Conclusion