Monitoring geomagnetic signals of groundwater movement using multiple underground SQUID magnetometers

Groundwater can influence the geomagnetic field measured underground in at least two key ways. The water levels in rock will determine its electrical conductivity, and thus change the magnitude of the telluric currents induced in the rock by changing magnetic fields generated in the ionosphere. This...

Full description

Saved in:
Bibliographic Details
Main Authors: Henry, S., Pozzo di Borgo, E., Danquigny, C., Cavaillou, A., Cottle, A., Gaffet, S., Pipe, M.
Format: Conference Proceeding
Language:English
Subjects:
Complex systems
Electrical conductivity
Electrical resistivity
Electrokinetics
Fluxgate magnetometers
Geomagnetic field
Geomagnetism
Groundwater
Groundwater flow
Ionosphere
Karst
Magnetic fields
Magnetic measurement
Magnetometers
Rocks
Signal monitoring
Superconducting quantum interference devices
Telluric currents
Water levels
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Groundwater can influence the geomagnetic field measured underground in at least two key ways. The water levels in rock will determine its electrical conductivity, and thus change the magnitude of the telluric currents induced in the rock by changing magnetic fields generated in the ionosphere. This can be studied by using multiple magnetometers at different underground locations. Secondly the flow of water through rock will generate a small magnetic signal, of unknown magnitude, through the electrokinetic effect. SQUID magnetometry has the potential to allow passive studies of groundwater changes in complex systems such as karst. We have monitored geomagnetic signals using two SQUID magnetometers at the LSBB underground laboratory, and set an initial limit on the magnitude of the electrokinetic signal. We now plan to carry out a longer term measurement using three SQUID systems as well as fluxgate sensors to track changes in the gradient of the magnetic field across the underground complex.
ISSN:2267-1242
2555-0403
2267-1242
DOI:10.1051/e3sconf/20140402004