SOLID EARTH GEOMAGNETISM
Geophysics plays a major role in the understanding of the earth’s interior, as well as in mineral and oil exploration. More often than not, the geophysical targets are not accessible for direct observation and hence the target is characterized by the manifestations of its physical properties, such as, the density (Gravity techniques) reflections at the boundaries (natural and artificial source seismic studies), temperature (Heat Flow studies), magnetic properties (Magnetic anomaly maps and palaeomagnetic techniques) and the electrical structure (Magnetotelluric and other electromagnetic techniques). These different studies are put together to identify the nature of the target. The major thrust areas of research under Solid Earth Geophysics are
ELECTROMAGNETIC INDUCTION STUDIES:
Electromagnetic induction based tools such as magnetovariational and magnetotelluric techniques are used for imaging electrical conductivity structures in the interior of the Earth and studying their geophysical implications, and utility as geophysical exploration tools.
Monitoring of the total geomagnetic field in the vicinity of fault (Jabalpur area) to detect changes in the static part of geomagnetic field due to general tectonic activity and crustal stress accumulation with a view to understanding an earthquake mechanism.
Satellite, aeromagnetic, and ground geomagnetic data are used to study magnetic anomalies in the Indian lithosphere and to relate these to geotectonic processes.
CRUSTAL DEFORMATION STUDIES:
Radio wave signals from the Global Positioning System (GPS) satellites and Synthetic Aperture Radar (SAR) Interferometry is used to study the deformation of Earth’s crust in the Indian region.
IIG has a full-fledged, state-of-the-art laboratory at DR. KSKGRL, Allahabad for Palaeomagnetic studies, with a Magnetic Vacuum System (MAVACS) for thermal cleaning of rock samples.
Mineral magnetic properties of sediments are used as proxy indictors for studying past (palaeo) and present environmental changes of soil magnetism, climate, pollution, and mapping of human impact on the environment. Such mineral magnetic methods are being applied to Indian lake/deltaic/sea sediments (lake/deltaic/sea) and soils for obtaining information of past-environments and past-climates in tropical India.
Theoretical study of the evolution of the main magnetic field using geodynamo models, and observed secular variation in the geomagnetic field derived from long term data recorded at magnetic observatories and recent satellite data.