Palaeomagnetism is the study of past variations in the Earthâs magnetic field as reconstructed from the rock and archaeological records.
In addition to providing information about the intensity, polarity, declination and inclination of the Earthâs magnetic field, rock magnetism
also reveals the movements of continents and ocean crust through time.
The record of geomagnetic reversals preserved in volcanic and sedimentary rock sequences (magnetostratigraphy) provides a time-scale that is used
as a geochronologic tool.
Paleomagnetists led the revival of the continental drift hypothesis and its transformation into plate tectonics. Apparent polar wander paths
provided the first clear geophysical evidence for continental drift, while marine magnetic anomalies did the same for seafloor spreading.
Paleomagnetism continues to extend the history of plate tectonics back in time and are applied to the movement of continental fragments, or terranes.
Paleomagnetism relied heavily on new developments in rock magnetism, which in turn has provided the foundation for new applications of magnetism.
These include biomagnetism, magnetic fabrics (used as strain indicators in rocks and soils), and environmental magnetism.
Instruments:
- Thermal Demagnetiser
- Dual speed Spinner Magnetometer (JR â 6)
- AF Demagnetiser (LDA - 3A)
Existing Locations:
GSI, CR, Nagpur
Additional Director General & HOD
Central Region
Geological Survey of India
GSI Complex, Seminary Hills,
Nagpur-440006, Maharashtra
FAX-0712-2511671
Email-hod.cr@gsi.gov.in
