Geomagnetism: A property of magnetically susceptible minerals to get aligned to the earth’s magnetic field during the period of the rock formation.
It refers to the Earth’s magnetic field, which expands from the Earth’s center to where it meets the solar wind. The Earth’s magnetic field (or geomagnetic field) is an ever-changing incident that manipulates human activity and the innate world in numerous ways. The Earth’s magnetic field is principally a geo-axial dipole, with north and south magnetic poles situated near the geographic poles that undergo intervallic reversals and excursions. The geomagnetic field changes from place to place, and on time scales ranging from seconds to decades to eons. These changes can influence health and protection, and economic well-being. The geomagnetic field, along with its related phenomena, can both aid and degrade navigation and surveying techniques; it can hamper geophysical exploration; it can disorder electric power utilities and pipeline operations; and it can persuade modern communications systems, spaceship, and more.
Other vital sources of the geomagnetic field contain electric current flowing in the ionized upper atmosphere and currents flowing within the earth’s crust. There are also local anomalies produced by mountain ranges, ore deposits, geological faults, and artificial products such as trains, aircraft, power lines etc.