A report on Geomagnetic reversal

Geomagnetic polarity during the last 5 million years (Pliocene and Quaternary, late Cenozoic Era). Dark areas denote periods where the polarity matches today's normal polarity; light areas denote periods where that polarity is reversed.
Geomagnetic polarity since the middle Jurassic. Dark areas denote periods where the polarity matches today's polarity, while light areas denote periods where that polarity is reversed. The Cretaceous Normal superchron is visible as the broad, uninterrupted black band near the middle of the image.
NASA computer simulation using the model of Glatzmaier and Roberts. The tubes represent magnetic field lines, blue when the field points towards the center and yellow when away. The rotation axis of the Earth is centered and vertical. The dense clusters of lines are within the Earth's core.

Change in a planet's magnetic field such that the positions of magnetic north and magnetic south are interchanged .

- Geomagnetic reversal
Geomagnetic polarity during the last 5 million years (Pliocene and Quaternary, late Cenozoic Era). Dark areas denote periods where the polarity matches today's normal polarity; light areas denote periods where that polarity is reversed.

22 related topics with Alpha

Overall

Computer simulation of Earth's field in a period of normal polarity between reversals. The lines represent magnetic field lines, blue when the field points towards the center and yellow when away. The rotation axis of Earth is centered and vertical. The dense clusters of lines are within Earth's core.

Earth's magnetic field

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Magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun.

Magnetic field that extends from Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun.

Computer simulation of Earth's field in a period of normal polarity between reversals. The lines represent magnetic field lines, blue when the field points towards the center and yellow when away. The rotation axis of Earth is centered and vertical. The dense clusters of lines are within Earth's core.
Common coordinate systems used for representing the Earth's magnetic field.
Relationship between Earth's poles. A1 and A2 are the geographic poles; B1 and B2 are the geomagnetic poles; C1 (south) and C2 (north) are the magnetic poles.
The movement of Earth's North Magnetic Pole across the Canadian arctic.
An artist's rendering of the structure of a magnetosphere. 1) Bow shock. 2) Magnetosheath. 3) Magnetopause. 4) Magnetosphere. 5) Northern tail lobe. 6) Southern tail lobe. 7) Plasmasphere.
Background: a set of traces from magnetic observatories showing a magnetic storm in 2000.
Globe: map showing locations of observatories and contour lines giving horizontal magnetic intensity in μ T.
Estimated declination contours by year, 1590 to 1990 (click to see variation).
Strength of the axial dipole component of Earth's magnetic field from 1600 to 2020.
Geomagnetic polarity during the late Cenozoic Era. Dark areas denote periods where the polarity matches today's polarity, light areas denote periods where that polarity is reversed.
Variations in virtual axial dipole moment since the last reversal.
A schematic illustrating the relationship between motion of conducting fluid, organized into rolls by the Coriolis force, and the magnetic field the motion generates.
A model of short-wavelength features of Earth's magnetic field, attributed to lithospheric anomalies
Example of a quadrupole field. This can also be constructed by moving two dipoles together.

However, at irregular intervals averaging several hundred thousand years, Earth's field reverses and the North and South Magnetic Poles respectively, abruptly switch places.

A photograph of Earth taken by the crew of Apollo 17 in 1972. A processed version became widely known as The Blue Marble.

Earth

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Third planet from the Sun and the only astronomical object known to harbor life.

Third planet from the Sun and the only astronomical object known to harbor life.

A photograph of Earth taken by the crew of Apollo 17 in 1972. A processed version became widely known as The Blue Marble.
Planetary disk of a star, the inner ring has a radius equal to Earth and the Sun
Artist's impression of earth during the Archean eon, showing falling meteor, erupting volcano, round stromatolites, and barren landscape
Earth topological map, the area is redder if it is raised higher in real-life
Global map of heat flow from Earth's interior to the surface
Earth's major plates, which are: · ·  ·  ·  ·
Satellite picture of Upsala Glacier, showing mountains, icebergs, lakes, and clouds
Schematic of Earth's magnetosphere, with the solar wind flows from left to right
Earth's rotation imaged by Deep Space Climate Observatory, showing axis tilt
Illustration of the Earth, Earth's orbit, the Sun and the four seasons
Earth's axial tilt and its relation to the rotation axis and planes of orbit
Earth-Moon system seen from Mars
A model of Vanguard 1, the oldest human-made object in Earth orbit
Water is transported to various parts of the hydrosphere via the water cycle
Top of Earth's blue-tinted atmosphere, with the Moon at the background
Fungi are one of the kingdoms of life on Earth.
The seven continents of Earth:
Earth's land use for human agriculture
Change in average surface air temperature since the industrial revolution, plus drivers for that change. Human activity has caused increased temperatures, with natural forces adding some variability.
Earthrise, taken in 1968 by William Anders, an astronaut on board Apollo 8
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Hubble Space Telescope seen in orbit from Space Shuttle Atlantis
Processes leading to movements and phase changes in Earth's water
Tracy Caldwell Dyson in the Cupola module of the International Space Station observing the Earth below

This causes secular variation of the main field and field reversals at irregular intervals averaging a few times every million years.

Simplified map of Earth's principal tectonic plates, which were mapped in the second half of the 20th century (red arrows indicate direction of movement at plate boundaries)

Plate tectonics

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Generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large tectonic plates which have been slowly moving since about 3.4 billion years ago.

Generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large tectonic plates which have been slowly moving since about 3.4 billion years ago.

Simplified map of Earth's principal tectonic plates, which were mapped in the second half of the 20th century (red arrows indicate direction of movement at plate boundaries)
Diagram of the internal layering of Earth showing the lithosphere above the asthenosphere (not to scale)
Divergent boundary
Convergent boundary
Transform boundary
Plate motion based on Global Positioning System (GPS) satellite data from NASA JPL. Each red dot is a measuring point and vectors show direction and magnitude of motion.
Detailed map showing the tectonic plates with their movement vectors.
Alfred Wegener in Greenland in the winter of 1912–13.
Global earthquake epicenters, 1963–1998. Most earthquakes occur in narrow belts that correspond to the locations of lithospheric plate boundaries.
Map of earthquakes in 2016
Seafloor magnetic striping.
A demonstration of magnetic striping. (The darker the color is, the closer it is to normal polarity)
Plate tectonics map

The second piece of evidence in support of continental drift came during the late 1950s and early 60s from data on the bathymetry of the deep ocean floors and the nature of the oceanic crust such as magnetic properties and, more generally, with the development of marine geology which gave evidence for the association of seafloor spreading along the mid-oceanic ridges and magnetic field reversals, published between 1959 and 1963 by Heezen, Dietz, Hess, Mason, Vine & Matthews, and Morley.

Brunhes–Matuyama reversal

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The Brunhes–Matuyama reversal, named after Bernard Brunhes and Motonori Matuyama, was a geologic event, approximately 781,000 years ago, when the Earth's magnetic field last underwent reversal.

Allan V. Cox

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American geophysicist.

American geophysicist.

His work on dating geomagnetic reversals, with Richard Doell and Brent Dalrymple, made a major contribution to the theory of plate tectonics.

Frederick Vine (right) and Drummond Matthews, 1981

Frederick Vine

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English marine geologist and geophysicist.

English marine geologist and geophysicist.

Frederick Vine (right) and Drummond Matthews, 1981
The observed magnetic profile for the sea floor around a mid-oceanic ridge agrees closely with the profile predicted by the Vine–Matthews–Morley hypothesis.

He made key contributions to the theory of plate tectonics, helping to show that the seafloor spreads from mid-ocean ridges with a symmetrical pattern of magnetic reversals in the basalt rocks on either side.

Richard Doell

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Richard Doell (1923 – March 6, 2008) was a distinguished American scientist known for developing the time scale for geomagnetic reversals with Allan V. Cox and Brent Dalrymple.

Professor Motonori Matuyama (right) and technical assistant Naoiti Kumagai (left) with Meinesz’s pendulum aboard submarine Ro 57 in 1934

Motonori Matuyama

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Professor Motonori Matuyama (right) and technical assistant Naoiti Kumagai (left) with Meinesz’s pendulum aboard submarine Ro 57 in 1934

Motonori Matuyama was a Japanese geophysicist who was (in the late 1920s) the first to provide systematic evidence that the Earth's magnetic field had been reversed in the early Pleistocene and to suggest that long periods existed in the past in which the polarity was reversed.

Abraham Ortelius by Peter Paul Rubens, 1633

Continental drift

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Hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed.

Hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed.

Abraham Ortelius by Peter Paul Rubens, 1633
Antonio Snider-Pellegrini's Illustration of the closed and opened Atlantic Ocean (1858)
Alfred Wegener
Fossil patterns across continents (Gondwanaland)
Mesosaurus skeleton, MacGregor, 1908

The new crust is magnetized by the earth's magnetic field, which undergoes occasional reversals.

Bernard Brunhes (1867–1910), French geophysicist who discovered the Earth's magnetic field reversals

Bernard Brunhes

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Bernard Brunhes (1867–1910), French geophysicist who discovered the Earth's magnetic field reversals

Antoine Joseph Bernard Brunhes (3 July 1867 – 10 May 1910) was a French geophysicist known for his pioneering work in paleomagnetism, in particular, his 1906 discovery of geomagnetic reversal.