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Textbook Case of Tectonic Movement is Wrong, Says New Study Results from an expedition to the sea floor near the Hawaiian Islands show evidence that the deep Earth is more unsettled than geologists have long believed. A new University of Rochester study suggests that the long chain of islands and seamounts, which is deemed a "textbook" example of tectonic plate motion, was formed in part by a moving plume of magma, upsetting the prevailing theory that plumes have been unmoving fixtures in Earth's history. The research will be published in the August 22 issue of Science. "Mobile magma plumes force...

The Earth’s continuously changing magnetic field surrounds the planet like an invisible force field – deflecting highly charged solar particles. Reversals are the rule, not the exception. Earth has settled in the last 20 million years into a pattern of a pole reversal about every 200,000 to 300,000 years, although it has been more than twice that long since the last reversal, the Brunhes-Matuyama, that occurred around 780,000 years ago. A temporary reversal, the Laschamp event, occurred around 41,000 years ago, and lasted less than 1,000 years with the actual change of polarity lasting around 250 years. Our planet’s history...

Earth’s magnetic field surrounds our planet like an invisible force field - protecting life from harmful solar radiation by deflecting charged particles away. Far from being constant, this field is continuously changing. Indeed, our planet's history includes at least several hundred global magnetic reversals, where north and south magnetic poles swap places. So when’s the next one happening and how will it affect life on Earth? During a reversal the magnetic field won’t be zero, but will assume a weaker and more complex form. It may fall to 10 percent of the present-day strength and have magnetic poles at the...

Anyone watching a compass needle point steadily north might suppose that Earth’s magnetic field is a constant. It’s not. Researchers have long known that changes are afoot. The north magnetic pole routinely moves, as much as 40 km/yr, causing compass needles to drift over time. Moreover, the global magnetic field has weakened 10% since the 19th century. Earth’s magnetic field protects us from solar storms and cosmic rays. Less magnetism means more radiation can penetrate our planet’s atmosphere. Indeed, high altitude balloons launched by Spaceweather.com routinely detect increasing levels of cosmic rays over California. Perhaps the ebbing magnetic field over...

Since 2010, the best estimate of the age of Earth's magnetic field has been 3.45 billion years. But now a researcher responsible for that finding has new data showing the magnetic field is far older. John Tarduno, a geophysicist at the University of Rochester and a leading expert on Earth's magnetic field, and his team of researchers say they believe the Earth's magnetic field is at least four billion years old.

NASA’s magnetic field mission looking for green energy In addition to learning more about the magnetic field of the Earth, and the ubiquitous but hard to understand “magnetic reconnection,” NASA’s new MMS mission is also looking for ways to harness the power of magnetism, and produce clean energy. NASA’s MMS mission will investigate magnetic reconnection.Findings from this mission could lead to production of green energy from magnetism.Magnetic reconnection is ubiquitous in the cosmos, but it’s still poorly understood. After years of intensive planning, with countless days of engineering works, data analysis, and more, the National Aeronautics and Space Administration on Thursday successfully launched the...

Technicians work on NASA’s 20-foot-tall Magnetospheric Multiscale (MMS) mated quartet of stacked observatories in the cleanroom at NASA's Goddard Space Flight Center in Greenbelt, Md., on May 12, 2014. Credit: Ken Kremer- kenkremer.com NASA’s first mission dedicated to study the process in nature known as magnetic reconnection undergoing final preparation for launch from Cape Canaveral, Florida in just under two weeks time. The Magnetospheric Multiscale (MMS) mission is comprised of a quartet of identically instrumented observatories aimed at providing the first three-dimensional views of a fundamental process in nature known as magnetic reconnection. Magnetic reconnection is the process whereby...

“A geomagnetic reversal may happen sooner than expected,” says this article in Scientific American.

The Earth's magnetic field experiences unpredictable, rapid, and intense anomalies that are known as geomagnetic jerks. Initially described in 1978, geomagnetic jerks are unpredictable events that abruptly accelerate the evolution of the Earth's magnetic field, and skew predictions of its behaviour on a multi-year scale. The Earth's magnetic field is produced by the circulation of matter within its metallic core, via the energy released when this core cools. Researchers know of two types of movements that cause two types of variations in the magnetic field: those resulting from slow convection movement, which can be measured on the scale of a...

The northern lights (above) and their lesser-known sibling the southern lights, aurora borealis and aurora australis, respectively, undulate across the skies in hazy green and sometimes red ribbons near Earth’s polar regions. The two phenomena aren’t identical, however, and now researchers think they know why. Aurorae appear as solar wind, a gust of charged particles emitted by the sun, blows across Earth’s magnetic field. Because the charged particles flow along symmetrical lines in Earth’s magnetic field linking the north and south poles, it made sense to assume the atmospheric displays in each hemisphere would mirror each other. Advances in Earth...

Earth’s magnetic field is what allows us to exist. It deflects harmful radiation. It keeps our water and atmosphere in place. But now it’s acting up — and nobody knows why. Planet Earth is alive. Deep beneath its skin, its life blood — rivers of molten iron — pulse around its core. And this mobile iron is what generates the magnetic field that causes auroras — and keeps us alive. But, according to the science journal Nature, something strange is going on deep down below. It’s causing the magnetic North Pole to ‘skitter’ away from Canada, towards Siberia. “The magnetic...

Rapid shifts in the Earth’s north magnetic pole are forcing researchers to make an unprecedented early update to a model that helps navigation by ships, planes and submarines in the Arctic, scientists said.

'Hot spots' of plume from deep Earth could propel plate motions around globeBringing fresh insight into long-standing debates about how powerful geological forces shape the planet, from earthquake ruptures to mountain formations, scientists at Scripps Institution of Oceanography at UC San Diego have identified a new mechanism driving Earth's massive tectonic plates. Scientists who study tectonic motions have known for decades that the ongoing "pull" and "push" movements of the plates are responsible for sculpting continental features around the planet. Volcanoes, for example, are generally located at areas where plates are moving apart or coming together. Scripps scientists Steve Cande...

IT'S crawling with life down there. A remote expedition to the deepest layer of the Earth's oceanic crust has revealed a new ecosystem living over a kilometre beneath our feet. It is the first time that life has been found in the crust's deepest layer, and an analysis of the new biosphere suggests life could exist lower still. On a hypothetical journey to the centre of the Earth starting at the sea floor, you would travel through sediment, a layer of basalt, and then hit the gabbroic layer, which lies directly above the mantle. Drilling expeditions have reached this layer...

Researchers at Monash University and Scripps Institution of Oceanography identify movements of plate and plate boundaries; could substantially improve models of tectonic motionScripps Institution of Oceanography / University of California, San DiegoA team of researchers including Scripps Institution of Oceanography, UC San Diego geophysicist Dave Stegman has developed a new theory to explain the global motions of tectonic plates on the earth's surface. The new theory extends the theory of plate tectonics - a kinematic description of plate motion without reference to the forces behind it - with a dynamical theory that provides a physical explanation for both the motions...

The ancient sea floor was discovered in southwest Greenland A sliver of four-billion-year-old sea floor has offered a glimpse into the inner workings of an adolescent Earth.The baked and twisted rocks, now part of Greenland, show the earliest evidence of plate tectonics, colossal movements of the planet's outer shell. Until now, researchers were unable to say when the process, which explains how oceans and continents form, began. The unique find, described in the journal Science, shows the movements started soon after the planet formed. "Since the plate tectonic paradigm is the framework in which we interpret all modern-day geology,...

Russell Mapes, a graduate student from Grass Valley, Calif., ...explains that these sediments of eastern origin were washed down from a highland area that formed in the Cretaceous Period, between 65 million and 145 million years ago, when the South American and African tectonic plates separated and passed each other. That highland tilted the river's flow westward, sending sediment as old as 2 billion years toward the center of the continent. A relatively low ridge, called the Purus Arch, which still exists, rose in the middle of the continent, running north and south, dividing the Amazon's flow - eastward toward...

Ice Ages Blamed on Tilted Earth By Michael Schirber LiveScience Staff Writer posted: 30 March 2005 In the past million years, the Earth experienced a major ice age about every 100,000 years. Scientists have several theories to explain this glacial cycle, but new research suggests the primary driving force is all in how the planet leans. The Earth’s rotation axis is not perpendicular to the plane in which it orbits the Sun. It's offset by 23.5 degrees. This tilt, or obliquity, explains why we have seasons and why places above the Arctic Circle have 24-hour darkness in winter and constant...

The magnetic pole is moving so quickly that it has forced the world’s geomagnetism experts into a rare move. On 15 January, they are set to update the World Magnetic Model, which describes the planet’s magnetic field and underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones. The most recent version of the model came out in 2015 and was supposed to last until 2020 — but the magnetic field is changing so rapidly that researchers have to fix the model now. The problem lies partly with the moving pole and partly...

Like any spinning object, Earth is subject to centrifugal force, which tugs on the planet's fluid interior. At the equator, where this force is strongest, Earth is more than 26 miles larger in diameter than at the poles. Gordon said true polar wander may occur when dense, highly viscous bumps of mantle build up at latitudes away from the equator. If the mantle anomalies are massive enough, they can unbalance the planet, and the equator will gradually shift to bring the excess mass closer to the equator. The planet still spins once every 24 hours and true polar wander does...