Mantle Rock Behind Yellowstone’s Supereruptions Extends To Northern California

Victor Camp has spent a lifetime studying volcanic eruptions all over the world, starting in Saudi Arabia, then Iran, and eventually the Pacific Northwest. The geology lecturer finds mantle plumes that feed the largest of these eruptions fascinating, because of their massive size and the impact they can have on our environment.

Over the past two years, this abiding interest helped him connect the dots and discover that the mantle source rock that rises upward from beneath Yellowstone National Park to feed its periodic supereruptions also spreads out west all the way to Northern California and Oregon.

On its westward journey, it acts as the catalyst for fairly young—meaning less than 2 million years old—volcanic eruptions at places such as Craters of the Moon National Monument and Preserve in Idaho, before reaching Medicine Lake Volcano in the northeastern tip of California, close to the Oregon border.

The mantle rock spreads laterally through narrow flow-line channels well below the earth’s crust for over 500 miles, bifurcating twice: once as it leaves Yellowstone and again as it reaches the California-Oregon border. These lines end at Medicine Lake, an active volcano near Mount Shasta, and at Newberry Volcano, an active volcano about 20 miles south of Bend, Ore.

This discovery is significant because it reveals how mantle plumes similar to the one beneath Yellowstone behave as they feed the majority of the world’s largest volcanic eruptions of basaltic lava, including the ones in Hawaii.

“Since the plume is not controlled by plate tectonics, it can rise and emerge anywhere on earth, depending on where it manages to break through the earth’s surface,” Camp said. “So, knowing this will help us understand supereruptions that have occurred before, and those that will occur in the future.”

The results of his self-funded study were published in the journal Geology in May.

Mantle plumes are composed of very hot, low-density mantle rock. Mantle is one of three major layers of planet earth—we live on the earth’s crust, the thinnest layer, and mantle is the second denser layer that extends from about 100 kilometers (62 miles) below the earth’s surface all the way down to about 2,700 kilometers (about 1,680 miles), and further down is the core of the earth comprised mostly of iron mixed with a few other elements.

Mantle plumes are technically mantle rock, but because they are hotter and more buoyant than surrounding mantle they rise in a plume-like form. When the Yellowstone plume first reached the base level of the North American tectonic plate, it was blocked by the rigidity of the cold plate base which acted as a barrier. At this depth of about 100 kilometers, the plume began to decompress and melt, while simultaneously spreading laterally to the west.

The mantle rock that Camp traced to California took many millions of years to move out west. What’s interesting is that the source of the mantle rock under Yellowstone today originated at the core-mantle boundary geographically centered near present-day San Diego, but very deep beneath the earth’s surface we reside on—and took a circuitous route through different regions of the mantle before it rose up underneath the Yellowstone volcano.

Camp sourced seismic tomography images, similar to X-rays and CT-scans (computerized tomography scans), that show how the mantle plume ascended, and he analyzed field data as well as published chemistry and age data on volcanic rocks at the surface, to demonstrate its westward flow.

Earth’s Last Magnetic Field Reversal Took Far Longer Than Once Thought

Earth’s magnetic field seems steady and true—reliable enough to navigate by.

Yet, largely hidden from daily life, the field drifts, waxes and wanes. The magnetic North Pole is currently careening toward Siberia, which recently forced the Global Positioning System that underlies modern navigation to update its software sooner than expected to account for the shift.

And every several hundred thousand years or so, the magnetic field dramatically shifts and reverses its polarity: Magnetic north shifts to the geographic South Pole and, eventually, back again. This reversal has happened countless times over the Earth’s history, but scientists have only a limited understanding of why the field reverses and how it happens.

New work from University of Wisconsin-Madison geologist Brad Singer and his colleagues finds that the most recent field reversal, some 770,000 years ago, took at least 22,000 years to complete. That’s several times longer than previously thought, and the results further call into question controversial findings that some reversals could occur within a human lifetime.

The new analysis—based on advances in measurement capabilities and a global survey of lava flows, ocean sediments and Antarctic ice cores—provides a detailed look at a turbulent time for Earth’s magnetic field. Over millennia, the field weakened, partially shifted, stabilized again and then finally reversed for good to the orientation we know today.

The results provide a clearer and more nuanced picture of reversals at a time when some scientists believe we may be experiencing the early stages of a reversal as the field weakens and moves. Other researchers dispute the notion of a present-day reversal, which would likely affect our heavily electronic world in unusual ways.

Singer published his work Aug. 7 in the journal Science Advances. He collaborated with researchers at Kumamoto University in Japan and the University of California, Santa Cruz.

“Reversals are generated in the deepest parts of the Earth’s interior, but the effects manifest themselves all the way through the Earth and especially at the Earth’s surface and in the atmosphere,” explains Singer. “Unless you have a complete, accurate and high-resolution record of what a field reversal really is like at the surface of the Earth, it’s difficult to even discuss what the mechanics of generating a reversal are.”

Earth’s magnetic field is produced by the planet’s liquid iron outer core as it spins around the solid inner core. This dynamo action creates a field that is most stable going through roughly the geographic North and South poles, but the field shifts and weakens significantly during reversals.

As new rocks form—typically either as volcanic lava flows or sediments being deposited on the sea floor—they record the magnetic field at the time they were created. Geologists like Singer can survey this global record to piece together the history of magnetic fields going back millions of years. The record is clearest for the most recent reversal, named Matuyama-Brunhes after the researchers who first described reversals.

For the current analysis, Singer and his team focused on lava flows from Chile, Tahiti, Hawaii, the Caribbean and the Canary Islands. The team collected samples from these lava flows over several field seasons.

“Lava flows are ideal recorders of the magnetic field. They have a lot of iron-bearing minerals, and when they cool, they lock in the direction of the field,” says Singer. “But it’s a spotty record. No volcanoes are erupting continuously. So we’re relying on careful field work to identify the right records.”

The researchers combined magnetic readings and radioisotope dating of samples from seven lava flow sequences to recreate the magnetic field over a span of about 70,000 years centered on the Matuyama-Brunhes reversal. They relied on upgraded methods developed in Singer’s WiscAr geochronology lab to more accurately date the lava flows by measuring the argon produced from radioactive decay of potassium in the rocks.

They found that the final reversal was quick by geological standards, less than 4,000 years. But it was preceded by an extended period of instability that included two excursions—temporary, partial reversals—stretching back another 18,000 years. That span is more than twice as long as suggested by recent proposals that all reversals wrap up within 9,000 years.

The lava flow data was corroborated by magnetic readings from the seafloor, which provides a more continuous but less precise source of data than lava rocks. The researchers also used Antarctic ice cores to track the deposition of beryllium, which is produced by cosmic radiation colliding with the atmosphere. When the magnetic field is reversing, it weakens and allows more radiation to strike the atmosphere, producing more beryllium.

Since humanity began recording the strength of the magnetic field, it has decreased in strength about five percent each century. As records like Singer’s show, a weakening field seems to be a precursor to an eventual reversal, although it’s far from clear that a reversal is imminent.

A reversing field might significantly affect navigation and satellite and terrestrial communication. But the current study suggests that society would have generations to adapt to a lengthy period of magnetic instability.

“I’ve been working on this problem for 25 years,” says Singer, who stumbled into paleomagnetism when he realized the volcanoes he was studying served as a good record of Earth’s magnetic fields. “And now we have a richer record and better-dated record of this last reversal than ever before.”

Drop Of Ancient Seawater Rewrites Earth’s History

The remains of a microscopic drop of ancient seawater has assisted in rewriting the history of Earth’s evolution when it was used to re-establish the time that plate tectonics started on the planet.

Plate tectonics is Earth’s vital — and unique — continuous recycling process that directly or indirectly controls almost every function of the planet, including atmospheric conditions, mountain building (forming of continents), natural hazards such as volcanoes and earthquakes, formation of mineral deposits and the maintenance of our oceans. It is the process where the large continental plates of the planet continuously move, and the top layers of the Earth (crust) are recycled into the mantle and replaced by new layers through processes such as volcanic activity.

Where it was previously thought that plate tectonics started about 2.7 billion years ago, a team of international scientists used the microscopic leftovers of a drop of water that was transported into the Earth’s deep mantle — through plate tectonics — to show that this process started 600 million years before that. An article on their research that proves plate tectonics started on Earth 3.3 billion years ago was published in the high impact academic journal, Nature, on 16 July.

“Plate tectonics constantly recycles the planet’s matter, and without it the planet would look like Mars,” says Professor Allan Wilson from the Wits School of Geosciences, who was part of the research team.

“Our research showing that plate tectonics started 3.3 billion years ago now coincides with the period that life started on Earth. It tells us where the planet came from and how it evolved.”

Earth is the only planet in our solar system that is shaped by plate tectonics and without it the planet would be uninhabitable.

For their research, the team analysed a piece of rock melt, called komatiite — named after the type occurrence in the Komati river near Barberton in Mpumalanga — that are the leftovers from the hottest magma ever produced in the first quarter of Earth’s existence (the Archaean). While most of the komatiites were obscured by later alteration and exposure to the atmosphere, small droplets of the molten rock were preserved in a mineral called olivine. This allowed the team to study a perfectly preserved piece of ancient lava.

“We examined a piece of melt that was 10 microns (0.01mm) in diameter, and analysed its chemical indicators such as H2O content, chlorine and deuterium/hydrogen ratio, and found that Earth’s recycling process started about 600 million years earlier than originally thought,” says Wilson. “We found that seawater was transported deep into the mantle and then re-emerged through volcanic plumes from the core-mantle boundary.”

The research allows insight into the first stages of plate tectonics and the start of stable continental crust.

“What is exciting is that this discovery comes at the 50th anniversary of the discovery of komatiites in the Barberton Mountain Land by Wits Professors, the brothers Morris and Richard Viljoen,” says Wilson.

FOLLOW UP: Probability of Earth Changing Events Within 14 Day

Historical evidence indicates large significant Earth changing events related to a Full Solar Eclipse. A pattern of events falls within a 28 day ‘window’ – as in window of opportunity. My research exhibits a cluster of natural phenomena had historically occurred 14 days prior to an eclipse – or within 14 days after.

The reason for large events to occur prior to a solar eclipse is not yet fully known. I speculate it is related to celestial alignments whereas charged particles and electromagnetic plasma interacts with our Sun and planetary orbs, one of which is Earth.

Close to and during a full solar eclipse, it is the sudden temperature fluctuation which can cause a chain reaction. Producing a sudden and rapid shift in both the jet stream and ocean currents, can cause the destabilization of set seasonal patterns. Additionally, what is often referred to as Extreme Weather involving tornadoes, hurricanes, straight line winds, and wind shears is almost always related to shifting ocean and jet stream

Although temperature flux may be subtle, if tectonics are at their tipping point, it would not take much to set them off. Additionally, the rapid yet subtle temperature change can cause the expansion and contraction of Earth’s lithosphere, which could set off a chain reaction of tectonic slippage resulting in significant earthquakes and volcanic eruptions.

Remember, the majority of volcanoes are submarine (ocean bottom); hence the rapid shift in ocean temperatures is also prone to set off a rippling effect which is often unpredictable due to the spider webbing tentacles which connect a system of mantle plumes and volcanoes.

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Science Of Cycles keeps you tuned-in and knowledgeable of what we are discovering, and how some of these changes will affect our communities and ways of living.

 

UPDATE: 2019 Full Solar Eclipse and Earth Changing Events

I have highlighted areas of concern as related to the causal effects of a total solar eclipse (shown below). If tectonics are at their tipping point, it would not take much to set them off. As mentioned, it is mostly the rapid temperature change which causes an expansion and contraction of Earth’s lithosphere, even if ever so slight.

Most ‘mantle plumes’ as well as volcanoes are sub-marine (ocean bottom); hence the rapid shift in ocean temperatures is also prone to set off a rippling effect which is often unpredictable due to the spider webbing tentacles which connect a system of mantle plumes and volcanoes.

A mantle plume is a large column of hot rock (magma) mostly originating from Earth’s core-mantle boundary. This flow of viscous material rises through the mantle, asthenosphere, and lithosphere finding its way to Earth’s surface or crust. The expanding or contracting movement of these events are the cause of earthquakes and volcanoes. The surface includes ocean bottoms causing an increase of ocean temperatures, which in-turn destabilizes the lower atmosphere contributing to forming or escalating tropical storms or hurricanes.

Next article will address perhaps a less scientific direction which suggest the current mode of global political dysfunction, may have some roots in history showing a pattern of “what happens below – reflects what happens above”. This suggest the turmoil which results from earth changing events appears to be in-sync with emotional unrest. Continued scientific data will of course follow.

Watch for ongoing reports as information comes in. I also plan to present a more extensive outline to the science behind my research, especially for those who may be new to my work.

Part – IX  The Mysterious South Atlantic Anomaly

What could be described as the epicenter of Earth’s weakening magnetic field, is known as the South Atlantic Anomaly (SAA). The region of the SAA is the result of a decaying dipole geomagnetic field which is now so pronounced that it allows the close approach of Earth’s radiation streams known as the Van Allen belt. The magnetic field strength is so weak in this region it is a hazard for airplanes and satellites to fly or orbit near this sector because the high cosmic radiation in this area can destroy electronic and human cells.

Earth’s magnetic field is created by convecting iron in our planet’s liquid inner core. In the SAA zone where Earth’s liquid inner core meets the more viscous outer core, the polarity of the field is opposite to the average global magnetic field. If we were able to use a compass deep under southern Africa, we would see that the magnetic field has already reversed – when facing north our compass would be pointing south.

In archaeo-magnetic studies we find geophysicists have teamed up with archaeologists, to learn about the past magnetic field. Clay used to make pottery contains small amounts of magnetic minerals, such as magnetite. Regarding the Southern Hemisphere, data was collected from ancestral tribes in southern Africa which had lived in huts built of clay. Just as in the case of the firing and cooling of pottery, the clay in these structures recorded Earth’s magnetic field as they cooled.

Over the last decade, researchers have accumulated images from the analyses of earthquakes seismic waves. As seismic shear waves move through the Earth’s layers, the speed with which they travel is an indication of the density of the layer. Now we know that a large area of slow seismic shear waves characterizes the core mantle boundary beneath southern Africa. It is known that regions of reversed flux at the core-mantle boundary have grown over time. New studies suggest the area known as the South Atlantic Anomaly, may be primarily responsible for the decay in the main dipolar field. This reverse patch is also responsible for the minimum in field strength now centered over South America.

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Science Of Cycles keeps you tuned-in and knowledgeable of what we are discovering, and how some of these changes will affect our communities and ways of living.

 

Part-VIII Just Where Are We in this Cycle of Magnetic Reversal?

Here we are now, in Part VIII of this series, and I would think a great question to ask would be “Where in this layered multitude of decadal, centennial, and millennial magnetic reversal cycles are we?” Current studies suggest we are further along the process indicating we could be just several decades, or perhaps a century or two away from a full magnetic reversal. Like all historic magnetic reversals, the process takes a few thousand years to develop. With each passing decade from the previous cycle, the intensity of charged particles increase as the Earth’s magnetic field decreases.

My research suggest the current influx of cosmic rays has increased over the last few decades, with noticeable increase over the last two years. Data from the Swarm satellite have shown the magnetic field is starting to weaken faster than in the past. Previously, researchers estimated the field was weakening about 5 percent per century, but the new data revealed the field is actually weakening at 5 percent per decade, or 10 times faster than thought. As such, rather than the full flip occurring in about 2,000 years, as was predicted, the new data suggest it could happen much sooner.

Historically, during extended solar minimum cycles which could range from 40,000 years to 700,000 years – each being its own cycle within a cycle, could be a contributing factor in historic global extinctions. I would ascertain and with using minimal consideration, you might have surmised a large part of my research is the study of cycles, hence, my company’s title Science Of Cycles.

Ѡ We have reached the halfway point for this project thanks to you. Now just short $500, perhaps there are five member supporters who could help out. But of course whatever each of you can contribute is welcome. btw, this multi-part series has taken notice by a few in our highly recognized scientific bodies.  CLICK HERE

An instinctive second and third question you might inquire would be: “What do we look for and what actually happens related to a magnetic shift?” I would suggest that perhaps within the next 20-30 years, there will be people alive today who will witness the process of magnetic north bouncing around the northern hemisphere above 60° latitude and swing between 30° east and 30° west longitudes. Furthermore, there will be some of you who are young enough to witness a more pronounced swing in both latitude and longitude as magnetic north will drop below the equator then bounce back within the next 50-60 years.

For a full polarity reversal to occur, the magnetic field needs to weaken by about 90% to a threshold level. This process can take thousands of years, and during this time, the lack of a protective magnetic shield around our planet allows more cosmic rays – high-energy particles mostly from within our galaxy Milky Way, but also from neighboring galaxies, will be able to penetrate our solar system and Earth. When this happens, these cosmic rays collide with more and more atoms in our atmosphere, such as nitrogen and oxygen. This produces variants of elements called cosmogenic isotopes, such as carbon-14 and beryllium-10, which fall to the surface. This provides a method of tracking reversals of the past, which helps assess future events.

Part – IX  The Mysterious South Atlantic Anomaly