The Earth beneath our feet is shifting in ways we’ve never seen before.
Giant droplets of the mantle are sinking as if lava is flowing backwards. This new phenomenon points to a changing planet, and we’re not sure what the implications are yet.
Cratons are supposed to be the unbreakable anchors of our planet, but new seismic data reveal that parts of North America are collapsing deep under the surface.
Why are Earth’s ancient foundations failing?
What happens when our “unshakeable” foundations start flinching
The continent of North America has been resting upon a solid foundation for billions of years.
This section of Earth is called a craton—a massive slab of ancient anchor rock that serves as a geological anchor.
While tectonic plates are known for their grinding volatility, triggering earthquakes or igniting volcanoes, cratons are defined by stability.
If “steady as a rock” needed illustration, cratons are it. So when they start rattling the foundations of an entire continent, geologists have to reevaluate their “immortality.”
Recent seismic imaging has revealed a crack in the foundations, and the center is no longer holding.
EarthScope project data points to a process of disintegration. A similar crumbling once took place in the North China Craton, but this ended millions of years ago.
The current discovery is unprecedented in that this loss of craton integrity is taking place in real-time.
While the continent is being compromised, our understanding of how Earth works is being challenged.
A subterranean Jurassic “ghost” from 200 million years ago may explain the future
Events 200 million years ago may offer insight into the “backwards-moving” lava.
In the time of the dinosaurs, the Farallon Plate oceanic slab started edging under North America’s western edge.
Although it headed deeper into the Earth, it didn’t vanish.
This sinking slab of rock mass has been shaping the North American landscape for eons. This is not news. But we never knew it would affect the continent beyond the mountain ranges and volcanic arcs of the West.
The latest tomographic models have exposed that the Farallon Plate has extended much further inland than imagined.
It has reached far beyond the stable Midwest. Now, it’s a massive, lurking obstruction deep in Earth’s exterior.
It is so active that a localized “weather system” of rock and heat has formed.
According to the Jackson School of Geosciences, the chemistry and temperature of the continental roots are being fundamentally altered.
The process is slow and erosive rather than a sudden collision. But geologists are nevertheless scrambling to make predictions of the whole of North America.
A continent in liquefaction: Are we ready to learn that North America isn’t immortal?
The explanation for North America’s weakening core is bizarre, but definitive: the continent is “dripping” into the Earth’s mantle.
Scientists used full-waveform tomographic modeling to observe the underside of the craton, and it wasn’t pretty. Parts of the slab are disintegrating in literal “blobs.”
The Farallon Plate is causing havoc under the surface
The deforming rock phenomenon has a term—lithospheric dripping—and it’s down to the mantle being redirected by the subductive Farallon Plate.
This redirected flow is essentially “wearing away” and thinning the base of the continent.
The release of volatile compounds from the sinking slab isn’t helping matters.
The Midwest’s foundation is now a series of sinking droplets rather than a solid, static anchor.
As the craton’s root is eroded by the mantle, heavy, weakened pieces are being sucked into the intense heat below.
Land-dwellers aren’t at risk, and the Midwest is not sinking into an abyss—yet. But this is the first live study of decratonization and geologists are thinking, what a time to be alive.
Does the realization that our “permanent” continent is being slowly recycled rattle your sense of stability?