Lasciate ogni speranza, voi ch’entrate – written on the gates of hell. “Leave the hope of everyone coming in here.” A great way to greet the visitor to hell. But there is also a real underground world, in which, however, fewer dogs and sinners in boilers are not cooked anywhere. Scientists thoroughly worked on a complete map of the dungeon. You can call her a card of hell, in some way.
Scientists have created an ‘Atlas of the Underworld,’ compiling the remnants of 94 ancient tectonic plates that now lie deep beneath Earth’s surface.
The atlas spans roughly 300 million years of Earth’s history, revealing how different geological processes changed the face of our planet.
Some of these slabs have sunk more than a thousand miles into the mantle, according to the researchers, giving rise to some of Earth’s most extraordinary features, from the Himalayas to the Pacific ‘Ring of Fire.’
The incredible catalog of the ‘underworld’ is 17 years in the making, according to Ars Technica.
Dutch scientists Douwe van der Meer, Douwe van Hinsbergen, and Wim Spakman of Utrecht University published their work in the journal Tectonophysics this month, interpreting 94 distinct slabs.
And, they’ve already identified two more.
The ‘slabs’ represent ancient tectonic plates that have sunk below the surface.
With recent seismic tomography techniques, researchers are now able to create 3D images of the hidden processes at work deep underground, revealing slabs as far as 2,900 kilometers (1801 miles) deep.
‘At subduction zone plate boundaries, one plate disappears below another and sinks into the mantle,’ the authors explain on the website dedicated to their work.
‘These sinking plates, called “slabs,” are colder than their surroundings, and remain colder for a very long period of time – about 250 million years.
‘As a result, the speed at which seismic waves travel through these bodies of sinking lithosphere is a little higher than from the surrounding hot mantle.’
Once these plates have descended to the mantle, they can remain there millions of years.
But, they do not stop moving.
WHAT ARE TECTONIC PLATES?
The Earth has fifteen tectonic plates (pictured) that together have molded the shape of the landscape we see around us today
Earthquakes typically occur at the boundaries of tectonic plates, where one plate dips below another, thrusts another upward, or where plate edges scrape alongside each other.
Earthquakes rarely occur in the middle of plates, but they can happen when ancient faults or rifts far below the surface reactivate.
These areas are relatively weak compared to the surrounding plate, and can easily slip and cause an earthquake.
While these plates may slow down, the researchers note that they eventually make their way from the upper mantle to the core-mantle boundary.
In creating the Atlas, the researchers have interpreted when and where the many slabs in Earth’s upper and lower mantle were sub-ducting.
The work not only sheds light on the activity beneath the surface, but could also improve our understanding of ancient climates and the activity of mantle hot spots.
As Earth’s geological activity is under constant study, the researchers expect there will be many improvements to their interpretations.
Already, they’ve identified more slabs than detailed in the paper.
‘We have found two more in the eastern Mediterranean region,’ van Hinsbergen told Ars Technica.
‘In Southeastern Australasia, in the deeper lower mantle, we do see more slabs; however, there isn’t sufficient geological literature available to date these.’
Source:
