At the bottom of the Earth’s mantle are two large formations formed by unusual rocks, which are referred to as Large Low Shear Velocity Provinces (LLSVP). Seismic waves travel through them much more slowly than other parts of the mantle and are areas larger than the size of entire continents, which can measure up to 1000 km vertically.
–
The new study claims that the LLSVP are the remnants of a collision with the planet Theia, thanks to which we are supposed to have the Moon today, which is a very ancient clash of young Earth about 4.5 billion years ago. This is claimed by geodynamicist Qian Yuan, a doctoral student at Arizona State University (ASU) he presented the hypothesis na Lunar and Planetary Science Conference.-
According to the hypothesis, LLSVP structures could be created by collision with Theia if its mantle were made of a material with a density only 1.5 to 3.5% higher than the Earth’s mantle. This would cause part of Theiye’s original mantle to never fully mix with the Earth’s mantle, in which case our mantle would now be up to 15 percent Theia, and the resulting LLSVP of the “unmixed” Theiy mantle could take up 3 to 9 percent of the volume. Earth’s mantle.
LLSVP at the bottom of the Earth’s mantle-
Of course, there are other explanations for these formations, such as simply the penetration of material from the outer core into the mantle or, conversely, the ancient remains of the oceanic crust, which gradually sank to the bottom of the mantle.
But now, too, we may not speak only of the four main layers of the Earth, that is, the crust, the mantle (sometimes divided into upper and lower), the outer and inner core. There may be a new fifth layer.
–
Now it seems that the scientists’ assumptions have been confirmed, and that we will have to divide the inner core into two layers, which are divided at a depth of about 5800 km below the surface, or about 700 kilometers below the border where the inner core begins. This is a fundamental change in the structure of the solid inner core, which, unlike the outer, is not liquid, due to the action of high pressure.
Scientists used an algorithm here, which compared thousands of different models of the Earth’s internal composition with decades of recordings of long seismic waves propagating across the planet. This corresponds to the presence of another layer, which further divides the inner core. –
Prices of related products:
–
