A team of Harvard scientists may have found an
indication that a portion of an ancient Earth exists inside our planet’s
mantle.
A study presented at the Goldschmidt conference in
Sacramento, California, claims that the previously inexplicable isotope ratio
from the depths of the Earth may be an “echo” of the ancient Earth that
existed before the collision with another celestial body, which is
estimated to have led to the formation of the Moon 4.5 billion years ago.
According to the authors of the study, the
ratio may represent a signal from a material that existed prior to the moment
of the collision.
Scientists of the Harvard University led by
Associate Professor Sujoy Mukhopadhyay believe that only a portion of
the Earth melted as a result of the collision, and that in the depths of our
planet’s mantle there still exists a part of the ancient Earth.
Scientists have studied the isotope ratio
of noble gases from the depths of the Earth’s mantle and compared it to the
isotope ratio of the gases found closer to the surface. They found that the
ratio of 3He to 22Ne from the surface layers of the mantle is much higher than
the one of its deeper layers.
The analysis of the 129-Xenon and 130-Xenon
ratio also confirms the hypothesis suggested by the researchers. Material
which has been rendered to the surface from the deep mantle has a lower ratio
than the one which is typically located near the surface.
Since the 129-Xenon is produced by the
radioactive decay of 129-Iodine, these isotopes indicate that the ancient
part of mantle was formed during the first 100 million years of the Earth’s
evolution.
Scientists believe that this theory
explains the differences between the isotope ratios of noble gases in different
parts of the Earth.
As Professor Mukhopadhyay said: “The
geochemistry indicates that there are differences between the noble gas isotope
ratios in different parts of the Earth, and these need to be explained. The
idea that a very disruptive collision of the Earth with another planet-sized
body, the biggest event in Earth’s geological history, did not completely melt
and homogenize the Earth challenges some of our notions on planet formation and
the energetics of giant impacts. If the theory is proven correct, then we may
be seeing echoes of the ancient Earth, from a time before the collision“.
ABOUT THE AUTHOR
Anna LeMind is the owner and
lead editor of the website Learning-mind.com, and a staff writer
for The
Mind Unleashed.
Featured image: (Pictured
above: An ancient impact crater, via Wikimedia Commons
You worded this in a way that is going to make those "Earth inside the Earth" people freak out and think they are right; when it's not.
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