Thursday , April 22 2021

Diamond defects reveal the secrets of the formation of continents on Earth



Diamond gaps can make it less valuable for jewelry collections or newly-born women, but for scientists, these minor defects only make them more precious.
From diamonds
are formed deep in the planet of the Earth, small grains of minerals are trapped in these beautiful rocks. These are considered imperfections in jewelry trade, but scientists analyze these imperfections to learn about environmental conditions when forming the rock.
"We found a way to use the traces of sulfur from ancient volcanoes that penetrated the mantle and eventually are in diamonds to provide evidence of a particular process of building the continent," said
Karen Smith, of the American Institute of Genomics and lead author of the study, in a Carnegie Science report.
Mantya Kiels
Beneath the surface of the Earth, about 93 to 124 miles (150 to 200 kilometers), there are formations known as mantle keels that stabilize the continental crust
. For these buoyant vessels for the preservation of the land, even in conditions of destructive tectonic activities on the planet, the material constituting these mantle cells should be thickened, stabilized and cooled just below the continent.
The question is: how? Scientists debate the answer, with some suggestive mantle carvings being produced by subduction, which is when a tectonic plate slides below another and sinks into the depths of the ocean. On the other hand, others theorize that they form through a warm magma rising from deep into the planet.
The extraction of the mantle shape is an important part of the merging of continent history and learning about their continued survival, according to co-author Steve Shiri of Carnegie.
"Since this is the only tectonically active, rocky planet we know, understanding of geology for the formation of our continents is an essential part of the discernment that makes the Earth suitable," added Shiri.
Diamonds are the best friend of the geologist
Fortunately, diamonds can help answer this question because these sparkling rocks are formed within these coats. By studying the mineral grains embedded in diamonds – known as imperfections or inclusions – scientists can discover the nature and origin of the mantle cells from where the diamond comes from.
For the study published
in the journal "Science"
, scientists analyzed minerals rich in sulfur incorporated in diamonds from Sierra Leone and found that there were two subduction events in the region's history.
The researchers reached this conclusion because the chemistry of diamond minerals was last seen on the surface of the Earth
more than 2.5 billion years ago, before oxygen even became abundant in the atmosphere. Thus, the mineral in the mineral substrates had to be found on the surface in the past, and then penetrated the mantle with the process of subduction.
Diamonds in Botswana showed similar evidence, but diamonds from northern Canada were not. The researchers suggest that small knives in the second region can be formed with a different process that does not include surface material.
"Our work shows that sulphide inclusions in diamonds are a powerful tool for exploring the processes of building the continent," said Smith.


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