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https://theconversation.com/the-biggest-ever-sample-of-core-material-from-earths-mantle-could-have-valuable-clues-into-the-origins-of-life-236562>
"If you were to slice through it, you would see the Earth is divided into
distinct layers. On top is the relatively thin crust where we live. Beneath
that is the 2,900 km thick mantle layer. Then, enclosed within the mantle is
the innermost metallic core of our planet.
The mantle is Earth’s largest layer of rocks. However, because it is covered by
at least six kilometres of crust, drilling into it has not generally been
possible. The only exception has been where the mantle is exposed by faulting,
where a crack forms in the Earth’s crust.
I was part of an international team which retrieved a record-breaking
1,268m-long drill core (a long cylindrical sample of rock collected by the
drill) of mantle rock from the seabed. This sample, which is more than six
times longer than the previous core of mantle rock, has given us a glimpse into
the composition of this mostly inaccessible layer of the Earth. You can read
full details in the journal
Science.
The types of rock we retrieved are known as abyssal peridotites – the primary
rocks of Earth’s upper mantle. We collected the core from a zone called the
Mid-Atlantic Ridge on the seafloor under the North Atlantic Ocean. The drill
was deployed from the research ship
Joides Resolution. This happened on
Expedition 399 of a project called the IODP (International Ocean Discovery
Program).
As well as offering new insights into mantle composition, the drill core gives
us other glimpses into Earth’s deep geology and the conditions that could have
been involved in the origins of life."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
