Примери за използване на Lower mantle на Английски и техните преводи на Български
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The lower mantle is much more active than previously expected.
The mantle consists of the upper mantle, and the lower mantle.
We simulated the lower mantle. 100 gigapascals at 3,000 degrees.
The researchers started their research in the topmost part of the lower mantle.
The results of the UCL-Lisbon study indicated that the lower mantle displayed considerable activity in subduction zones.
In Science reveals mineral inclusions that originated in oceanic crust subducted into the lower mantle.
It's unclear whether the upper and lower mantle are mixed or remain independent of each other, each with its own chemical makeup.
The researchers mapped the responses to determine the structure andproperties of the various parts of the lower mantle.
The lower mantle moves and distorts at subduction zones, geologic areas where large pieces of oceanic crust sink through the layers.
In his lab at the Bayerisches Geoinstitut in Germany, Dan Frost is trying to simulate conditions found in the Earth's lower mantle.
Most experts believe that the lower mantle is dormant, but a recent European study found greater signs of dynamic activity in the region.
There is debate as to whether the rest of the mantle, especially the lower mantle, has the same bulk composition.
The researchers suggest these diamonds crystallized when diamond-forming fluids that originated in basalt from ocean crust subducted into the lower mantle.
Scientists have estimated that silicate perovskites constitute as much as 93% of Earth's lower mantle, but CaSiO3 had remained hypothetical up until this point.
The clincher is that as the inclusion was trapped in the diamond the whole time,the water signature can only have come from the diamond's place of formation in the lower mantle.
So far, the UCL-Lisbon researchers recognized signs of dislocation creep taking place in the lower mantle beneath South America and the Western Pacific.
For their lab experiments, the researchers made synthetic versions of ringwoodite from the transition zone as well as bridgmanite,which dominates the lower mantle.
Also with the models for the heat transport from the core to the lower mantle the new value agrees well and therefore provides a good basis for further investigations.
This much is evident: The blobs begin thousands of miles below Earth's surface,where the planet's rocky lower mantle meets the molten outer core.
Some geochemical andmineralogical evidence suggests that the upper and lower mantle are chemically different, which supports the idea that the two sections don't mix thermally or physically.
The smoother areas of the 660-km boundary could result from more thorough vertical mixing, while the rougher,mountainous areas may have formed where the upper and lower mantle don't mix as well.
The hotspots of liquid occur in the relatively thin boundary region between the solid lower mantle and the liquid outer core of the Earth where the temperature rises over a distance of just 200 kilometres from 3000 to 4000 degrees.
That's the conclusion from experiments on rocks typical of those in the mantle transition zone,a global buffer layer 410 to 660 kilometres beneath us that separates the upper from the lower mantle.
They are also one of the prime sources of information about completely inaccessible rocks such as those in the Earth's lower mantle and in the mantles of the other terrestrial planets and the Moon.
Scientists analyzed 46 blue diamonds, including one from South Africa that sold for $25 million in 2016, and determined that they can form at depths of at least 410 miles(660 km),reaching into a part of the Earth's interior called the lower mantle.
Those conditions to form the inclusions would only be found at depths greater than 435 miles(700 km) in the lower mantle, suggesting the material cycled from the surface down to the Earth's interior.
For instance, oceanic crust loaded with carbon-rich sediment could delve, or subduct, to mix with the upper mantle layer of hot rock that reaches about 410 miles(660 kilometers) down,or even to the lower mantle below that.
Other observations suggest no chemical difference between the upper and lower mantle, leading some to argue for what's called a"well-mixed mantle," with both the upper and lower mantle participating in the same heat-transfer cycle.
So the“softer” areas of the 660 kilometer limit could be due to a more complete mix, while mountainous andsteeper areas could have formed in places where the upper and lower mantle fail to mix so well.
A conceptual model showing that the diamonds andinclusions form in the lower mantle in subducted oceanic crust, are then transported by mantle flow to the upper mantle, and finally to the surface in a kimberlite magma.