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Area in the Earth's mantle hot enough to melt rock into magma and create volcanoes?
All of the Earth's mantle is hot. And while some geologists believe that there are Mantle plumes (or hot spots) current evidence seems to support a view that mantle plumes do not exist. What causes magma to rise up from the lower crust and mantle is the convection of the mantle and therefore the places where most heat (and magma) is coming up to the surface is along the mid oceanic ridges.
Why does magma rise when it is nearer to the core?
Water that is heated expands and rises to the surface of the tray. Similarly, the magma expands and rises to the surface of the tray. Similarly, the magma nearer the core expands and rises to top of the mantle.
Why does magma rise toward the crust and not sink into the mantle?
By being less dense than, so slightly buoyant in, the surrounding rock.
Which of the following is part of the Earths lithosphere SoilMagma None of these Mantle, magma, and soil Mantle?
magma
What causes magma to rise to earths surface?
The magma is in the mantle, the layer under the crust. There is a convection current caused by radioactivity in the inner core which causes the plates to move. Therefore the constructive plates move apart which means magma can rise up. It'll then solidify and this is what makes volcanoes. Hence CONSTRUCTive.
What is a hot plume model?
The theory that plates diverge where large columns of hot magma, called hot spots, rise from the lower mantle
What does the mantle secrete?
Magma
Why does magma in the mantle rise through the crust above it?
magma comes from the outer core and when an earthquake or something happends, a crack froms and the pressure of lava shoots up like a geyser.
Can you get to the surface by riding a magmatic eruption all the way from the core to the surface?
No. This could not be done, even assuming you found a way to protect yourself from the immense heat and pressure. Magma forms in the upper mantle, not the core. Pressure in the lower mantle is too high for rock there to melt. During an eruption the magma does not usually come directly from the mantle but from a magma chamber a few miles underground. The mantle does convect, with material rising from near the core-mantle boundary, but this process is very slow; a plume takes about 50 million years to rise from the bottom of the mantle to the top. The core itself is not made of magma either, but metal.
Why does oceanic crust melt?
At mid-ocean ridges, such as the Atlantic Rise and Pacific Rise. As two plates move apart the crust is stretched and thinned, causing less pressure on the mantle immediately below. Due to this drop in pressure the mantle undergoes "decompressional melting" allowing magma to form. This magma is less dense than the surrounding mantle and rises at the mid-ocean ridges, cooling and forming new oceanic crust.
Is magma released from volcanoes material from the core?
No, magma is not material from the core of the Earth. Magma is molten rock that is generated in the Earth's mantle, which lies between the core and the crust. Magma can rise to the surface during volcanic eruptions, forming lava flows or erupting explosively.
How can volcanoes sometimes have more then one kind of eruption?
Well, the magma reservoir or chamber beneath every volcano gets it's fuel from the Earth's mantle (a layer of seething magma). So every time a volcano erupts, emptying or lowering the level of magma in the chamber, some magma from the mantle will rise (over time) to fill the gap.
