Geophysical studies have revealed that the Earth has several distinct layers. Each of these layers has its own properties. The outermost layer of the Earth is the crust. This comprises the continents and ocean basins. The crust has a variable thickness, being 35-70 km thick in the continents and 5-10 km thick in the ocean basins. The crust is composed mainly of alumino-silicates
The next layer is the mantle. It is about 2900 km thick, and is separated into the upper and lower mantle. This is where most of the internal heat of the Earth is located. Most of the Earth's mass is in the mantle, which is composed of iron (Fe), magnesium (Mg), aluminum (Al), silicon (Si), and oxygen (O) silicate compounds. At over 1000 degrees C, the mantle is solid but can deform slowly in a plastic manner.
The last layer is the core, which is separated into the liquid outer core and the solid inner core. The outer core is 2300 km thick and the inner core is 1200 km thick. The outer core is composed mainly of a nickel-iron alloy, while the inner core is almost entirely composed of iron. Earth's magnetic field is believed to be controlled by the liquid outer core.
2007-01-29 04:09:42
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answer #1
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answered by GatorGal 4
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No one knows for sure. The latest theory is that it is like a giant nuclear reactor.
2007-01-29 11:59:41
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answer #2
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answered by Give life. Be an organ donor! 4
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The core is mostly liquid iron and rock at about 5000C, or so most scientists think.
2007-01-29 11:54:48
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answer #3
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answered by Anonymous
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I will be going there next week I will let you know
2007-01-29 11:57:29
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answer #4
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answered by Anonymous
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dirty, really really dirty
2007-01-29 16:07:30
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answer #5
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answered by eyesinthedrk 6
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