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Geology/Core of the Earth

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QUESTION: Hi,

From what I read, the center of the planet is a solid core that is made of nickel and iron and it is surrounded by a liquid core. My question is since we haven't been able to drill that deep into the planet, how do we know what the planet's core is like? thanks

Jackie

ANSWER: The makeup of the interior of the earth is derived from inference due to the fact that the Earth has a magnetic field and the prevalence of iron in the crust.   Our knowledge of petrography, or the formation and occurance of rocks along with mineralogy tells us that certain conditions of pressure and temperature cause elements of behave in certain ways.  Then there is use of geophysics.  Geophysics tell us that the center of the earth is stratified in density.  Along with the other bits and pieces it allows us to make an educated postulation of how we think the interior looks.  

---------- FOLLOW-UP ----------

QUESTION: Thanks for the answer.

I have a follow up question. I don't want to get all conspiracy theory on you but it is possible for a planet (not Earth) to be hollow? This has nothing to do with the Hollow Earth Theory. I'm just curious whether or not it is possible for that to happen or would that question be referred to an astrophysicist.

Answer
Probably not since the planet would be dead.  If the interior were hollow, imagine what would happen to it should a meteor or asteroid of any size were to strike it.

Hollow would mean the planet had cooled, and contracted.  If our planet completely cooled the Van Allen belt would cease and its our primary protection against cosmic radiation which would then begin to strip off our atmosphere.  You can imagine what would happen next.  I don't know if all life would die due to the radiation before the atmosphere got to the point that it could no longer sustain life.

So a hollow planet would have no Van Allen belt like magnetic shield.

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Keith Patton

Expertise

I can answer questions concerning physical and historical geology, environmental geology/hydrology, environmental consulting, remote sensing/aerial photo interpretation, G&G computer applications, petroleum exploration, drilling, geochemistry, geochemical and microbiological prospecting, 3D reservoir modeling, computer mapping and drilling.I am not a geophysicist.

Experience

I have 24 years experience split between the petroleum and environmental industries. I have served as an expert witness in remote sensing, developmental geologist, exploration geologist, enviromental project manager, and subject matter expert in geology and geophysical software development.

Organizations
American Association of Petroleum Geologists
American Association of Photogrammetrists and Remote Sensing

Education/Credentials
Bachelor and Master of Science
Registered Geologist in State of Texas

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