Guest CaptainStrange Posted March 7, 2004 Posted March 7, 2004 Anyone whos worth their salt should know that every few million years the earth switches polarity. But does anyone know why? I dont think it has anything to do with the earths orbit of the galaxy, but is it something to do with the fact that it is on the edge of it? is it instantaneous or over the course of a long time? And I heard some crazy person say that it causes the earth to stop spinning for a few days, is that really true???
Sayonara Posted March 7, 2004 Posted March 7, 2004 Mwaaaa ha ha haaaaaaa. You need to read this: http://www.scienceforums.net/forums/showthread.php?s=&threadid=550&highlight=pole+shift Then this: http://www.scienceforums.net/forums/showthread.php?s=&threadid=777 Then this: http://www.scienceforums.net/forums/showthread.php?s=&threadid=855 They should help. Actually wait... they probably won't.
psi20 Posted March 7, 2004 Posted March 7, 2004 In 8th grade, we studied plate tectonics, heat convection, and continental drift in the same chapter of the geology book. It talked about earth changing poles and not having poles before in the last chapter. If I recall correctly, it has something to do with the change in rotations of the cores. I think the outer core moves one way while the inner core moves the other way. Or maybe the inner core doesn't spin at all? I don't remember.
-Demosthenes- Posted March 7, 2004 Posted March 7, 2004 It changes poles! That sounds absurd, is it true?
Crash Posted March 7, 2004 Posted March 7, 2004 yes it is true, happens once in a blue moon <-(long long time)
Sayonara Posted March 7, 2004 Posted March 7, 2004 -Demosthenes- said in post #4 :It changes poles! That sounds absurd, is it true? How many fking times? READ THE DAMNED THREAD. THAT INCLUDES LINKS.
Guest Vicious Posted April 15, 2004 Posted April 15, 2004 The earth does in fact change polarity about every 600,000 years. This change in polarity is caused by a change in the flow of the layer of molten liquid iron which lies 3,000-5,000 km beneath the earth's surface. This molten iron, which is an electric conductor, is responsible for the earth's magnetic field and exactly mirrors the magnetic field. Satellite imaging of the earth shows the magnetic field lines of the earth, some of which have recently been the reverse of what they have normally been, which indicates that the earth's polarity may in fact be about to flip. The last recorded flip was about 780,000 years ago so we're actually a little overdue for a flip. By analyzing the layers of rock underneath lakes and oceans, geologists have seen rock layers that are oppositely polarized and thus have determined that, in order for this to occur, the earth's magnetic field must have flipped. By determining the distance in between the layers, and by using carbon dating, geologists have determined that these flips occur about 600,000 years apart from each other. They have also determined that a flip can take anywhere from 3,000 to 11,000 years and that it takes less time to flip at the equator thatn it does at the poles.
swansont Posted April 15, 2004 Posted April 15, 2004 The last recorded flip was about 780' date='000 years ago ... and by using carbon dating, geologists have determined...[/quote'] Given the time scale and that they aren't dating stuff that was once alive, Carbon dating would not be used. It's only useful out to 50k years or so, and only on organic material that takes in carbon from the atmosphere (i.e. CO2).
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