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Is it true that the South Pole and North Pole are interchanging over a period of 500000 years time?

I read in a science book that the North Pole and South Pole are interchanging their position over a period of 500000 years. This process goes on slowly by the clock wise tilting of the earth over these long period. If so,it sounds contradictory to the theory of continental drift. Explain me the truth.

Public Comments

1. Not their position, but the direction of the magnetic field
2. The magnetic poles of the earth reverse on an average of about every 500,000 years. The last change was about 700,000 years ago HOW IT WAS NOTICED: When lava pours from a volcano, it solidifies to a black rock called basalt. Basalt is slightly magnetic, and it takes on the direction of the surrounding magnetic field at the time it solidifies. Scientists examined lavas for their magnetism early in this century (I believe) to see how consistent the direction of ancient magnetic fields was with the direction we observe now (would compasses point in the same direction?). The directions generally agreed, but there existed reversals of directions which suggested that there were times in the past when the poles were roughly interchanged. No one knew what to make of it. Some suggested "polar wandering", that the whole surface of the Earth slid around the interior like a loose shell. WHO DISCOVERED: I don't remember. Check a book by Allan Cox, a collection of historic articles. But a big change happened in 1963. People noted that while rocks on Earth were magnetized in a disordered way, the sea bottom was magnetized in long strips. Larry Morley (whose article was regarded so speculative that journals would not publish it) and then Matthews and Vine (who managed to publish) suggested that molten rock was spreading out like a conveyer belt from volcanic cracks in the middle of the ocean floor, e.g. the one in the middle of the Atlantic (Azores islands sit on it). Or rather like 2 belts, one moving towards Europe, one towards America, carrying on them the continental plates, so that Europe and America gradually drift apart. As each belt comes out of the crack, its lava solidifies to basalt, causing it to become magnetized, and when the field reverses, its magnetization reverses too. So the bottom of the ocean records the field like the tape of a tape recorder, containing perhaps 50 million years of record. HOW LONG AGO: about 700,000 years, according to the "tape recorder" HOW MANY TIMES: Many, about half a million years apart on the average.
3. i think it is true that earth's magnetic poles have been interchanged,watched in tv
4. The polarity has switched getting on for sixty times over the last 65 million years. This can be used for the purposes of dating rock in some cases. For example, during the very end of the Cretaceous and the beginning of the following Paleocene, the polarity of the planet was "reversed"; ie. the magnetic pole was to the south. Seen in such terms, that slice of time is known as C29r. It was followed by C29n (n = "normal"), C28r, C28n and so on. "Normal" isn't actually literally normal in terms of the experience of the planet. It refers to what we perceive to be normality. The average length of time between polarity shifts is more like a bit over a million years rather than half-a-million. There's no contradiction involved with continental drift theory. Actually, the demonstrable presence of zones with different polarities in similar patterns on both sides of oceans is evidence supporting continental drift.