Is there a scientist out there willing to explain, in layman's terms, how and why a reversal of the Earth's Magnetic Poles can occur without any effect on a magnetized asthenosphere.

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"The asthenosphere is ductile and can be pushed and deformed like silly putty in response to the warmth of the Earth. These rocks actually flow, moving in response to the stresses placed upon them by the churning motions of the deep interior of the Earth. The flowing asthenosphere carries the lithosphere of the Earth, including the continents, on its back."