What Was the Unexpected Contribution of Keith Runcorn and His

question 60

Multiple Choice

What was the unexpected contribution of Keith Runcorn and his students to the continental drift controversy?

• A) Apparent polar wander paths for rocks of various ages in Europe demonstrated that either the magnetic pole, or the continent's position, had wandered with time.
• B) Magnetic stripes on the seafloor demonstrated magnetic reversals and seafloor spreading.
• C) Reversed magnetic north directions preserved in rocks demonstrated that the location of Earth's axis had changed markedly throughout time, implying periodic cataclysms that shifted the continents during pole reversals.
• D) Discordance of the Earth and Moon's magnetic pole orientations proved that the poles of one or both had drifted with the lithosphere since they were formed.

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