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Which of the following is good evidence for a solidified, inner core?

A) P-waves slowing down
B) S-waves stopping abruptly
C) Mantle convection currents
D) Magnetic field fluctuations

User Maras
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1 Answer

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Final answer:

S-waves stopping abruptly is good evidence for a solidified inner core, as discovered by Inge Lehmann, since shear waves cannot travel through a liquid, indicating a solid inner core within the liquid outer core maintained by radioactive decay.

Step-by-step explanation:

The best evidence for a solidified, inner core is B) S-waves stopping abruptly. geophysicist Inge Lehmann interpreted seismological data that revealed interesting properties about Earth's inner structure. She discovered that shear waves, or S-waves, which cannot travel through a liquid, abruptly stop at the core, indicating that the outer core is liquid. However, compression waves, or P-waves, do pass through the core, suggesting that the innermost part is solid. This phenomenon allows us to deduce the presence of a solidified inner core within the liquid outer core.

This understanding is corroborated by knowledge about how the Earth's core has remained hot over billions of years, primarily due to the radioactive decay of primordial elements. This heat ensures that the outer core remains in a liquid state while pressure and temperature conditions allow the inner core to solidify.

User Bon
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