In 1960, Harry Hess & Robert S. Dietz proposed a theory of Sea-Floor Spreading
12. C
Heat in the mantle comes from the Earth's molten outer core, decay of radioactive elements and, in the upper mantle, friction from descending tectonic plates. The heat in the outer core results from residual energy from the Earth's formative events and the energy generated by decaying radioactive elements.
13. C
The mid-ocean ridges are the earth’s largest volcanic system, accounting for >75% of all volcanic activity on the planet. The heat from this volcanism is dispersed by hydrothermal circulation of seawater.
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Answer:
11. B
In 1960, Harry Hess & Robert S. Dietz proposed a theory of Sea-Floor Spreading
12. C
Heat in the mantle comes from the Earth's molten outer core, decay of radioactive elements and, in the upper mantle, friction from descending tectonic plates. The heat in the outer core results from residual energy from the Earth's formative events and the energy generated by decaying radioactive elements.
13. C
The mid-ocean ridges are the earth’s largest volcanic system, accounting for >75% of all volcanic activity on the planet. The heat from this volcanism is dispersed by hydrothermal circulation of seawater.