Question

Scientists have direct evidence of the Earth's structure to

1) the inner core.
2) the upper mantle (~250 km (155 mi)).
3) about 12 km (7.6 mi) from the surface.
4) 15 km (9.3 mi) from the surface, based on the deepest well shaft.
5) the Gutenberg discontinuity

Answer 1

Scientists have direct evidence of the Earth's structure to various depths, including the inner core, upper mantle, and depths close to the surface. The Gutenberg discontinuity is also an important feature.

Step-by-step explanation:

Direct evidence of the Earth's structure comes from seismic studies, including seismic waves generated by earthquakes. This evidence allows scientists to study the interior of the Earth. Among the options provided: 5) The Gutenberg discontinuity. The Gutenberg discontinuity is a boundary observed in the Earth's interior between the outer core and the mantle. It is marked by a change in the behavior of seismic waves. Below the Gutenberg discontinuity, S-waves (secondary or shear waves) do not travel through the material, suggesting that the outer core is in a liquid state. This supports scientists' understanding of the Earth's layered structure and the presence of a solid inner core and liquid outer core.