Download 1 a) Why is it difficult to determine Earth`s inner structure? It is so

Earth’s Interior Objective 7: Section 1 Assessment Questions
1 a) Why is it difficult to determine Earth’s inner structure?
It is so difficult to determine Earth’s inner structure because we cannot actually view the interior of
the Earth. Due to the intense heat and pressure, technology has not been able to penetrate past 12
km into the Earth. As a result, we must use seismic waves and other indirect methods to get an idea of
what Earth’s interior is really like.
1 b) How are seismic waves used to provide evidence about Earth’s interior?
Seismic waves are used to provide evidence about Earth’s interior because by studying how they travel, we
can detect what the Earth’s interior is really like. The waves’ speed and path provide us with details about the
Earth’s structure. Seismic waves told us that the Earth was divided into layers. For example, certain waves
cannot travel through liquids, which indicated that the outer core was made of liquid.
2 a) List Earth’s three main layers.
Mantle, core, and crust
2 b) What is the difference between the lithosphere and the asthenosphere? In which layer is each
located?
The lithosphere is the rigid layer that floats on top of the asthenosphere. The lithosphere is home of
the plates and is made up of both the crust and the uppermost part of the mantle. The asthenosphere
is the soft layer in the upper mantle that lies right below the lithosphere.
2 c) Classify each of the following layers as liquid, solid, or solid but able to flow slowly: lithosphere,
asthenosphere, lower mantle, outer core, inner core
Lithosphere: solid
Asthenosphere: solid but able to flow slowly
Lower Mantle: solid
Outer Core: liquid
Inner Core: solid