Earth Science Quiz: Layers of the Earth

Study Notes

Earth's Composition and Structure

Oxygen is the most abundant element in the Earth's crust.
The inner core is primarily composed of iron and nickel.
High pressure keeps the solid state of materials in the inner core despite extreme temperatures.

Mechanical and Chemical Layers

Mechanical layers include the lithosphere, asthenosphere, mesosphere, outer core, and inner core.
Chemical layers consist of the crust, mantle, outer core, and inner core.

Earth Layer Boundaries

Discontinuities indicate boundaries between Earth's layers:
- Conrad Discontinuity: separates the upper and lower crust.
- Mohorovicic Discontinuity (Moho): boundary between the crust and mantle.
- Gutenberg Discontinuity: boundary between the mantle and outer core.
- Lehmann Discontinuity: boundary between the outer and inner core.

Seismic Waves and Earth's Layers

Seismic wave behavior provides insight into Earth's internal structure:
- Primary waves (P-waves) can travel through solid and liquid, but are refracted at core boundaries.
- Secondary waves (S-waves) only travel through solids and are absorbed in the outer core.
Time measurements of seismic waves help determine the solid, liquid, and gas states of Earth's layers.

Density and Velocity of Seismic Waves

In 1909, Andrija Mohorovicic discovered changes in seismic wave velocity, indicating layered density differences within the Earth.
The presence of a shadow zone for P-waves suggests a core composed of different material than the mantle, confirming the existence of the outer core as a liquid layer.

Description

Test your knowledge on the Earth's structure with this quiz focused on the layers of the Earth, including the inner core and the mechanical and chemical components. Challenge yourself to answer questions about the properties of these layers and key concepts like the Conrad Discontinuity.