Layers of the earth Flashcards
What key evidence supports the idea that Earth is not hollow?
High average density and seismic wave behavior
Which type of seismic wave cannot travel through liquid?
S-waves
What causes the P-wave shadow zone?
Refraction at the core–mantle boundary
What seismic evidence suggested the discovery of Earth’s inner core?
P-wave velocity increases after passing through the center
What is the Moho boundary?
Boundary between crust and mantle
What does isostasy explain?
How mountains float on denser material below
Which layer is brittle and conducts heat rather than convecting it?
Lithosphere
What is the typical near-surface geothermal gradient?
25°C per km
What makes mantle convection possible?
Rayleigh number much greater than 2000
What are Benioff zones associated with?
Subduction zones and volcanic activity
