chapter 25.3 and 25.4 Flashcards
What is the boundary that marks the density change between layers?
discontinuity
How can discontinuities be identified?
Seismic waves
What is a shadow zone?
no seismic waves have been recorded
What is another term for shadow zone?
dead zone
What are the degrees that shadow zones can fall between?
- 105
- 140
Is the outer core a solid or a liquid?
liquid
Is the inner core a solid or a liquid? Why?
Solid because the pressure
What makes up the lithosphere?
crust and uppermost mantle
What is the asthenosphere?
plastic like layer upon which which Earth’s plates move
Which elements make up the mantle?
- Calcium
- Aluminum
- Iron
- Magnesium
Which elements make up the core?
- Iron
- Nickel
viscosity
the measure of a fluids resistance to flow
silica
chemical compound silicon dioxide which is a common ingredient in most magma
cinder cone volcanoes
tend to be a small, have heights on the hundreds of meter range, and have short eruption cycles
shield volcanoes
broad,flat structures composed of layer upon layer of lava flows
composite volcanoes
large and steep-sided, often thousands of meters high and tens or kilometres across the base, and composed of both layers of lava and ash
what is molten or liquid rock stored inside earth called?
magma
where is the ring of fire located?
Pacific ocean
what forms when tectonic plates collide along subduction zone?
valcanoes
what two specific locations have volcanic activity do to divergence?
- mid-atlantic ridge
- east african rift valley
are hot spots stationary?
yes
what are created from hot spots?
islands (the Hawaii islands)
if a viscosity is higher,is it going to flow slower or faster?
slower
if magma has higher viscosity, is it going to have more silica?
yes
