Environmental Science | Plate Tectonics Flashcards
(30 cards)
How many major layers does the Earth have?
4 (Lithosphere, Mantle, Outer Core, Inner Core).
What is the outermost layer of the Earth called?
Lithosphere (or crust).
Name the three types of rocks in the lithosphere.
Sedimentary, igneous, metamorphic
What is the boundary between the crust and mantle called?
Mohorovicic discontinuity (Moho).
Is the mantle solid or liquid?
Acts like a fluid, but is made of rock.
What causes the mantle’s rock to behave like a fluid?
High pressure and temperature.
What is the outer core made of?
Liquid iron.
Why is the inner core solid despite being hotter?
Immense pressure compacts atoms.
What drives tectonic plate movement?
Convection currents in the mantle.
What is the upper portion of the mantle called?
Asthenosphere.
What happens at a convergent boundary?
Plates collide; subduction or uplift occurs.
Name two landforms created at convergent boundaries.
Mountains, trenches, or volcanoes.
What is the Mid-Ocean Ridge?
Underwater mountains formed at divergent boundaries.
How does a rift form?
Plates pull apart less forcefully.
What happens at a transform boundary?
Plates slide past each other, causing friction.
What is the focus of an earthquake?
The point where plates slip underground.
How are fault-block mountains formed?
One plate is forced upward.
What is the Ring of Fire?
A Pacific Ocean zone with frequent volcanoes/earthquakes.
Why do subducting plates create volcanoes?
Melting crust releases magma.
What are seismic waves?
Energy released during an earthquake.
How do convection currents relate to plate tectonics?
They transfer heat, moving the asthenosphere and dragging plates.
Contrast oceanic vs. continental crust density in subduction.
Oceanic crust is denser and subducts.
Why is the inner core solid while the outer core is liquid?
Pressure overrides temperature in the inner core.
Explain how the Moho was discovered.
Seismic wave speed changes revealed the boundary.
