Seismic waves
The shock waves become after the movements of two massive rocks
P- Waves ( Primary Waves)
Upper layer of the earth’s mantle, below the lithosphere
Asthenosphere
At what rate do tectonic plates move?
2.5-5 cm (1-2 inches) per year
large, broad, domed structures formed by layers of lava that flow out of the vent and accumulate over time
Shield volcanoes
Scientists use this scale to measure and compare earthquakes
the Richter scale
The wave created after the reflection of primary waves
S waves (secondary waves)
What are the two types of crust?
Oceanic and continental crust
How many primary tectonic plates are there?
There are seven primary tectonic plates
These are made of a volcanic rock named scoria which are small bits of lava ejected by volcanic glasses that harden in mid air. Since scoria is never thrown very far from the vent cinder cones are steep
Cinder cone
Instruments used to record the motion of the ground during an earthquake
Seismographs
When the released energy comes on the surface of the earth
L- Waves (Surface waves)
The spot where the earthquake is actually generated is usually hundreds of feet below the surface
Focus
What causes the plates to move?
The tectonic plates float on top of the asthenosphere, which influences the speed and direction of of where the tectonic plates move
they are formed out of alternating layers of pyroclastic material and lava. (Steep and strong)
Stratovolcanoes
convergent plate boundaries
Surface wave causing the ground to shake in an elliptical motion
RAYLEIGH WAVES
The point of the “focus” on Earth's surface
Epicenter
Where are tectonic plate boundaries located
The edges of Earth's lithospheric plates have boundaries which are both well defined and poorly defined. Well-defined boundaries include mid-ocean ridges and ocean trenches.
these are underwater volcanoes. Not explosive so they generally create a different type of lava called pillow lava (tube shaped).
Submarine Volcanoes
What are the three types of plate boundaries called?
Divergent boundary (two plates move away from each other), Convergent boundary (two plates collide), Transform boundary (two plates scrape past one another)