Vocabulary
The pieces of the earth’s crust that move slowly on the top of the mantle
tectonic plates
Which layer of the earth is made of solid iron and nickel?
inner core
The area around the Pacific Plate where many earthquakes and volcanoes occur is called ____.
the ring of fire
Why do tectonic plates move?
because of convection currents in the mantle
Most earthquakes and volcanoes occur where?
along plate boundaries
A crack or rift in the earth’s crust
fault
Which layer of the earth measures between 4 and 40 km thick?
crust
What is the theory of Continental Drift?
the idea that the continents move slowly over a long period of time because of convection in the mantle
transform boundary
The place where an earthquake is felt the strongest is called
the epicenter
The “super continent” that was believed to exist millions of years ago on earth
pangea
Which is the thickest layer of the earth?
mantle
Why do we have more volcanoes here in CR than they have in many other countries?
because we are located near/on the ring of fire
When two tectonic plates move towards each other and collide
convergent boundary
How are earthquakes measured?
Richter Scale and Moment Magnitude scales measures magnitude- scale of 1-10
The boundary between two plates that are moving apart or rifting
divergent boundary
What is the lithosphere?
the crust and the very top part of the mantle that we use to study plate tectonics
What was the name of the scientist who developed the Continental Drift theory?
Alfred Wegener
There are two types of convergent boundaries. What are they called and what kind of land forms do they produce?
subduction (produce volcanoes and trenches) and collision (produce mountains)
Which three things make up “tephra”?
ash, cinders, lava bombs
When a less dense plate slides below a more dense plate
subduction zone
Why is the inner core solid?
because it has the pressure of all the other layers on top of it
What is the lithosphere and why do we study it when studying earthquakes and volcanoes?
lithosphere- made up of crust and upper mantle
understanding tectonic plates helps us understand why earthquakes and volcanoes happen
How do volcanoes form under the ocean when there is no fault or plate boundary?
hot spots: weak spots in the earth’s crust
What is the name for the avalanche of volcanic materials that can travel up to 200 kph?
pyroclastic flow