The two layers that the Earth's lithosphere consists
ā¢crust
ā¢upper mantle
Crust
Outermost layer of the earth or the thinnest layer
2 types of crust
Oceanic Crust- locates in the bottom of the water
Continental Crust-locates in the surface
asthenosphere
The denser weaker layer beneath the lithospheric mantle
plate tectonics
The movement of plates
Compositions of Oceanic crust
ā¢Basaltic rocks composed of silicates and magnesium (āSiMaā)
ā¢Mafic rocks
ā¢Densityā2.9g/cmĀ³
ā¢Age-oldest are less than 200 million years old
ā¢Coverage- 29% of the Earthās surface
ā¢thinner but denser
Compositions of Continental Crust
ā¢Granitic rocks composed of silicates and aluminum (āSiAlā)
ā¢Felsic rocks
ā¢Density-2.7g/cmĀ³
ā¢Age- 3.8 billion to 4 billion years old
ā¢Coverage- 71% of the Earth's surface
ā¢Thicker but less dense
Difference between focus or hypocenter to epicenter
Focus- where earthquake origates
Epicenter- lies above the focus
How can we get the time difference?
time difference formula
formula for the computed distance on the map (cm)
Identify and describe the 3 types of boundaries
The location where two plates meet
3 types of plate boundaries
ā¢Convergent plate oundaries- occurs when two plates come together; Happens in oceanic-continental, oceanic-oceanic, continental-continental
ā¢Divergent plate boundaries- occurs when two plates move apart
ā¢Transform fault boundaries- slide past each other horizontally
Geological events that occur in convergent plate boundaries
ā¢Oceanic-continental
-Subduction
-Volcanic arc
-Trench/Submarine Valley
-Earthquake
ā¢Oceanic-Oceanic
-Subduction
-Volcanic Arc
-Trench
-Earthquake
-Tsunami
ā¢Continental-Continental
-Mountain formation
-Earthquake
Geological events that occur in divergent plates boundary
ā¢Oceanic ridge
ā¢Rift Valleys
ā¢Earthquakes
Geological events that occur in transform fault boundaries
ā¢Fault lines
ā¢Earthquakes
Types of earthquakes
ā¢Shallow earthquakes
-focus is within 60 km and 85% energy released
ā¢Intermediate earthquakes
-60-300 km and 12% energy
ā¢Deep earthquakes
-300-700km and 3%
Who introduced the idea of transform plate boundaries?
John Tuzo Wilson
What is conservative type?
The lithosphere is not destroyed but rocks are displaced along the shearing zone
conservative type
The lithosphere is not destroyed but rocks are displaced along the shearing zone
shear zone
Where shallow earthquakes happen frequently