Plate Tectonics & Seafloor Spreading
What are the 4 lines of evidence Alfred Wegener proposed for Continental Drift?
1) Continental Puzzle (South America & Africa's coasts fit together like puzzle pieces)
2) Matching Mountain Ranges (Appalachian Mountains & East African Mountain Range are same exact rock type and age)
3) Matching Fossils (Fossils of same species across all continents)
4) Ancient Climates (Evidence of Glaciation on Africa & Coal Deposits on Antarctica)
Which layer or layers create the magnetosphere or the invisible magnetic field around Earth that protects us from harmful UV rays and breaks up asteroids in our atmosphere?
The inner and outer core. The inner core is solid and the outer core is liquid. Both are made from Iron (Fe) and Nickel (Ni).
What is subduction?
The process by which a denser plate falls beneath a less-dense plate.
What are the 3 types of seismic waves?
S - Shearing
P - Compression
L - Love/Surface Waves (the most dangerous/destructive)
What does pyroclastic mean?
Firey sediments
What did Alfred Wegener discover?
Continental Drift - that the continents were slowly drifting throughout time and were all once together in a supercontinent called Pangea (meaning "all Earth")
What do the chemical layers of Earth tell us?
What each layer is made of. For example, the core is made of Iron (Fe) & Nickel (Ni)
What is a convergent plate boundary and one example?
EX: The Himalayan Mountains
What is a fault?
A crack in the crust that makes up Earth's surface.
Which type of plate boundary creates a volcano as a landform?
Oceanic-Continental Convergence
What did Alfred Wegener NOT know?
WHY/HOW the contients were moving = PLATE TECTONICS
What do the physical layers of Earth tell us?
How each layer moves or break/how it responds to stress
What is a divergent plate boundary and an example?
Two plates moving aprat or away from each other.
EX: Mid-Oceanic Ridge or Seafloor Spreading Center
What is a normal fault, and which type of force is associated with it?
Moving apart = EXTENSION/TENSION
What are the 4 main types of volcanoes?
1) Shield
2) Composite or Stratovolcano
3) Cinder Cone
4) Supervolcano
What is the driving force that moves the tectonic plates that was discovered during WWII?
SEAFLOOR SPREADING
Which physical layer are the tectonic plates found in?
The lithosphere
What is a transform boundary and an example?
Two plates that slide past each other and often create faults and/or shallow earthquakes.
EX: The San Andres Fault on the coast of California
What is a reverse fault, and which type of force is associated with it?
Moving together = COMPRESSION
What is viscosity?
How thick/dense a liquid is - this changes how fast it flows.
Increased temperature = Decreases viscosity
Honey vs. Water
Describe a convection current and how it drives seafloor spreading. What is created at seafloor spreading centers?
Convcetion currrents are drien by hot liquid/gas rising and cool liquid/gas falling. This is driven by density differneces: hot things are heavier/denser and cool things are heavier/denser. This is how lava lamps, boiling water, and hot air balloons work. Hot magma in the mantle moves up to the crust and spews outh at mid-oceanic ridges and creates new baby crust. This is seafloor spreading.
Which physical layer are convection currents found in?
The asthenosphere
What are the two types of crust and what are each made of?
OCEANIC: Basalt (a dark-colored or mafic igneous rock) = created from mid-oceanic ridges
CONTINENTAL: Granite (a light-colored or felsic igneous rock) = created from volcanoes
What is a transform or strike-slip fault, and which type of force is associated with it?
Slides past = SHEARING
What are the two types of lava/magma?
Basaltic
Rhyolitic