Plate Boundaries Flashcards
The edges of the Earth’s plates MEET AT PLATE BOUNDARIES
Plate Boundaries
Thea Earth’s Crust and upper mantle are broken into sections called
Litospheric Plate
A theory that explains piece of earths litospheric are in constant motion, driven by convection currents in the mantle (ASTHENOSPHERE)
Theory of Plate Tectonics
What makes the plates move?
Convection currents in the mantle move the plates as the core heats the slowly-flowing asthenosphere.
Three Types of Boundaries
Divergent Boundary
Convergent Boundary
Transform Boundary
A plate boundary where two plates move away from each other. (Rifting)
Divergent Boundary
Causes of Divergent Boundary
Seafloor Spreading
Rock gets thin in the middle as it is pulled apart. What kind of stress is this?
Tensional Stress
what happens when the rock snaps from the stress of tension?
A normal fault occurs. The rock drops down as it breaks.
A plate where two plates moves forward each other (colliding)
Convergent Boundary
A geologic feature or events may form __________ on continents
________________ in the ocean
what are the other features?
RIFT VALLEYS
SEA-FLOOR SPREADING
Mid-ocean ridges
Fissure volcanoes
A plate boundary where two plates move towards each other (colliding)
Convergent Boundary
Boundaries between two plates that are colliding. What do you call this stress?
Compression Stress
3 types of Convergent Boundary
Oceanic-Continental Plate
Oceanic-Oceanic Plate
Continental-Continental Plate
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.
Oceanic-Continental Plate
Explain Oceanic-Continental PLate
The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.
The less dense plate slides under the more dense plate creating a subduction zone called a TRENCH.
Oceanic-Oceanic Plate
Explain Oceanic-Oceanic Plate
The less dense plate slides under the more dense plate creating a subduction zone called a TRENCH.
A continental plate colliding with another continental plate
Have Collision Zones:
A place where folded and thrust faulted mountains form.
Continental-Continental Plate
What geological feature can a Continental-Continental Plate form?
Mountain Ranges
WHAT HAPPENS WHEN THE ROCK IS SQUEEZED FROM THE STRESS OF COMPRESSION?
A REVERSE FAULT
Rock is forced upward as it is squeezed.
A plate boundary where two plates move past each other in opposite direction.
Transform Boundaries
How is the rock broken at Transform Boundaries?
Rock is pushed in two opposite directions (or sideways, but no rock is lost)
Rock is pushed in two opposite directions (or sideways, but no rock is lost). This stress is called ____________
SHEARING
What can Transform Boundaries cause?
May cause Earthquakes when the rock snaps from the pressure.
A famous fault example is the San Andreas Fault in California.
WHAT HAPPENS WHEN THE ROCK IS SHEARED (OR “CUT”) FROM THE STRESS OF SHEARING?
STRIKE-SLIP FAULT
What is the super continental?
PANGAEA
Wegener said that continents move around on Earth’s surface and that they were once joined together as a single supercontinent.
Continental drift theory
