Mechanisms of Plate Movements Flashcards
Forces the either pull the tectonic plates apart of push them toward each other.
Driving forces
What are the 3 mechanisms/driving forces of plate tectonics?
Mantle convection, ridge push and slab pull
Giant pieces of the Earth’s crust that fit together and move around on the Earth’s surface.
Tectonic plates
TRUE OR FALSE
Lithospheric plates on the scales of continents and ocean floors are constantly moving in response to the movements in the mantle.
TRUE
It states gravity and the plates are the ones responsible for the tectonics through subduction process.
Slab pull theory
What term when continents and ocean basins have always been permanent features on the Earth’s surface?
Permanentism
What do you call when the rotation of the Earth created a centrifugal force towards the equator which broke the continents apart?
Pole-fleeing force
It helped revolutionize our understanding of the geology of the seafloor.
Seafloor mapping and the first detailed map of the ocean floor in 1957.
TRUE OR FALSE
Continental drift theory was widely accepted in the early ’90s.
FALSE, not widely accepted
Why the Continental Drift Theory was not widely accepted?
Due to the lack of a clear driving mechanism.
TRUE OR FALSE
Seafloor spreading shows how crust is formed on ridges and subducts or gets destroyed in trenches.
TRUE
The gravity driven mechanism involves what forces?
Ridge push and slab pull
What theory is currently accepted mechanism of the continental drift.
Mantle Convection Theory
Why the Mantle Convection Theory is currently the accepted mechanism of the continental drift?
Due to the energy given by the Earth’s internal heat.
What is circulating all throughout the mantle by the earth’s interior and surface temperature differences?
Convection current
This force takes place when a subducting plate sinks into the mantle.
Slab pull
It contains material less dense than the crustal plates riding above it.
Asthenosphere
It acts as a massive shear zone for the over-riding plate.
Asthenosphere
TRUE OR FALSE
Since the plate gets thicker and denser
further away from the spreading center, the ridge push force will increase towards the
orogenic belt.
FALSE, towards the subduction zone
This force happens between 2 colliding crustal plates where one is subducting under the other.
Slab (trench) suction
This force acts as a plate collides with another plate. It occurs only at subduction
zone wherein the subducting plate exerts a force directly onto the over-riding buoyant
plate which acts to oppose the forces driving the subduction.
Slab resistance
This convection current acts as a ______________,
wherein the lithospheric plates above were carried along with it.
Conveyor belt
TRUE OR FALSE
Plate with a slab subducting into the mantle moves slower towards
the subduction zone than those plates without a slab.
FALSE, moves faster
TRUE OR FALSE
In slab pull, as the plate sinks into the mantle, it acts to pull the rest of the
plate behind it.
TRUE
IDENTIFY
In slab (trench) suction, As the plate subducts, it creates ______________ in the upper mantle
that exert a pulling force, which acts to suck both the plates together.
convection currents
It oppose the movement of driving forces.
Resisting forces
They generate shearing or
frictional forces resisting the movement of lithospheric plates.
Resisting forces
The force that directly opposes the slab pull.
Collisional resistance
It occurs as the heavy basaltic plate
is pulled down into the mantle. Thecollisionalforce occurs because the mantle, although
less dense than the subducting plate, still resists subduction to some extent due to friction.
Collisional resistance
This force occurs when the spreading center along a ridge is broken by several
kilometers, the broken plates slide past each other and form a transform fault.
Transform fault resistance
IDENTIFY
Since the
movement is opposite, the plates encounter ____________ in the contact zones.
frictional resistance
This force is the resistance ordraggingforce associated with the interface
between the upper mantle and the lithosphere.
Drag force
It is the force that directly opposes the
movement of crustal plates.
Drag force
IDENTIFY
Any individual plate contains __________ and/or __________ crust.
Oceanic, continental
Plate boundaries are defined by what?
Active seismic and volcanic activity
What are the 2 main classes that characterized the forces acting on the plates?
Driving and resisting forces
What are the 4 driving forces?
Mantle convection, slab pull, ridge push and slab (trench) suction
What are the 4 resisting forces?
Slab resistance, collisional resistance, transform fault resistance and drag force
Occurs when warm mantle currents drive and carry plates of lithosphere along like a conveyor belt.
Mantle convection
What is the source of heat from convection?
radioactive materials
How does convection cause plate tectonics?
By the ridge push and slab pull
IDENTIFY
Slab suction compared to slab pull is _________.
weaker
Considered as the strongest of the driving forces.
Slab pull
What is the main effect of the underlying mantle?
Produce a shearing or frictional force resisting the motion of lithospheric plates.
TRUE OR FALSE
The resisting force of the mantle as the slab tries to force it way through is weaker than the shearing on the top and bottom of the descending slab.
FALSE, stronger than the shearing
TRUE OR FALSE
Friction between the converging plates and also the force required to bend a plate resist the movement of the plate at subduction zones.
TRUE
What geological features are formed when driving forces are at work?
Mountains, mountain ranges, volcanoes, ocean trenches, plateaus and valleys
Factors affecting plate movement.
Gravity, density and convection currents
TRUE OR FALSE
The more dense a plate is, the more likely it will sink.
TRUE
IDENTIFY
_____________ beneath the plates causes the plates to move.
Convection currents
Acts as a thermostat and keeps the Earth balmy.
Substances like carbon dioxide
TRUE OR FALSE
Plate tectonics do not affect humans in several important ways.
FALSE, plate tectonics affect humans
What would Earth be like without plate tectonics?
Fewer earthquakes and volcanic activity. Less mountains and no deep-sea trenches.
TRUE OR FALSE
New landmasses will be formed on the middle of divergent boundaries.
TRUE
Why plates continue to collide?
Because it has the same materials
How mountain ranges are formed?
Through collision
TRUE OR FALSE
Plates move by themselves.
TRUE
What do you call when heat energy is released?
Nuclear fission
It is the process in transferring heat.
Convection
What is the term when the heat of the core was transferred to the crust by the mantle?
Thermal convection
TRUE OR FALSE
Convection current is about the cycle of magma.
TRUE
It is used to determine the movement of the plates.
GPS System
Regarded as the most important theory ever developed in the field of geology.
Plate tectonic theory
IDENTIFY
Heat can be transferred from one place to another through a process called ____________.
Convection
IDENTIFY
One driving force behind plate tectonics is ________________.
Mantle Convection
Where does subduction process happens?
At the outer edges of plates.
Why old rocks/slabs are subducted in slab pull?
Due to gravitational forces
For oceanic-oceanic subduction, what will be subducted since it is denser?
Older and colder oceanic plate
What are the 2 main driving forces of movement of plates?
heat and gravity
Why does the outer part of mantle is in liquid form?
Due to the intense temperature
It is the opposite of convection. An example of this is when you can feel the heat from one end to another.
Conduction
IDENTIFY
Convection deals with ____________.
temperature
A cycle of distribution of heat. Kapag yung liquid or gas ay mas malapit sa mainit, gagaan at papaibabaw. Papalitan nya yung cold materials sa itaas na mabigat, yun naman ang bababa close to the outer core.
Mantle Convection process
hotter = _______
less dense
TRUE OR FALSE
The mantle convection process will take millions of years to complete.
TRUE
Where does the subducting plate happens?
It sinks into the mantle.
What zone that has subducting plates?
Subduction zone
TRUE OR FALSE
Slab pull, it is the gravity that is pulling the slabs. As well as the mantle convection, the slabs are pulling downward into the mantle.
TRUE
What is the result of a slab pull?
Ridge push
What is an example of ridge push?
Seafloor spreading
TRUE OR FALSE
Paikot-ikot yung mantle convection kaya nahihila yung asthenosphere, then may tutulak na magma. Hihilahin rin pababa ng slab push. Kapag tinulak, magkakaroon ng slab pull.
TRUE
TRUE OR FALSE
Convection traction, ridge push and slab pull are sometimes on cycle.
FALSE, always on cycle
What is mostly encountered in resisting forces?
Friction
Even though tectonics plates are continuous in movement, it can still stop (hindi kaya nito magtuloy-tuloy). What force is being referred here?
Resisting force
Why there are friction?
Because of the materials.
Natural forces that act upon on Earth.
Gravity
It talks about the composition of a material or plate has. If it has a greater density, it will sink.
Density
Factors affecting plate movements.
Gravity, density and convection currents
TRUE OR FALSE
Because of the plate movements, it led to the formation of the 7 continents and will also experience earthquakes and volcanic eruptions.
TRUE
What is being compared to the mantle convection theory because of its cycle?
Conveyor belt
Slab pull : ?
Gravity/gravitational pull
What are ways to transfer heat?
Convection, conduction and radiation
TRUE OR FALSE
An example of radiation is the sun and microwave since it is has a source of heat.
TRUE
TRUE OR FALSE
Ice cooling down your hand is an example of convection.
FALSE, it is an example of conduction
