Subduction zones happen where plates collide. When two tectonic plates meet it is like the immovable object meeting the unstoppable force. However tectonic plates decide it
by mass
. The more massive plate, normally a continental will force the other plate, an oceanic plate down beneath it.
What causes one plate to Subduct?
Subduction is possible because the cold oceanic lithosphere is slightly more dense than the underlying asthenosphere, the hot, ductile layer in the upper mantle underlying the cold, rigid lithosphere. Once initiated, stable subduction is driven mostly by
the negative buoyancy of the dense subducting lithosphere
.
What determines whether a plate will Subduct at convergent plate boundaries?
If the two plates that meet at a convergent plate boundary both are of oceanic crust, the
older
, denser plate will subduct beneath the less dense plate.
Which plate will always Subduct?
When an oceanic plate converges with a continental plate,
the oceanic crust
will always subduct under the continental crust; this is because oceanic crust is naturally denser. Convergent boundaries are commonly associated with larger earthquakes and higher volcanic activity.
What will be formed if the three plate boundaries meet in one place?
At the triple junction each of the three boundaries will be one of 3 types –
a ridge (R), trench (T) or transform fault (F)
– and triple junctions can be described according to the types of plate margin that meet at them (e.g. Transform-Transform-Trench, Ridge-Ridge-Ridge, or abbreviated F-F-T, R-R-R).
What is the three types of convergent plate boundaries?
Convergent boundaries , where two plates are moving toward each other, are of three types, depending on the type of crust present on either side of the boundary — oceanic or continental . The types are
ocean-ocean, ocean-continent, and continent-continent.
What happens when two oceanic plates collide?
A
subduction zone
is also generated when two oceanic plates collide — the older plate is forced under the younger one — and it leads to the formation of chains of volcanic islands known as island arcs. … Earthquakes generated in a subduction zone can also give rise to tsunamis.
What happens when two plates collide along a subduction zone?
Where two tectonic plates meet at a subduction zone,
one bends and slides underneath the other, curving down into the mantle
. (The mantle is the hotter layer under the crust.) … At a subduction zone, the oceanic crust usually sinks into the mantle beneath lighter continental crust.
Where does seafloor spreading occur?
Seafloor spreading occurs
at divergent plate boundaries
. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor.
Does the older or younger plate Subduct?
True subduction happens only to oceanic lithosphere. When oceanic lithosphere meets continental lithosphere, the continent always stays on top while the oceanic plate subducts.
When two oceanic plates meet, the older plate subducts
.
What is the difference between oceanic plate and continental plate?
Oceanic plates are much thinner than the continental plates
. … At the convergent boundaries the continental plates are pushed upward and gain thickness. The rocks and geological layers are much older on continental plates than in the oceanic plates. The Continental plates are much less dense than the Oceanic plates.
Does Earth become smaller or bigger when plates move?
New crust is continually being pushed away from divergent boundaries (where sea-floor spreading occurs), increasing Earth’s surface. But
the Earth isn’t getting any bigger
.
Where do 3 plate boundaries intersect?
A triple junction
is a point where the three plates, A, B, and C, meet. It is also the intersection of the boundaries between the three pairs AB, BC, and AC.
What drives the motion of the plates?
Research has shown that the major driving force for most plate movement is
slab pull
, because the plates with more of their edges being subducted are the faster-moving ones. However, ridge push is also presented in recent research to be a force that drives the movement of plates.
What are the 4 plate boundaries?
There are four main types of plate boundary. These are
constructive, destructive, conservative and collision margins
.
What are examples of convergent boundaries?
Examples. The
collision between the Eurasian Plate and the Indian Plate that is forming the Himalayas
. Subduction of the northern part of the Pacific Plate and the NW North American Plate that is forming the Aleutian Islands. Subduction of the Nazca Plate beneath the South American Plate to form the Andes.
