What is a spreading plate boundary?
Spreading centers occur at the boundary between two plates that are moving apart, called divergent plate boundaries. Here the plate motion opens a gap between the plates and magma from the mantle rises up through it.
How could you tell a spreading center from a subduction zone?
What is plate tectonics?
- Spreading centers occur where two plates are moving away from each other, and deep cracks are opened through the crust.
- Subduction zones are associated with regions where two plates are moving towards each other, and the crust of the earth is shortened.
What is subduction boundary?
convergent plate boundary
If two tectonic plates collide, they form a convergent plate boundary. Usually, one of the converging plates will move beneath the other, a process known as subduction.
What is the difference between a subduction boundary and a collision boundary?
Destructive (or convergent) is where the two plate push into each other, but one – the oceanic plate – is heavier and more dense, so is pushed under the lighter continental plate, this is known as subduction. Collision are when two plates push together, as above, but they’re both continental plates.
What is meant by seafloor spreading?
Seafloor spreading is a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other. Seafloor spreading and other tectonic activity processes are the result of mantle convection. Mantle convection is the slow, churning motion of Earth’s mantle.
What is spreading site in geography?
Divergent Boundaries
The sites where the plates move away from each other are called spreading sites. The best-known example of divergent boundaries is the Mid-Atlantic Ridge. At this, the American Plate(s) is/are separated from the Eurasian and African Plates.
What type of boundary would be found at spreading centers?
Divergent boundaries
Divergent boundaries. Divergent boundaries occur along spreading centers where plates are moving apart and new crust is created by magma pushing up from the mantle.
What is sea floor spreading and subduction?
sea-floor spreading — a hypothesis, proposed in the early 1960s, that new ocean floor is created where two plates move away from one another at mid-ocean ridges. subduction zone — a long, narrow zone where one lithospheric plate descends beneath another.
What is another word for subduction?
What is another word for subduction?
| subtraction | deduction |
|---|---|
| taking away | lessening |
| markdown | rollback |
| knock-off | abstraction |
| discounting | docking |
Where does seafloor spreading occur?
the mid-oceanic ridge
Sea-floor spreading is what happens at the mid-oceanic ridge where a divergent boundary is causing two plates to move away from one another resulting in spreading of the sea floor.
What are the three types of plate boundaries differentiate these three types of boundaries?
Divergent boundaries — where new crust is generated as the plates pull away from each other. Convergent boundaries — where crust is destroyed as one plate dives under another. Transform boundaries — where crust is neither produced nor destroyed as the plates slide horizontally past each other.
What are the two types of boundaries?
There are essentially three types of plate boundaries, which are divergent, convergent, and transform. In the case of divergent plate boundaries, two of earth’s plates move away from each other.
What type of boundary is seafloor spreading?
Sea-floor spreading is what happens at the mid-oceanic ridge where a divergent boundary is causing two plates to move away from one another resulting in spreading of the sea floor. As the plates move apart, new material wells up and cools onto the edge of the plates.
Why is seafloor spreading important?
Today it refers to the processes creating new oceanic lithosphere where plates move apart. Seafloor spreading replaces the lithosphere destroyed by subduction, and exerts important influences on Earth’s chemical and biological evolution.
What causes seafloor spreading?
Seafloor spreading creates new crust. Subduction destroys old crust. The two forces roughly balance each other, so the shape and diameter of the Earth remain constant.
What type of boundary would you observe subduction?
Convergent Plate Boundaries—Subduction Zones.
What is the definition of sea floor spreading?
: the divergence at mid-ocean ridges of the tectonic plates underlying the oceans that is due to upwelling from the earth’s interior of magma which solidifies and adds to the spreading plates.
What are the three types of subduction?
There are three types of convergent boundaries, and therefore, three types of subduction zones.
- Ocean-ocean boundaries, where two oceanic plates converge with each other.
- Ocean-continent boundaries, where an oceanic plate collides with a continental one.
- Continent-continent boundaries, where two continents collide.
What does subduction mean?
sub·duc·tion (ˌ)səb-ˈdək-shən. : the action or process in plate tectonics of the edge of one crustal plate descending below the edge of another.
What are the three types of plate boundaries and describe each type?
The three types of plate boundaries are divergent boundaries, wherein two plates diverge; convergent boundaries, where two plates meet; and transform boundary, where two plates slip sideways and move past each other. b. In the divergent boundary, the two plates move away from each other.
What type of plate boundary where subduction processes does not occur?
Figure 2.4. 6. At a convergent boundary with two plates of continental lithosphere, no subduction occurs, and a large mountain range forms with associated earthquakes.
What are the 4 types of boundaries?
Plate Boundaries and Hotspot Demonstration
- Divergent Plate Boundary. Volcanic eruptions and shallow earthquakes are common where plates rip apart.
- Convergent Plate Boundary.
- Transform Plate Boundary.
- Hotspot.
What are the 3 types of plate boundaries explain each?
What happens during seafloor spreading?
How do we know the seafloor is spreading?
Supporting Evidence for Seafloor Spreading
First, samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached, and the sediment cover is thinner near the ridge.