How does seafloor spreading account for the age of the seafloor?
New, young sea floor is continually being formed by basalt eruptions at the ridge crest
. … Thus, old sea floor is continually being destroyed at trenches, while new sea floor is being formed at the ridge crest.
How does the age of the ocean floor provide evidence for seafloor spreading?
Abundant evidence supports the major contentions of the seafloor-spreading theory. 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.
What is seafloor spreading and what does it do to the ocean floor?
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.
What is the pattern of seafloor age in the ocean floor?
The age pattern is
symmetric
. Youngest ages are at the middle of the pattern (on the oceanic ridges) and the seafloor grows older moving outwards to each side of the middle.
How does the rate of seafloor spreading affect sea level?
The increased rate of seafloor spreading caused
sea level to rise
. Increasing the rate of seafloor spreading inflates the ridge. Hot, young lithosphere is forming and moving away from the ridge at a faster rate and moves a greater distance from the ridge before it cools and contracts. … So sea level rises.
What is sea floor spreading and what causes it?
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. Eventually, the crust cracks.
What is the importance of seafloor spreading?
Seafloor spreading proves that
the ocean itself is a site of tectonic activity
. Seafloor spreading is just one part of plate tectonics. Subduction is another. Subduction happens where tectonic plates crash into each other instead of spreading apart.
What boundaries destroy sea floor?
The seafloor is destroyed at
a COnvergent Boundary
.
Which is the youngest ocean?
Indian Ocean
, body of salt water covering approximately one-fifth of the total ocean area of the world. It is the smallest, geologically youngest, and physically most complex of the world’s three major oceans (Pacific, Atlantic, and Indian).
Why is the floor of the Atlantic Ocean older at the edges?
As
the mantle rises towards the surface below the ridge the pressure is lowered (decompression) and the hot rock starts to partially melt
. … This process is known as “sea floor spreading
Where is the seafloor spreading the fastest?
Some of our recent research involves hydrothermal and structural investigations along Earth’s fastest seafloor spreading center, the 28°S–32°S East Pacific Rise
What is the rate of seafloor spreading?
It spreads
about 6-16 centimeters (3-6 inches) every year
. There is not an ocean trench at the East Pacific Rise, because the seafloor spreading is too rapid for one to develop!
Why is Earth not growing in spite of seafloor spreading?
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
. … Deep below the Earth’s surface, subduction causes partial melting of both the ocean crust
What are the three types of seafloor spreading?
There are three types of plate-plate interactions based upon relative motion: convergent, where plates collide,
divergent
, where plates separate, and transform motion, where plates simply slide past each other.
What causes change in the sea floor?
The seafloor changes because
of the earth plates moving causing magma to spew in the water
. The magma is then pushed outward causing the seafloor to move and change.
Who discovered the sea floor spreading?
Harry Hess
