The newest, thinnest crust on Earth is located
near the center of mid-ocean ridge
—the actual site of seafloor spreading
Where on Earth is the youngest seafloor found?
Seafloor is youngest
near the mid-ocean ridges
and gets progressively older with distance from the ridge. Orange areas show the youngest seafloor. The oldest seafloor is near the edges of continents or deep sea trenches.
Where does New seafloor come from?
New seafloor is generated from
the upper mantle at the mid-oceanic ridges
, spreads laterally outward, and is eventually subducted, or consumed, at the margins of ocean basins. Subduction may also occur between two regions of oceanic crust, with older, denser sections underthrusting younger, less-dense ones.
Where can the newest and oldest crust be found in the ocean floor?
Explanation:
New ocean crust
is formed at the mid
ocean
ridges. The
new crust
is then pushed away from the ridge as
newer crust
comes
to
the surface. The
ocean crust
then spreads out enlarging the
ocean
.
How old would the oldest Seafloors be that we find on Earth?
Some cratons in Canada and Greenland shelter the oldest continental rocks in the world,
about 4 billion years old
.
Where are the oldest rocks found on Earth?
Bedrock along the northeast coast of Hudson Bay, Canada
, has the oldest rock on Earth. Canadian bedrock more than 4 billion years old may be the oldest known section of the Earth’s early crust.
Who discovered seafloor spreading?
Harry Hess
: One of the Discoverers of Seafloor Spreading.
What is the seafloor made of?
The seafloor contains deposits of minerals that we use in everyday life such as
copper, zinc, nickel, gold, silver, and phosphorus
. These deposits occur as crusts on volcanic and other rocks and as nodules on abyssal plain sediment that are typically about 3 to 10 centimeters (1 to 4 inches) in diameter.
What rock is the seafloor made of?
The oceanic crust is primarily composed of
mafic rocks, or sima
, which is rich in iron and magnesium.
What 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).
What is the world’s oldest ocean?
The Pacific
is the oldest of the existing ocean basins. Its oldest rocks have been dated at about 200 million years.
Why is no oceanic crust older than 200ma?
Most oceanic crust is less than 200 million years old, because
it is typically recycled back into the Earth’s mantle at subduction zones
(where two tectonic plates collide).
What is the oldest thing on Earth?
Microscopic grains of dead stars are the oldest known material on the planet — older than the moon, Earth and the solar system itself.
What is the oldest crystal on Earth?
The oldest pieces of rock on Earth,
zircon crystals
, may have formed in craters left by asteroid impacts early in the planet’s life. Zircon crystals are more than 4 billion years old.
What is oldest known mineral on Earth?
Zircons
, the oldest minerals on Earth, preserve robust records of chemical and isotopic characteristics of the rocks in which they form.
What are the 4 steps of seafloor spreading?
- Magma comes out of the rift valley.
- Magma cools to rock and hardens.
- Rock is pushed away as new rock is formed at MOR.
- Oceanic crust and continental crust meet at the trench.
- Oceanic crust bends down under the continental crust.
- Gravity pulls rock towards mantle.
- Rock melts to mantle.
