What was the maximum age of the seafloor?

What was the maximum age of the seafloor?

150 million years

What did Harry Hess discover about the ocean floor?

Hess discovered that the oceans were shallower in the middle and identified the presence of Mid Ocean Ridges, raised above the surrounding generally flat sea floor (abyssal plain) by as much as 1.5 km.

What supports the theory of 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 did Scientist discover at the bottom of the ocean?

Life is found near deep ocean vents In 1977 scientists discovered that at the deepest parts of the ocean, which people had long imagined to be dark, cold, and lifeless, was a strange environment teeming with life.

What are the three steps in the process of sea-floor spreading?

Terms in this set (7)

1. Magma comes out of the rift valley.
2. Magma cools to rock and hardens.
3. Rock is pushed away as new rock is formed at MOR.
4. Oceanic crust and continental crust meet at the trench.
5. Oceanic crust bends down under the continental crust.
6. Gravity pulls rock towards mantle.
7. Rock melts to mantle.

What is the second step in the process of seafloor spreading?

Who proposed seafloor spreading?

Harry Hess

What was probably the first evidence that led?

Alfred Wegener is credited with developing the continental drift hypothesis. What was probably the first evidence that led some to suspect the continents were once connected? The puzzle-like fit of the continents, especially Africa and South America.

How do you prove faulting has occurred?

ANSWER: A geologist could prove that faulting has occurred by examining the rock. The sedimentary rock layers on either side of the fault-line have been displaced vertically with respect to one another.

What process recycles the crust?

Crustal recycling is a tectonic process by which surface material from the lithosphere is recycled into the mantle by subduction erosion or delamination.

How is crust destroyed?

Just as oceanic crust is formed at mid-ocean ridges, it is destroyed in subduction zones. Subduction is the important geologic process in which a tectonic plate made of dense lithospheric material melts or falls below a plate made of less-dense lithosphere at a convergent plate boundary.