Quick Answer: What Are The Steps Of Seafloor Spreading?

What is the first step of seafloor spreading quizlet?

1.

A long crack in the oceanic crust forms at a mid ocean ridge.

2.

Molten material rises and erupts along the ridge..

What is the first step of seafloor spreading?

Also Know, what is the first step of seafloor spreading quizlet? Sea-Floor Spreading begins at a mid-ocean ridge, which forms along a crack in the oceanic crust. along the ridge, molten material that forms several kilometers beneath the surface rises and erupts.

What is the importance of seafloor spreading?

Significance. Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in the lithosphere.

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 is seafloor spreading and how does it work?

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.

Where is active seafloor spreading occurring today?

Where is active sea floor spreading occurring today? Seafloor spreading is the movement of old rock that is being pushed by the new young oceanic crust. This would be a divergent since the plates are separating from each other. Active seafloor spreading is occurring at mid-ocean ridges.

What is the major evidence that seafloor spreading creates new lithosphere?

When the Earth’s magnetic field reverses, the magnetized minerals align in the opposite direction. The record of magnetic reversals is carried away from each side of the spreading center of a mid-ocean ridge, showing that the molten rock is creating new lithosphere.

What is seafloor spreading theory?

Seafloor spreading, theory that oceanic crust forms along submarine mountain zones, known collectively as the mid-ocean ridge system, and spreads out laterally away from them. …

Where does seafloor spreading occur?

Seafloor spreading occurs along mid-ocean ridges—large mountain ranges rising from the ocean floor. The Mid-Atlantic Ridge, for instance, separates the North American plate from the Eurasian plate, and the South American plate from the African plate.

What causes the plates to move?

The plates can be thought of like pieces of a cracked shell that rest on the hot, molten rock of Earth’s mantle and fit snugly against one another. The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other.

How old is the seafloor?

150 million yearsVery little of the sea floor is older than 150 million years. This is because the oldest sea floor is subducted under other plates and replaces by new surfaces. The tectonic plates are constantly in motion and new surfaces are always being created.

What is the average speed of seafloor spreading?

approximately 5 centimeters a yearThe average speed of seafloor spreading is approximately 5 centimeters a year. This growth rate can be compared to the growth rate of human fingernails (Krupicka). The global ridge system consists of oceanic ridges. Seafloor spreading occurs at these elevated oceanic ridges and has high heat flow and volcanism.

What is the difference between continental drift and seafloor spreading?

Continental drift is a very similar process to seafloor spreading. Continental drift is the gradual movement of continental plates over the Earth’s surface over time. … Seafloor spreading is the formation of new areas of oceanic crust due to the upwelling of magma as oceanic aparts pull apart.

Who proposed seafloor spreading?

Harry HessHarry Hess was a geologist and Navy submarine commander during World War II. Part of his mission had been to study the deepest parts of the ocean floor. In 1946 he had discovered that hundreds of flat-topped mountains, perhaps sunken islands, shape the Pacific floor.

What boundaries can destroy seafloor?

At convergent plate boundaries, oceanic crust is often forced down into the mantle where it begins to melt. Magma rises into and through the other plate, solidifying into granite, the rock that makes up the continents. Thus, at convergent boundaries, continental crust is created and oceanic crust is destroyed.