Question: What Is Meant By Seafloor Spreading?

What causes the plate 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..

What is the significance of the 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 another word for seafloor spreading?

The definition of sea-floor spreading in the dictionary is a series of processes in which new oceanic lithosphere is created at oceanic ridges, spreads away from the ridges, and returns to the earth’s interior along subduction zones Also called: ocean floor spreading.

What are the steps in the process of seafloor spreading?

What are the steps in the process of sea floor 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.

What is the source of magma for seafloor spreading?

Sea-floor spreading — In the early 1960s, Princeton geologist Harry Hess proposed the hypothesis of sea-floor spreading, in which basaltic magma from the mantle rises to create new ocean floor 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.

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 boundaries 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.

Where is seafloor destroyed?

You are correct that the seafloor is destroyed at subduction zones, but it is simultaneously being created at mid-ocean ridges. see figure 1 . Figure 1: Seafloor spreading at a mid-ocean ridge(where new crust is being created) and it’s destruction at a subduction zone.

Where is the oldest seafloor found?

Mediterranean SeaThe oldest seafloor is comparatively very young, approximately 280 million years old. It is found in the Mediterranean Sea and is a remnant of an ancient ocean that is disappearing between Africa and Europe.

What is seafloor spreading simple?

Seafloor spreading happens at the bottom of an ocean as tectonic plates move apart. The seafloor moves and carries continents with it. … At the Mid-Atlantic Ridge (and other places), material from the upper mantle rises through the faults between oceanic plates. It forms new crust as the plates move away from each other.

How was seafloor spreading discovered?

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. … This created new seafloor which then spread away from the ridge in both directions.

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 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.