Why Seafloor Spreading Is Like A Moving Conveyor Belt?

What causes seafloor spreading quizlet?

During sea-floor spreading, magma erupts along a mid-ocean ridge to form new oceanic lithosphere.

The floor then moves away from the ridge, often toward a trench at the edge of the ocean basin.

These strips form a pattern that is the same on both sides of the mid-ocean ridge..

Which is the source of new material during the process of seafloor spreading?

Sea-Floor Spreading: The process by which new material is added to the seafloor. The material comes from volcanoes on the mid-ocean ridge. underwater volcanoes that hardens quickly in the water into rounded shapes. from the mid-ocean ridge, the older the rock is.

What are the main features of the deep seafloor?

Features of the ocean include the continental shelf, slope, and rise. The ocean floor is called the abyssal plain. Below the ocean floor, there are a few small deeper areas called ocean trenches. Features rising up from the ocean floor include seamounts, volcanic islands and the mid-oceanic ridges and rises.

How does the seafloor change as you move away from the mid ocean ridge?

Mid-ocean ridges and seafloor spreading can also influence sea levels. As oceanic crust moves away from the shallow mid-ocean ridges, it cools and sinks as it becomes more dense. This increases the volume of the ocean basin and decreases the sea level.

What are the steps in 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 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 happens to the seafloor at trenches?

Trenches are formed by subduction, a geophysical process in which two or more of Earth’s tectonic plates converge and the older, denser plate is pushed beneath the lighter plate and deep into the mantle, causing the seafloor and outermost crust (the lithosphere) to bend and form a steep, V-shaped depression.

How ocean floor rocks and sediments are evidence of seafloor spreading?

seafloor spreading: Supporting Evidence for Seafloor Spreading. … 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 happens after seafloor spreading?

Basalt cools to form a new crust near the mid-ocean rift. Old crust moves closer together. New crust moves away from the mid-ocean rift.

What is the evidence of seafloor spreading?

Several types of evidence supported Hess’s theory of sea-floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves. This evidence led scientists to look again at Wegener’s hypothesis of continental drift.

Who discovered 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.

How does seafloor spreading support the theory that continents move?

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. … At a spreading center, basaltic magma rises up the fractures and cools on the ocean floor to form new seabed.

What causes the seafloor to move?

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.

How do seafloor spreading and subduction work together?

As subduction occurs, crust closer to a mid-ocean ridge moves away from the ridge and toward a deep-ocean trench. Sea-floor spreading and subduction work together. They move the ocean floor as if it were on a giant conveyor belt. … In the process of subduction, oceanic crust sinks down beneath the trench into the mantle.

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.