what is the evidence of seafloor spreading

Seafloor spreading is the process by which new oceanic lithosphere forms at mid-ocean ridges. As tectonic plates move away from each other, magma rises from Earth’s interior. It then cools and solidifies in the center of the ridge. The rising magma pushes up between the plates and drives them further apart.

Why magma rises in the ridge?

Beneath a typical mid-ocean ridge, mantle material partially melts as it rises in response to reduced pressure. This melted rock, or “magma”, may collect in a reservoir a few kilometers below the seafloor, awaiting eruption. … When magma pressure builds up enough to force its way out to the seafloor, eruption occurs.

How do magnetic stripes on the ocean floor serve as evidence for seafloor spreading quizlet?

How do strips of magnetized rock on the ocean floor provide evidence of sea-floor spreading? Strips of ocean-floor basalt record the polarity of Earth’s magnetic field at the time the rock formed. … The pattern shows that ocean floor forms along mid-ocean ridges and then moves away from the ridge.

Which statement accurately describes how magnetic stripes in ocean rock provide evidence of seafloor spreading?

Which statement accurately describes how magnetic stripes in ocean rock provide evidence of seafloor spreading? C. The pattern of magnetic strips shows that the seafloor is expanding at mid-ocean ridges.

What is the first step in the seafloor spreading process?

1. A long crack in the oceanic crust forms at a mid ocean ridge. 2. Molten material rises and erupts along the ridge.

What are the 3 types of evidence for seafloor spreading?

What three types of evidence provided support for the 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.

What evidence do scientist use to determine where the edges of the plates are located?

By plotting the locations of earthquakes, scientists have not only been able to locate plate boundaries but have also been able to determine plate characteristics and predict the movement of the plates. In this investigation, you will plot the locations of earthquakes and determine the boundaries of the earth’s plates.

How does paleomagnetic evidence support the theory that continents change position over time?

Because the magnetism of a rock is frozen into the rock at the time of its formation, the paleomagnetic poles do not move relative to the continent, and therefore, they must be moved with the continent. The continents are moved along with their paleomagnetic pole to their predrift positions.