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What causes the seafloor to spread apart?

Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor.

Why are magnetic bands in the eastern Pacific Ocean so far apart compared to the magnetic bands along the mid Atlantic Ridge?

BOTH SEDIMENT THICKNESS AND THE AGES OF OCEAN-FLOOR ROCKS INCREASE WITH DISTANCE FROM THE RIDGE. MAGNETIC BANDS IN THE EASTERN PACIFIC OCEAN ARE FARTHER APART THAN BANDS ALONG THE MID-ATLANTIC RIDGE BECAUSE THE RATES OF SPREADING IN THE PACIFIC OCEAN ARE FASTER THAN THOSE IN THE ATLANTIC OCEAN.

Why are magnetic stripes on the seafloor parallel?

They are parallel because each magnetic stripe represents crust that formed and magnetized at a mid-ocean ridge during a period of either normal or reversed polarity.

Which magnetic stripe is the oldest How do you know?

The north pole becomes the south pole, and the south pole becomes the north pole. Rocks of normal and reversed polarity are found in stripes symmetrically about the mid-ocean ridge axis. The seafloor is youngest at the ridge crest and oldest far away from the ridge crest.

How does magnetic stripes happen?

The striped magnetic pattern develops because, as oceanic crust pulls apart, magma rises to the surface at mid-ocean ridges and spills out to create new bands of ocean floor. Later, after the planet’s magnetic field flips again, the next stripe of new ocean floor aligns its polarity in the opposite direction.

Where are magnetic stripes found?

In most magnetic stripe cards, the magnetic stripe is contained in a plastic-like film. The magnetic stripe is located 0.223 inches (5.66 mm) from the edge of the card, and is 0.375 inches (9.52 mm) wide. The magnetic stripe contains three tracks, each 0.110 inches (2.79 mm) wide.

What causes magnetic stripes on the seafloor quizlet?

The magnetic properties of minerals found in magma align themselves according to earths magnetic polarity. Over time the magnetic poles reverse and the alignment of the minerals reverse too. These stripes are the same on either side of the ridge. New crust is created, plates move away from each other.

What happens to the seafloor rocks after it enters they a trench?

The older rock moves outward on both sides of the ridge as new rock forms in the center of the ridge from cooling of molten material. This process is sea floor spreading. Instead, the ocean floor plunges into deep underwater canyons called deep-ocean trenches. At a deep-ocean trench, the oceanic crust bends downward.

What is the difference between seafloor spreading and continental drift?

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.