Quick Answer: What Causes Magnetic Striping?

What is magnetic striping?

Magnetic Striping is when the sea floor is spreading, and magma from the mantle is rising through the Earth’s crust.

That magma then turns into new crust, forming the “Oceanic Crust”..

What does the alternating magnetic striping suggest?

A polarity reversal means that the magnetic North flips to where we know the South Pole is. … This creates a symmetrical pattern of magnetic stripes of opposite polarity on either side of mid-ocean ridges. These patterns of stripes provide the history of seafloor spreading.

What does magnetic striping tell us about the age of rocks?

Scientists can determine the age of the seafloor thanks to the changing magnetic field of our planet. … While it cools down, it records the magnetic field during its formation. The two parts of the oceanic plate are pulled apart, and magnetic stripes become older as they move away from the mid-ocean ridge.

How is magnetic striping linked to seafloor spreading?

At spreading centres, this crust is separated into parallel bands of rock by successive waves of emergent magma. When Earth’s geomagnetic field undergoes a reversal, the change in polarity is recorded in the magma, which contributes to the alternating pattern of magnetic striping on the seafloor.

Who discovered magnetic striping?

Vine and Matthews noticed there was a symmetrical pattern of magnetic stripes on either side of the mid ocean ridges. In addition when the basalts of the sea floor were dated, they were found to be the same age at similar distances away from the ridge on each side.

Where is the youngest material in the seafloor found?

The youngest crust of the ocean floor can be found near the seafloor spreading centers or mid-ocean ridges. As the plates split apart, magma rises from below the Earth’s surface to fill in the empty void.

Where is the youngest seafloor?

Seafloor is youngest near the mid-ocean ridges and gets progressively older with distance from the ridge. Orange areas show the youngest seafloor. The oldest seafloor is near the edges of continents or deep sea trenches.

How do we know the seafloor is spreading?

The magnetism of mid-ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. … Oceanic crust slowly moves away from mid-ocean ridges and sites of seafloor spreading. As it moves, it becomes cooler, more dense, and more thick.

Where does magnetic striping occur?

At spreading centres, this crust is separated into parallel bands of rock by successive waves of emergent magma. When Earth’s geomagnetic field undergoes a reversal, the change in polarity is recorded in the magma, which contributes to the alternating pattern of magnetic striping on the seafloor.

How is magnetic striping evidence of plate tectonics?

During times of normal magnetic polarity, the rocks being created stayed normal. … If they were created during times of reverse polarity, the rocks would freeze that magnetic orientation in place.

What is magnetic striping of the ocean floor?

Magnetic striping – Magnetic minerals are found in rocks. … But once the magma solidifies, the minerals are locked into place and as such can record the reversals of Earth’s magnetic field. The result of this is stripes of magnetic minerals that parallel the mid-ocean ridges.

Where does seafloor spreading happen?

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.

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 are magnetic anomalies on the ocean floor?

study of oceanic crust A marine magnetic anomaly is a variation in strength of Earth’s magnetic field caused by magnetism in rocks of the ocean floor. Marine magnetic anomalies typically represent 1 percent of the total geomagnetic field strength.

What is the orientation of the magnetic stripes of iron?

Magnetic Stripe Evidence Iron is attracted to the Earth’s magnetic North Pole and prefers to line up with Earth’s magnetic field. While lava is liquid, the bits of iron will tend to line up with a magnetic orientation pointing at the North Pole.