What is the orientation of the magnetic stripes of iron contained in rocks that support the idea of seafloor spreading?
Answers
Answer:
When magma rises in the divergent boundary, as new crust is formed, the iron minerals in the magma align themselves with the earth's magnetic field before the magma cools to rock. Iron minerals have a ferromagnetic property about them. This is why the rocks layers in the sea floor spreading have bands.
[I hope help]
Answer:
Evidence for Sea-Floor 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.
Evidence From Magnetic Stripes
When scientists studied patterns in the rocks of the ocean floor, they found more support for sea-floor spreading. You read earlier that Earth behaves like a giant magnet, with a north pole and a south pole. Surprisingly, Earth’s magnetic poles have reversed themselves many times during Earth’s history. The last reversal happened 780,000 years ago. If the magnetic poles suddenly reversed themselves today, you would find that your compass needle points south.
Scientists discovered that the rock that makes up the ocean floor lies in a pattern of magnetized “stripes.” These stripes hold a record of reversals in Earth’s magnetic field. The rock of the ocean floor contains iron. The rock began as molten material that cooled and hardened. As the rock cooled, the iron bits inside lined up in the direction of Earth’s magnetic poles. This locked the iron bits in place, giving the rocks a permanent “magnetic memory.”