Rocks become magnetic when(1 point)

Question

Responses

rocks are heated to extreme temperatures.
rocks are heated to extreme temperatures.
Earth's magnetic field reverses direction.
Earth's magnetic field reverses direction.
iron particles within the rock align with Earth's magnetic field.
iron particles within the rock align with Earth's magnetic field.
continents move.

Answer 1

Rocks become magnetic when:

iron particles within the rock align with Earth's magnetic field.

This process often occurs as rocks cool from a molten state. As the temperature drops below the Curie point (the temperature at which certain materials lose their permanent magnetic properties), the iron particles within the rock can become magnetized in alignment with the ambient magnetic field, which is usually the Earth's magnetic field. This can also occur in sedimentary rocks as iron-rich particles align before the sediment is compacted and solidified.