noirxgrace t1_jdu9ilh wrote on March 27, 2023 at 6:21 AM

Reply to comment by wazoheat in Around 550 million years ago the earth's magnetic field almost collapsed, but then strengthened a few million years later. Scientists say this may have been due to the formation of the inner core. But why exactly would that cause the magnetic field to get stronger? by somethingX

I remember reading about the same. Since lava's temperature is well above above the Curie temperature of magnetite(800^(o)C), and it cools down, the orientation of the magnetite particles are all aligned and proportional to the ambient magnetic field, which makes it ferromagnetic.