Earth’s magnetospehere is frequently bombarded with solar flares from the Sun, resulting in geomagnetic storms and visually stunning aurorae.
Leaks have more recently been detected to occur in Earth’s magnetic field, which interact with solar storms and have been known to cause large-scale electrical blackouts and disruptions to satellites orbiting Earth.
In addition to variations resulting from solar flares from the Sun, magnetometers located around Earth regularly detect magnetic field deviations caused by geological structures and anomalies on the surface. These variations may be caused by geophysical properties of iron artifacts, stone structures and ditches.
Basalt, an iron-rich volcanic rock on the ocean floor contains large quantities of magnetite, the most magnetic naturally occurring mineral on Earth. Icelandic mariners in as far back as the 18th century recognized the basalt distorting their compass readings.
