Magnetic signals from tsunamis & eruptions

Earth's salty oceans are electrically conductive fluid passing through Earth's variable main magnetic field-- so they induce electric currents and magnetic fields of their own. Marine magnetic fields depend on the given ocean flow's transport and electrical conductivity. All forms of ocean flow induce magnetic fields-- including the flow caused by tsunamis. Tsunamis can be created by submarine earthquakes, landslides, or volcanic eruptions. The magnetic fields induced by tsunamis can be used to better understand the geophysical processes creating tsunamis, as well as to improve our tsunami hazard warning systems.