| Ultimately, the occurrence of reversals must be related to changes in the fluid flow in the outer core. |
| It is probable that every naturally occurring element is present in the outer core at least at trace levels. |
| The simplest explanation is that convection in the outer core ceases, allowing the magnetic field to decay. |
| The outer core is thought to be liquid because shear waves do not pass through it. |
| Primary waves are slowed and deflected but not stopped by the liquid outer core. |
| As long as there is sufficient fluid motion in the outer core, the process will continue. |
