In a recent issue of the Journal of Geophysical Research, physicist Friedemann Freund theorizes that positive charges can be generated when huge stresses are generated along faults in the Earth's crust. The rocks in the crust normally act as insulators that conduct electrical charges only poorly. But under the severe stress generated before an earthquake, these rocks may behave briefly like "p-type semiconductors" found in computer chips, capable of releasing large numbers of positive charges referred to as "holes."
These charges speed upward toward the surface of the Earth at between 220 and 660 mph.
Freund, a professor at San Jose State University in California, thinks they ionize the atmosphere upon reaching the air, accounting for the bizarre effects -- radio interference and colored streamers, flashes and glows reported by thousands of observers. Among them:
Radio interference reported in the days before the worst quake recorded (magnitude 9.5), in Chile in 1961, as well as Alaska's magnitude 9.2 Good Friday quake in 1964.