From outer space, NASA and other researchers are reporting thermo anomalies prior to large earthquakes and reasons to understand earthquake lights at the same time. And what of the cause for ear tones? I'll let you decide. Here are excerpts from three documents with links provided so you can read all of the information. Maybe we are closer than we realize...Petra

In one laboratory experiment, Freund and colleagues placed red granite blocks under a 1,500 ton press - mimicking in some ways what happens miles below Earth's surface. A sensitive camera developed at JPL and GSFC monitored the rock and detected infrared emissions. Furthermore, a voltage built up on the rock's surface. This leads Freund to believe the cause might be electrical.

Ordinary rocks are insulators. Rocks placed under great stress, however, sometimes act like semiconductors. Freund believes that, before a quake, pairs of positive charges called 'defect electrons' or 'positive holes' split up and migrate to the surface of stressed rocks. There they recombine with each other and, in the process, release infrared radiation. This explanation has some support from experiments, but it's still a young theory that hasn't gained widespread acceptance among scientists, he notes.

http://www.firstscience.com/SITE/ARTICLES/earthquake.asp

To test this, Freund applied sudden, short stresses to rocks by shooting them with a crossbow and with NASA's Ames Vertical Gun Range, a two-stage, light-gas gun that can accelerate 0.25-in. projectiles to velocities of approximately 6.5 km/s. The impacts with the crossbow projectiles created small but intense deformations at the impact points and freed a cloud of electric charges that had existed in the rocks in an electrically inactive, dormant state. The charge clouds propagated at several hundred meters per second, even speeding through portions of the rocks that had not experienced stress.
There were also some high-frequency components, in the range of radio frequencies, which probably arise from the buildup of electric fields at the rock surface; in particular, at the corners and edges. These local fields are so high that they can produce corona discharges accompanied by visible light.

http://www.photonics.com/spectra/applications/XQ/ASP/aoaid.346/QX/read.htm

Two currents, which are coupled through their electric fields, represent a system that can go into oscillations [Freund et al., 2002b]. A predictable consequence of the waxing and waning of currents in the Earth's crust is the emission of low to very low frequency electromagnetic radiation, possibly in a pulsating mode. When p-hole clouds reach the Earth's surface, they lead to a plethora of phenomena. Being carriers of positive charge, p-holes are expected to change the ground potential. A need for high positive ground potentials has been inferred from studies of pre-earthquake ionospheric perturbations [Liu et al., 2000]. Another predictable effect is the build-up of high electric fields at the rock-to-air interface – so high that we need to consider the possibility (i) of field-ionization of air molecules and emission of positive ions into the atmosphere close to ground, and (ii) of dielectric breakdown of the air and corona discharges. Small air ions will act as nucleation centers for fog and haze, providing a possible explanation for the reported occurrences of pre-earthquake "ground-hugging fog". Air-borne positive ions could provide a explanation for strange pre-earthquake animal behavior, reported for centuries [Tributsch, 1983]. Corona discharges could be the cause of luminous phenomena, so-called "earthquake lights" [Derr, 1986; St- Laurent, 2000]. In addition, corona discharges could be the cause of static at KHz frequencies reported by radio operators [Warwick et al., 1982].

http://www.guidasicilia.it/ita/main/news/speciali/freund_nasa.htm