Evidence has been mounting that it might be possible to detect earthquakes by measuring the changes in the ionosphere.
The RF-Seismograph team has been collaborating with Earthquakes Canada to find a correlation between HF propagation and earthquakes. There was a distinct event that occurred on Nov 1st (M5.0 off the coast of Vancouver Island) which was detected by the RF-Seismograph. The team is in the process of correlating earthquakes that are bigger than M6.0 into the 4 years of data that they have accumulated.
The presentation can be found belowRF-Seismograph detects Earthquakes Markup