Thanks for posting this, I hope more people begin to take this seriously.
This isn't true and can be shown to be false. I will take the time to explain it here.
Two things that should be understood:
1. Magnetic instrumentation often responds to earthquakes because of something called preseismic lithosphere-atmosphere-ionosphere coupling. Electromagnetic disturbances have been noticed before earthquakes for centuries; LAI coupling has been observed for decades.
Electromagnetic disturbances before earthquakes (paper)
(VLF is the frequency range at which the HAARP magnetometer operates)Several observations were made of Very Low Frequency (VLF) emissions apparently associated with earthquakes, which were recorded independently at ground-based stations and on satellites. The observations at the Kerguelen station (49"26'S, 70°25'E) were made using magnetic antennae, on April 24 and 25, 1980, during a period when three earthquakes with magnitude Ms > 4.7 took place near the station. Several increases of electromagnetic waves at the time of earthquakes were recorded on the polar-orbiting satellite AUREOL-3. The observations on the geostationary GEOS-2 satellite were made using magnetic and electric antennae during the period 1977- 1981.
2. It is physically impossible for HAARP to cause an earthquake the size of the one in Japan. With electromagnetically induced seismicity (which is real - it is even noticed when larger generators start up), the energy released equals the energy put in. The earthquake released about 3.9×1022 joules. So assuming HAARP can operate at a maximum of 4 megawatts (its max is actually less), that means it would take 120,000,000,000 HAARPS to produce that amount of energy in 24 hours. That's a hundred and twenty billion. Even if it were powered by the world's biggest power plant, at about 20 GW, it would take 24,000,000 of them. There are only five known ionosphere stations: HAARP, HIPAS, Sura, EISCAT, and Arecibo.
Magical explanations of where the energy come from are also easy to show to be false. For example, resonance doesn't amplify energy or release hidden supplies of energy.
So as you can see, there is no reason to be alarmed at the HAARP magnetometer readings, and there is no way HAARP can induce such a large energy release. There are many other problems with the idea as well.