I wouldn't doubt NASA when they say that Solar Flares can create level five to six earthquakes. I believe they are correct. Because about a week before the New Zealand Earthquake occurred, there were a few large solar flares recorded on the suns surface during that time period. The same applies to the recent Tsunami and earthquake that devastated Japan. The sun does affect, not only Earth's mantel, but also its tectonic plates, which in turn results in earthquakes. There is also a disruption of electrical conductivity within the earths atmosphere as well, during periods of high solar activity.