I was wondering how the sun spot activity could be a contributing factor. As sun spots can disrupt electronics, etc. could this activity also disrupt the earth’s magnetic field?
Short answer: No one's ever found anything that stands up to examination.
The data's out there - you could easily compare daily sunspot activity to the number of M5+ earthquakes reported on a daily basis, or even a monthly basis, and see if you can find a correlation in the data. It's been done, been discounted, and done again. When charted out, major seismic events are extremely random.
Thinking about it, here would be my plan if you wanted to examine to see if there was at least a correlation between sunspot (or lunar) activity and earthquakes... The two Christchurch earthquake events are extremely well detailed online, with aftershock listings laid out nicely - I'd pull those datasets and then pull the lunar or solar activity charts, and compare the two. An active aftershock region should demonstrate more clearly any actual causal connection. Pretty sure it'd come up blank too, but hey, if anything would show it, an already active and disrupted region should.
He said that lunar events affect the tides and gravity but the sun affects earthquakes (I think?)