As I understand the situation, only very strong geomagnetic and solar storms are likely to trigger seismic activity. This activity often follows the geomagnetic or solar storms by 4-6 days. The earthquake today in California followed the strong storms of Oct 24-27 by about 4-5 days. If there is a relationship it is probably with those storms not a small M-class solar flare today.

The geomagnetic storm was one of the two strongest this year and occurred while Italy and Lake Tanganyika were both anti-solar. The strongest portions of geomagnetic storms occur in regions which are antisolar and sub-solar at the time of the initiation of the storm and stronger triggering effects are likely in these areas. Volcanism often follows geomagnetic storms in these areas, and the current very strong eruption of Mt. Etna which began on OCt. 26 (Saturday) is an excellent example. Mt. Etna was anti-solar at the time of the storm initiation.