If you would like to begin a dialogue. I will offer the first salvo. You stated that the entire
earth should be affected by a proton storm, presumably this means that even if there
were an effect on seismicity it could not be localized.
The effects of geomagnetic (and proton storms) are not felt everywhere over the
earth equally, however. When a stream of particles from the sun encounters the
earth's geomagnetic shield, they spiral along lines of force towards the geomagnetic
poles. In a polar absorption event as we just had, a large stream of particles actually
hit the earth near the geomagnetic poles.
Compression of the ionosphere on the sub-solar regions and rarefaction on the
anti-solar regions can have a strong effect on the troposphere and an resulting
wind and weather patterns which are related to the upper atmosphere. It can be
argued that these in turn may affect rotational velocity of the earth (as evidenced
by Length of Day changes at the time of geomagnetic and proton storms). As
I have noted in another post, if the earth is accelerating, as it does during such
storms, there is a differential motion between the crust and the mantle because
the transfer of rotational energy must be taking place through drag between
the two.
Another effect which occurs during geomagnetic storms is the induction of
currents in conductors on the earth. These currents can be quite powerful and
tend to form under the electrojets, which are streams of electrons in the ionosphere
which are greatly enhanced in the few days following electron enhancements
from the solar wind. Such electrojets form around the geomagnetic equators
in the auroral regions, and over the geomagnetic equator. These induced
telluric currents can be quite powerful, enough to black out entire electrical grids,
as in the case of southeastern Canada in March 1989. Any conductor in the
earth, including waterways, underground water, or ore bodies or veins can
have strong currents formed within them from this effect which is quite well
documented.
The point is that effects from such storms do exist in the earth and are
not spread out, but localized around geomagnetic equator, poles and sub-
and anti-solar regions. The effects are consistent with the possibility of
triggering by electrical charging. A well-known geophysicist (who is currently
working on a paper with a number of colleagues) has calculated that charging
of water in crack tips has the potential to increase the pressure by one
to two bars at the levels seen in telluric currents available during strong
geomagnetic storms. This is quite sufficient to trigger crack breakage and
eventual rupture.
Also, it should be noted that experiments have been published that show
that electrification at low levels of a surface where water is present can reduce
friction and increase the likelihood of slippage along that surface with another
surface by several orders of magnitude.