A private organization known as The Council of the National Seismic System, working out of Berkeley, CA, provides earthquake data and answers questions at their web site. A Troubled Times member reports:
The search parameters to use are:
catalog = CNSS
start time = yyyy/mm/dd,hh:mm:ss
end time = yyyy/mm/dd,hh:mm:ss
minimum magnitude = 3.0
maximum magnitude = 10
minimum depth = 550
maximum depth = 700
event_type = E
Using the data for quakes only 650 to 700 km, they happened more significantly more in the May to September time frame than in the October to April time - the summer months which the Zeta claim may be the arrival, and the time on the other side of the sun where Marduk is reported to arrive. I have looked at earthquakes in the range of 550 to 650 km, which is in what is called the transition area of the Mantle. From what I've been able to read so far, this is the area that would separate from the crust as the inner core realigns itself magnetically.
I've looked at the data on this back to 1963 to 36 years. I don't give a damn about Richter Scale since at that depth they rarely show more than 4 to 5 on the Richter Scale, and also since they are almost invariably in the mid Pacific in the neighborhood of the 180 longitude somewhere around -20 latitude to +20 latitude, this is apparently the weakest point in the crust at this time. I've not compiled the data on this part, but it appears that the longitude is starting to spread out beyond the -177 to +177 longitude. I believe this is significant, and should indicate that the break with the crust is loosening on a gradually wider arena, but this is only a suggestion at this point.
Here's the total for 1985 - 1996 quakes per year in the 550-650 km deep range:
Since the Zetas suggest that the event is in the northern region's summer, one might expect that this would be the time when the earth quakes are greater. This is exactly the case. Quakes are 1/3, greater 85-94, in the April to September time as opposed to the October to March time. This accelerates big time after 1994.
Compilation offered by Eric.