Seismic Review and Forecast for July 2017
Most Significant Quakes Have Been Absent
The month of June, like April and May, was average when it came to worldwide seismic activity (all those three months being a tad less than exactly average but still within the range of average). However, for the largest of earthquakes or those of at least 7.1 magnitude, there have been none for the past five months when normal would be averaging one per month. So, in that respect, things have been below average for the past few months.
If one looks at all earthquakes of at least 6.8 magnitude in a given month, June's numbers would be twice the average if we use the data from the USGS or, from my experience, if one uses the more precise source of the Global CMT Catalog (formerly the Harvard CMT Catalog), it would be at the level of the expected average. The later source is what I use for the table below which gives a comparison of activity for the past six months.
Latest Seismic Review
The month of June started off about as I had forecast. I was looking for earthquakes of at least 6.8 magnitude and numbering a bit above average (say three instead of the usual two). My standard source gave the occurrence of a 6.7 magnitude (6.8 per the USGS) a few hours into my first seismic window for the month (on June 2nd). I had set the probability for such a significant event at 65% above the expected average. There followed a 6.4 magnitude earthquake on the 12th of June in the Aegean Sea in the border region between Greece and Turkey. Five hours shy of two days later there was the largest earthquake of the month, a 7.0 magnitude event in Guatemala near the Mexican border (other sources give this as a 6.8 or 6.9 magnitude event). Since it was over 70 km deep, it did not do any significant damage in the area. Both of those earthquakes fell within a third forecast window which I had determined had a 55% chance above the expected average of at least one 6.8 magnitude earthquake occurring.
Eight days and five hours after this last earthquake (on 22 June at 1231 UT), a second quake of nearly the same magnitude of 6.8 occurred in the same general area of Guatemala. This time the depth of the quake was less than 40 km, so there was a bit more shaking than before. This earthquake would be considered the second in a series, but was too large to be considered a typical aftershock. It occurred 11.5 hours before a 1.5 day window opened that I had forecast had a 70% chance above average of such an earthquake occurring. In retrospect I realized, since the Astro-Aspect Values (or AAVs) for the time of this quake was above the average level for the month, that I should have started the window at least half of a day earlier than I did. A day after this window ended, I had projected another 2.5 day window with a 85% probability of a 6.8 magnitude or larger earthquake occurring. No such earthquake happened. My results for the month were thus a bit mixed, but I feel that the outcome was not too disappointing.
Latest Seismic Forecast
In the past I have written articles relating increased significant earthquake activity to particular dates during any year. One of those times is around July 9 to 10. This year that date has a noteworthy peak of AAVs so I am expecting an elevated chance of a significant seismic event occurring around that time. There is also elevated AAV levels later in the month and, as a result, I expect an increased chance of similar activity to occur from July 18 through the 30th (especially the 19th and the 26th-27th). Another internet forecaster of seismic events, who uses different methods than myself, also forecasts an increased chance for large earthquakes during the 27th-30th of the month. His name is Frank Hoogerbeets, who resides in the Netherlands and features regular seismic forecasts on his ditrianum website.
One last window is present during the first two days of July 2017 and I would not be surprised if a significant seismic event occurs during that time. Mr. Hoogerbeets also sees a strong possibility of large earthquakes during this time. He feels that a magnitude 8 or larger earthquake is possible during early and late July, but my feeling is that the possible range would be from 6.8 to 7.8 in magnitude.
Related to an eclipse which occurred on 9 March 2016, there is an elevated risk of a large quake in the Indonesia area during the early July window and also on or near the dates of the 11th, 27th and 29th of July. This same eclipse, along with elevated AAVs related to asteroids, also increases the chances of an earthquake on or near the 16th of August. There is also an increased chance of a significant earthquake in Africa during the month of July. The dates to watch for that possibility are the 11th and 31st of July, in relation to a 3 November 2013 eclipse, and the 21st and 29th of July, in relation to a 1 September 2016 eclipse. More than half of the month is covered by seismic windows (18.5 out of 31 days or 60%), so in theory it should be seismically more active than any of the previous five months.
© 2017 Joseph Ritrovato