The image directly above is of the recent 7.8 magnitude earthquake that struck Fiji at 608km in depth on September 6, 2018 at 15:49UTC. Spectrogram and seismogram taken from station MCV within Long Valley caldera.
What is going on? Isn't it weird how once the Kilauea eruptions calmed there was a good sized spike in 6.0's, 7.0's, and even 8.0's?! Also alot of the earthquakes recently of larger magnitudes have occurred very deep, around 500-600km in depth. What is going on? I understand this happens time to time, but why the large spike in 7.0's and 8.0's at such a deep depth? Has something changed beneath our feet? And how much longer will this deep-focus sequence last?
The seismogram and spectrogram above shows the 7.8 in Fiji but this time from station MCID which resides within the WY network on the southwestern tip of Yellowstone National Park.
Deep-focus earthquakes, earthquakes that occur usually around 400km deep and deeper, are not that rare. However what is rare is large magnitude earthquakes, 7.0 and above, occurring 500km in depth or deeper. They do occur though, with around 30 or so 7.0 earthquakes occurring at that depth since around 1900. What is even more rare is a magnitude 8.0+ occurring around 500-600km in depth! You can see this in the two images directly below:
So the first of the two images directly above is the settings I input into the earthquake catalog. The second image is the result from the search.
From the year 1899 to today, there have only been four earthquakes magnitude 8.0 and above that have occurred 500km deep or deeper. One in 1970, one in 1994, one in 2013, and one in 2018. You can see they are rare! Of course 7.0's are also increasing as well. How come seismic activity around the globe was somewhat calm during the Kilauea eruptions? Isn't that weird?
The above two images show in the past two months, from July 6 to September 6, 2018, there have only been 5 earthquakes magnitude 6.0 and above that have occurred at 540km in depth or deeper, in the world. Now there have been a few other 7.0's since the Kilauea eruption stopped and many, many, many 6.0's. However they were not considered deep earthquakes. I am only focused on the deep-focus events right now. So how come earthquakes seem to be increasing in quantity, depth, and magnitude? Including a magnitude 8.2 and a 7.8 in the same location within just about a month at virtually the same depth? That is some hardcore activity! I feel bad for those who live on those islands near this area. Things really must be shaking! Please keep them in your prayers.
Now the last two images, directly above, shows all magnitudes for the Fiji area. In the past two months, from July 6 to September 6, 2018, there have been 36 earthquakes magnitude 0 and above that have occurred at 600km in depth or deeper. That is alot of deep activity! And this is just at Fiji! Let's hope it calms down. These deep-focus sequences seem to remind me of the deep earthquake activity we saw in the months leading up to the Kilauea eruptions. Once the eruptions started, seismic activity somewhat calmed globally during the entire eruption. Barely a 6.0 here and there, however magnitude 5's were still occurring near a normal rate, though slightly diminished. Now once the Kilauea eruptions calmed, BOOM! Many, many 6.0's and 7.0's. I don't know where this is heading, but its a very cool time to be alive if you are interested in earthquakes! If you require any data or webicorder images please goto "Contact". Thank you and God bless!
Ben Ferraiuolo is a fast learner and someone who will always stand for the truth. Visit "About Me" for more!