21 Jul 2019


Five Quakes Triggered on Opposite Side of the Pacific

from Chile Earthquake

These five, arguably triggered* quakes:

* OSU found seven quakes* in this belt centered on 160º where rates were nearly 50% higher than background, hence it is likely at least three to four of these seven quakes would not have ordinarily occurred in that time window, were most likely triggered.

* Two more are visible in the second image below, in central Asia.

The above five were placed according to this portion of the image Nature published:

..part of the area within 30º of the Chile quake’s antipode,   :

As pictured: Green ovals marking epicenters in OSU’s graphics
are represented by red X’s in this site’s illustrations.

The above image is an enlarged portion of this “a” panel:

. . of Figure 8 on this page of the Nature report.

There is a link on that page to the section of the report where it is discussed.

 – In this site’s experience, it is best to scroll upward about a page to the beginning of the section discussing these figures. –

Also noteworthy is the black oval circled orange in the previous image, representing another arguably triggered quake about 145º distant from the quake in Chile, plus an additional black oval circled in red in the above image about 140º distant in Indonesia (at bottom of 30º circles).*

How this site measured coordinates of the antipode and triggered quakes on these graphics is demonstrated on this page.

* The caption on Nature’s site indicates some such quakes were just beyond the three-day limit for inclusion in the counts, but whether these two occurred within three days or not, they at least illustrate quakes within about 35 to 40º of the antipode, where the second highest rate of triggering was observed. (Future research may also determine whether some triggered quakes take longer than three days to occur.)

Fine Detail: Several of the green dots in the six diagrams of potentially triggered quakes on the Nature page linked above have small black dots in the center, and a few of those seem to be two largely overlapping epicenters. This web site could find no mention of these in the article, but at least some seem as if an indication a second quake occurred at virtually if not the same location.