Possibility of Nankai Trough giant earthquake "No special changes observed" Study meeting June 5 19:33
The regular study group, which evaluates the possibility of a huge earthquake in the Nankai Trough, summarized the view that "no particular change has been observed."
The study group made by experts analyzed the data by holding a regular meeting again by exchanging documents due to the influence of the new coronavirus.
In the hypocenter region of the Nankai Trough and its surroundings, it is called "deep low frequency earthquake" with the epicenter near the plate boundary in the western part of the Kii Peninsula from the 2nd to the 7th of last month and in the western part of Shikoku from the 17th to the 23rd of the last month. A small so-called earthquake was observed, and along with this, slight changes were seen in multiple "strain gauges" and tilt data in the surrounding area.
This is due to the "short-term slow slip" in which the boundary of the plate deep in the hypocenter region moves slowly over a relatively short period of time.
In addition, since last year, a slight crustal movement different from the previous trend has been observed in central Shikoku and the Shima Peninsula.
It is thought that this is due to the "long-term slow slip" in which the boundaries of the plates move slowly each year, and both are phenomena that have been repeatedly observed until now. No particular change has been observed, which is considered to have increased the possibility of the relative increase compared to normal times.”