Earthquake Prediction Analysis Report
【Delivery Date: Feb. 20, 2017 】
Prediction analysis of earthquakes M4 or more to occur by Feb. 28, 2017

【Data analysis 】
Earthquake prediction research center(Representative director:Onoe Masataka , Analysis Center Director Shigeyoshi Yagishita)
MK building, 1-4-12 kaigan, Minato-ku Tokyo , ZIP105-0022 TEL 03-6627-0528 FAX: 03-3436-3132

Predicted epicenters of earthquakes with a seismic intensity 4 or more by Feb.28

20170220_03 [Latest crustal movement]
-Large crustal movement in Shari, Hokkaido.
-As mentioned in last week’s report, M5 class occurred in “Eastern offshore of Hokkaido” and “Offshore Choshi”.
-Mentioned in last week’s report was “Earthquakes with deep focuses occurring from the Philippine Sea Plate to Offshore Kyoto”. →M4.7 quake with deep hypocenter occurred in the far seas off Kyoto.
-Number of earthquakes increasing around the boundary of Okinawa Plate.

[Predicted epicenters of earthquakes with a seismic intensity 4 or more by Feb.28]
■M5: Eastern Hokkaido (max seismic intensity 3)
■M4: Offshore Fukushima (max seismic intensity 3)
■M4: Northern Ibaraki, Offshore Choshi, Southern Ibaraki – Western Chiba (seismic intensity 3)
*Details in the following pages.

This week’s crustal movement: Hokkaido

20170220_07 ■M5: Eastern offshore of Hokkaido (max SI-), Eastern Hokkaido (max SI 3), Offshore Urakawa (max SI 3)

The large crustal movements seen in Northern Hokkaido (Horonobe, Nakagawa, etc.) were not observed this week, and the possibility of a major earthquake in Northern Hokkaido has decreased. This week, large crustal movement marking “3.4cm/week” was observed in “Shari2”. This is probably effected by the physically insensible seismic intensity earthquakes ranging from micro to M2.9 occurring nearly 100 times since Feb.13 (Mon), around Shari. If such micro earthquakes continue, because M5 class earthquake has occurred in the past in offshore Shari, there is a possibility of a similar scale earthquake this week. M3-4 class earthquakes occurring more frequently around Offshore Urakawa to eastern offshore of Aomori. There is a possibility of a stronger M5 class earthquake.

This week’s crustal movement: Tohoku

20170220_08 ■M4: Offshore Fukushima (SI 3), Offshore Miyagi (SI 3), Offshore Akita (SI -)

The small scale crustal movements observed in multiple points of Inland Fukushima are decreasing. Therefore, the possibility of an over M6 major earthquake in Offshore Fukushima has also decreased this week. However, because of the “frequent small scale earthquakes” in “Offshore Fukushima – Northern Ibaraki”, M5 or less earthquake is predicted again this week. But from the present earthquake occurrence situation, the possibility of a “seismic intensity 5 or more earthquake” is low.
Large crustal movements observed around “Gunma, Niigata”. Depending on the observation values, there is a possibility of a fault-type earthquake. We will keep close watch over daily crustal movement values and earthquake occurrences.

This week’s crustal movement: KANTO/HOKURIKU/TOKAI

20170220_09 ■M4: Northern Ibaraki (SI 3), Offshore Choshi (SI3), Southern Ibaraki – Western Chiba (SI 3)

“M5.4, max seismic intensity 4 quake occurred on Feb.19 in Offshore Choshi of Chiba”. As mentioned in page 10 of last week’s report (Feb.13), frequent micro earthquakes were observed prior to this quake. Because in the Kanto Region, M3 class earthquakes have occurred in “Northern Ibaraki”, “Offshore Choshi”, and “Southern Ibaraki – Western Chiba”, from past earthquake occurrence situations, “max seismic intensity 3” level earthquake is predicted. Also, M5 class is predicted in “Offshore Ibaraki” but a high seismic intensity is unlikely to be observed since occurrence will be in the far seas.

This week’s crustal movement: KANSAI/CHUGOKU/SHIKOKU

20170220_10 ■No large crustal movement seen prior to a major earthquake observed.

Although small scale, crustal movements facing towards the “Nankai Trough direction” were observed in “Seidan” of Awajishima and “Hirokawa” of Wakayama. Also, small scale earthquakes are occurring in “Offshore Shikoku – Offshore Wakayama” area, where normally earthquakes are rare. Therefore, we will keep close watch over daily crustal movements and direction, occurrences of micro earthquakes, and will deliver an emergency report if a large anomaly is observed.
Also, middle scale crustal movements were observed in “Kyotonishikyo”. We will concentrate on this area because small scale earthquakes are occurring in the surrounding areas and the possibility of this leading to a major earthquake cannot be denied.

This week’s crustal movement: KYUSHU

20170220_11 ■No large crustal movement seen prior to a major earthquake observed.

This week, large crustal movements were not observed in the Kyushu Region. Also, there were no occurrences of earthquakes over M4 last week. Therefore, the possibility of a major earthquake occurrence this week in the Kyushu Region is low.
In the last two weeks, M3-4 class earthquakes have continued to occur around the boundary of the “Yangtze & Okinawa Plates”, making this an area that requires attention. In this area, “Nov.14, 2015, M7.1” has occurred in the past. However, because it occurred in the far seas, it only registered “max seismic intensity 4” but because there is the possibility of tsunami, we will keep close watch.

This week’s crustal movement: OKINAWA

20170220_12 ■M5: Northern offshore of Ishigaki-jima (max SI 2), Southern offshore of Ishigaki-jima – Taiwan (SI 1)

In the latest week, large crustal movements were not observed from the Satsunan Islands through Okinawa Islands, and the possibility of a major earthquake registering an over seismic intensity 5 tremor to occur is low. However, M4 earthquakes are frequently occurring around the “boundary of Yangtze & Okinawa Plates” and the “boundary of Okinawa & Philippine Sea Plates”. This trend is likely to continue this week and a M5 class earthquake is predicted. However, even if it occurs, the earthquake epicenter will be in the far seas and will not be a major earthquake observing a high seismic intensity.

Earthquake prediction research center(EPRC)