The range of earthquake sizes represented by the whole model.
Median Tectonic Line (MTL) fault zone (FROM Sanuki-sanmyaku-nanen eastern segment TO Ishizuchi-sanmyaku-hokuen segment)
中央構造線断層帯(讃岐山脈南縁東部区間~石鎚山脈北縁区間が同時に活動)
What this earthquake source model represents and how to read its data.
Reference model · not a forecastThe long-term chance that an earthquake represented by this model occurs within that period.
The long-term chance that an earthquake represented by this model occurs within that period.
This model in plain language
J-SHIS classifies this as a major active-fault model. It represents the underground area that may rupture along the fault, not one predicted earthquake. The model covers an overall magnitude of Mw 7.6. Its source elements span depths of 2–16 km below the surface. It considers 2 rupture patterns; this is not the number of expected earthquakes.
Japan terrain and the source model in 3D
Use the terrain map and city labels to locate the approximate source area, then switch below ground to inspect its generalised extent and depth. It does not reproduce the original source elements or show future epicentres or rupture progression.
Ctrl-drag to tilt · city names remain visible on the map
How to read the model data
Magnitude describes the overall size of the modelled earthquake, not the Shindo felt in a particular place. The same magnitude can produce different shaking depending on distance, depth and ground conditions. A range shows both model limits.
Probabilities are long-term values in the Y2020 model. They do not predict an earthquake on a particular day, in a particular year or at one exact location. Some models do not provide a value.
Places where J-SHIS considers this model
In J-SHIS calculations, this model is among the leading earthquake sources for these places. It does not mean the earthquake will start inside their boundaries or that every place would shake in the same way.
- Hayashima Town→
- Aioi City→
- Kamigori Town→
- Aki City→
- Okawa Village→
- Wake Town→
- Toyo Town→
- Geisei Village→
- Motoyama Town→
- Hidaka Village→
- Inami Town→
- Ibara City→
Show 48 more places
- Osakikamijima Town→
- Kamikatsu Town→
- Tosa City→
- Susaki City→
- Yasuda Town→
- Otoyo Town→
- Tosa Town→
- Sakawa Town→
- Ochi Town→
- Bizen City→
- Naka Town→
- Mugi Town→
- Minami Town→
- Niihama City→
- Ozu City→
- Kochi City→
- Kami City→
- Ino Town→
- Niyodogawa Town→
- Satosho Town→
- Takehara City→
- Tonosho Town→
- Nankoku City→
- Konan City→
- Ako City→
- Gobo City→
- Kawabe, Hidakagawa Town→
- Okayama Kita Ward→
- Okayama Naka Ward→
- Okayama Higashi Ward→
- Okayama Minami Ward→
- Tamano City→
- Kasaoka City→
- Akaiwa City→
- Yakage Town→
- Fukuyama City→
- Kaiyo Town→
- Naoshima Town→
- Imabari City→
- Kamijima Town→
- Tobe Town→
- Kasai City→
- Hidaka Town→
- Setouchi City→
- Asakuchi City→
- Mihara City→
- Onomichi City→
- Higashihiroshima City→
Technical model data
J-SHIS identifiers and calculation parameters. You do not need them for an everyday reading of this page.
- Model version
- Y2020 The edition of J-SHIS data used on this page.
- Probability case
- MAX MAX is the J-SHIS calculation case used on this page. It does not mean a certain ‘worst case’ event.
- J-SHIS code
- F0201EG The identifier used for this model inside J-SHIS.
- Estimation method code
- SIM An abbreviation for the statistical process used to calculate probability. It is not a danger grade.
- Source elements
- 6 Source elements are the pieces J-SHIS uses to build the source shape. A larger count means a more detailed or complex model; it is not a hazard score, a fault count or the number of expected earthquakes.
- Depth
- 2–16 km The modelled depth range below the ground surface.
- Element length
- 30–86 km The length of individual source elements, not necessarily the total length of a fault zone.
- Element width
- 12–18 km The width of the inclined source elements below ground.
- Dip angle
- 40–90 ° The element’s tilt from horizontal: 0° is horizontal and 90° is vertical.
- Strike
- 253.9–257.3 ° The compass direction in which an element extends, measured clockwise from north.
- Rupture patterns
- 2 Alternative rupture arrangements or sequences considered by the model.
- Display grid cells
- 51 Regular aggregated grid cells used to depict the source area. This is not the number of source records or original shapes.
Source and limitations
Source: J-SHIS, operated by Japan’s National Research Institute for Earth Science and Disaster Resilience (NIED). JISHINDESU organises the Y2020 maximum-case data for presentation. This page is not an earthquake prediction, building-safety assessment or evacuation notice. Use current JMA and local-authority information for safety decisions.
In accordance with the J-SHIS terms, we publish only model-level summaries and coarse display geometry that cannot reproduce the original vertex sequences. This is not a redistributed copy of the source dataset.
Data retrieved: 05/09/2026