2014 Nagano earthquake

What Happened

At 22:08 local time on 22 November 2014, a shallow earthquake struck the northern Japan Alps in Nagano Prefecture, with its epicentre in the Kamishiro district southeast of the resort town of Hakuba. The United States Geological Survey measured the event at magnitude 6.2 Mw, while the Japan Meteorological Agency (JMA, 気象庁, Kishō-chō) recorded it at 6.7 MJMA, a different scale that tends to return higher numbers for shallow crustal quakes in Japan. Peak ground shaking reached IX — "Violent" — on the Modified Mercalli intensity scale, and Shindo 6 Lower (震度6弱, shindo roku-jaku) on the JMA seismic intensity scale, the third-highest of the JMA's ten levels.

The shaking toppled houses in the Kamishiro and Hakuba areas, damaged roads and buried sections of the region's ski infrastructure under landslides. No one died. Forty-one people sustained injuries, ranging from mild to severe.

Background

The earthquake takes its Japanese name from the Kamishiro fault (神城断層, Kamishiro dansō), a shallow fault running beneath the Kamishiro district. Japan sits on four tectonic plates — the Pacific, Philippine Sea, Eurasian and North American — and the resulting compression has fractured the archipelago into thousands of active faults. Most of the country's deadliest earthquakes are of this inland, shallow-fault type rather than the great offshore megathrust events that generate tsunamis.

Northern Nagano is a well-known fault zone. The Kamishiro fault had been mapped and studied before 2014, and the November quake ruptured it along a surface trace that geologists were able to inspect directly in the days afterwards. The event occurred in the 26th year of the Heisei era (平成26年), the reign period of Emperor Akihito that ran from 1989 to 2019.

Why It Mattered

The 2014 Nagano earthquake was a reminder of how much damage a moderate inland quake can do in a rural, mountainous region. The epicentre lay in a valley floor of soft sediment, which amplified the shaking well beyond what the magnitude alone would suggest — the same effect that made the 1995 Kobe earthquake so destructive. Wooden houses with heavy tiled roofs, common in the area, collapsed or were left leaning.

The quake also struck a region whose economy depends on winter tourism. Hakuba had hosted events during the 1998 Nagano Winter Olympics, and the November timing placed the earthquake only weeks before the ski season. Landslides cut roads and damaged slopes, and the visible surface rupture across fields and roads became a widely photographed illustration of active faulting for the Japanese public.

Because the death toll was zero, the event is often cited in Japanese disaster-preparedness material as a case where building standards, early warning and a moderate hour of occurrence combined to limit loss of life. The 41 injuries and the structural damage nonetheless fed into revisions of local evacuation planning and fault-rupture hazard maps for Nagano Prefecture.

The Name in Japanese

The full Japanese name is 長野県神城断層地震, read in kana as ながのけんかみしろだんそうじしん, and romanised as Nagano-ken Kamishiro dansō jishin. It translates literally as "Nagano Prefecture Kamishiro Fault Earthquake". Breaking it down character by character:

• 長 (なが, naga) — "long". The first element of the place name Nagano.
• 野 (の, no) — "field" or "plain". Together, 長野 (Nagano) means "long field", the name of both the prefecture and its capital city.
• 県 (けん, ken) — "prefecture". Japan's 47 prefectures are its top-level administrative divisions; Nagano is one of them, landlocked in the centre of Honshu.
• 神 (かみ, kami) — "god" or "divine spirit". In Shintō, kami are the spirits or deities venerated at shrines.
• 城 (しろ, shiro) — "castle". The compound 神城 (Kamishiro) is a place name in the Hakuba area; the characters are read together as Kamishiro rather than by their individual meanings.
• 断 (だん, dan) — "to cut off" or "sever". Here it begins the geological term for a fault.
• 層 (そう, sō) — "layer" or "stratum". Combined, 断層 (dansō) means "fault" in the geological sense — a fracture in rock along which the two sides have moved.
• 地 (じ, ji) — "ground" or "earth".
• 震 (しん, shin) — "to shake" or "tremble". Together, 地震 (jishin) is the standard Japanese word for "earthquake".

The name is therefore a precise geological label: it identifies the prefecture, the specific fault that ruptured, and the type of event. Japanese earthquake names frequently follow this pattern, naming the fault or the epicentral district rather than using a date, which is why the same event can appear in English as "the 2014 Nagano earthquake" and in Japanese as the "Kamishiro Fault earthquake".

Key Figures

• Date and time: 22 November 2014, 22:08 local time (UTC +9).
• Magnitude: 6.2 Mw (United States Geological Survey); 6.7 MJMA (Japan Meteorological Agency).
• Maximum intensity: IX (Violent) on the Modified Mercalli intensity scale; Shindo 6 Lower (震度6弱) on the JMA seismic intensity scale.
• Epicentre: 36.6916667° N, 137.8900000° E, southeast of Hakuba, Nagano Prefecture.
• Deaths: none.
• Injuries: 41, mild to severe.
• Era: Heisei 平成, year 26 (2014).