2016 Kumamoto earthquakes

What Happened

The 2016 Kumamoto earthquakes were a sequence of two major shocks that struck Kumamoto Prefecture on the island of Kyushu in April 2016. A foreshock with a magnitude of 6.2 hit at 21:26 JST (12:26 UTC) on April 14, 2016, at a depth of roughly 11 kilometres beneath the region. Two days later, the mainshock followed at 01:25 JST on April 16, 2016 (16:25 UTC on April 15), registering a magnitude of 7.0 at a depth of about 10 kilometres, directly beneath Kumamoto City.

The two earthquakes together killed 277 people and injured 2,809 others. Of the deaths, 50 were caused directly by the shaking, while 218 were classified as disaster-related deaths, a category that covers fatalities from aggravated injuries or worsened illnesses during evacuation. An additional 5 deaths, caused by heavy rains from June 19–25, were also linked to the earthquake sequence. This made the disaster the deadliest earthquake in Japan since the 2011 Tōhoku earthquake and tsunami, a record it held until the 2024 Noto earthquake.

Severe damage spread across Kumamoto and neighbouring Ōita Prefectures, where numerous buildings collapsed and fires broke out. More than 44,000 people were forced to evacuate their homes in the aftermath.

Background

The earthquakes occurred during the Heisei period (1989–2019), in the 28th year of the Heisei era. The region around Kumamoto sits on the active Futagawa and Hinagu fault zones, which run through the central part of Kyushu. The foreshock and mainshock were shallow crustal earthquakes, meaning they originated close to the surface, which amplified the intensity of ground shaking in populated areas.

Kumamoto City, the prefectural capital, lies in a basin surrounded by mountains, and the local building stock included many older wooden structures that were vulnerable to strong lateral shaking. The sequence also triggered landslides and ground liquefaction in the surrounding countryside, compounding the structural damage. The timing of the mainshock, just after 1 a.m., caught many residents asleep in their homes.

Why It Mattered

The Kumamoto earthquakes exposed the danger of shallow, inland fault ruptures, which produce violent shaking over a concentrated area even at moderate magnitudes. The high number of disaster-related deaths—218 of the 277 total—highlighted how evacuation conditions, stress, and interrupted medical care can kill more people than the tremors themselves. That pattern pushed Japanese disaster planners to pay closer attention to the health of evacuees in shelters, not just to building collapse.

The event also marked a grim milestone: it was the deadliest earthquake in Japan in the five years since the 2011 Tōhoku disaster, and it remained so until the 2024 Noto earthquake surpassed it. For the language learner, the disaster also produced a wave of news coverage and official documents in Japanese, making its terminology—such as the word for disaster-related deaths—a practical part of contemporary vocabulary.

The Name in Japanese

The Japanese name for this event is 熊本地震. In kana, it is read くまもとじしん, and in romaji it is Kumamoto jishin. The name literally means "Kumamoto earthquake."

Breaking it down character by character:

• 熊 (くま, kuma) — meaning "bear." This character is used here as part of the place name Kumamoto, where it does not carry its animal meaning independently but contributes the sound kuma.
• 本 (もと, moto) — meaning "origin" or "base." In this compound it provides the moto sound of Kumamoto and, together with 熊, forms the place name. The full place name 熊本 is often glossed as "bear's origin," though it is simply the name of the prefecture and city.
• 地 (じ, ji) — meaning "ground" or "earth." This is the first character of the common word for earthquake.
• 震 (しん, shin) — meaning "to shake" or "tremble." Combined with 地, it forms 地震 (じしん, jishin), the standard Japanese word for earthquake.

Note that the full official name in Japanese is 平成28年熊本地震 (Heisei 28-nen Kumamoto jishin), which adds the era year: "Heisei year 28 Kumamoto earthquake." In everyday usage, however, 熊本地震 alone is sufficient.

Key Figures

• Foreshock magnitude: 6.2, struck April 14, 2016, at 21:26 JST, at a depth of about 11 kilometres.
• Mainshock magnitude: 7.0, struck April 16, 2016, at 01:25 JST, at a depth of about 10 kilometres beneath Kumamoto City.
• Total deaths: 277, comprising 50 direct deaths, 218 disaster-related deaths, and 5 deaths from heavy rains linked to the earthquake.
• Total injured: 2,809.
• People evacuated: more than 44,000.
• Location: Kumamoto Prefecture, Kyushu Region, Japan, centred at coordinates 32.8490000, 130.6350000.
• Era: Heisei period, year 28 of the era (2016).