Qualla: 1916–1917 Nantou Earthquakes

1916–1917 Nantou Earthquakes: Introduction

Sat, 13 Jun 2026 00:00:00 GMT

Photo credit Mikenorton, CC BY-SA 3.0. The seismometers went in first. Japan had taken control of Taiwan in 1895, and by 1898 — within just three years — colonial administrators had installed monitoring instruments in the Nantou region, the mountainous heart of central Taiwan. It was a practical impulse rooted in the knowledge that the island sat on one of the most seismically active arcs in the world. The instruments recorded and waited. For nearly two decades, the readings from Nantou remained quiet — unusually so, as it turned out. Then, in the late summer of 1916, the ground began to move.

Image: Mikenorton | CC BY-SA 3.0

1916–1917 Nantou Earthquakes: Eighteen Years of Quiet, Then August 1916

Sat, 13 Jun 2026 00:00:00 GMT

Photo credit Mikenorton, CC BY-SA 3.0. The first major earthquake in the sequence struck on August 28, 1916. It registered at magnitude 6.8 — the strongest quake in the entire series — but its hypocentre was relatively deep in the Earth's crust, which limited the surface damage that a shallower event of equal magnitud...

Image: Mikenorton | CC BY-SA 3.0

1916–1917 Nantou Earthquakes: January 5, 1917: The Deadliest Day

Sat, 13 Jun 2026 00:00:00 GMT

Photo credit Mikenorton, CC BY-SA 3.0. The quake that killed the most people came five months later, on January 5, 1917. It registered at magnitude 6.2 on the Richter scale — lower than the August event — but the critical difference was depth. This quake had a shallow hypocentre, meaning the energy released by the rup...

Image: Mikenorton | CC BY-SA 3.0

1916–1917 Nantou Earthquakes: A Sequence of Smaller Shocks

Sat, 13 Jun 2026 00:00:00 GMT

Photo credit Mikenorton, CC BY-SA 3.0. Beyond the two major events, the sequence included dozens of smaller earthquakes that, while not individually devastating, kept the population in a state of prolonged anxiety and prevented full recovery between the larger shocks. This is characteristic of earthquake sequences: th...

Image: Mikenorton | CC BY-SA 3.0

1916–1917 Nantou Earthquakes: Felt Across the Sea

Sat, 13 Jun 2026 00:00:00 GMT

Photo credit Mikenorton, CC BY-SA 3.0. The January 5, 1917 earthquake was not contained to Taiwan. Reports described the quake being felt across much of China, with particularly notable effects in Hangzhou, hundreds of kilometers away on the Chinese mainland. This reach across the Taiwan Strait speaks to the scale of ...

Image: Mikenorton | CC BY-SA 3.0

1916–1917 Nantou Earthquakes: What the Instruments Recorded

Sat, 13 Jun 2026 00:00:00 GMT

Photo credit Mikenorton, CC BY-SA 3.0. The seismological record of these earthquakes is part of their historical significance. By 1916, Taiwan had been under Japanese colonial administration for two decades, and the colonial government had invested in scientific monitoring infrastructure as part of its broader adminis...

Image: Mikenorton | CC BY-SA 3.0