What happened
Early on the morning of 17 January 1995, local time, a fault running beneath the Akashi Strait and the city of Kobe slipped at shallow depth under a densely built-up area. Thousands of older wooden houses with heavy roofs collapsed, and a stretch of the elevated Hanshin Expressway toppled onto its side. Fires consumed entire blocks. More than 6,000 people died. The disaster led to stricter Japanese building codes and a dense nationwide network of seismometers.
How to read these data
Magnitude measures the energy released at the focus: each step is about 32 times more energy, so an M 9 earthquake releases about a thousand times more energy than an M 7. Its effects, however, also depend on focal depth, distance to cities, ground conditions and building quality – a shallow M 7 beneath a city can be deadlier than a deep M 8 under the ocean.
Data: USGS ComCat (usp0006rew) · Wikipedia (pl) · Wikipedia (en)