Mexico earthquakes demonstrate how height and distance dictate damage

Waves that ripple across the ground are especially destructive to tall buildings whereas intense shaking is more likely to destroy low-rise buildings

Two big earthquakes in Mexico last month were a tragic reminder that the country sits atop one of the most seismically active places on Earth. In particular, the magnitude 7.1 Puebla tremor on 19 September demonstrated Mexico's vulnerability, causing severe damage in Mexico City and taking more than 270 lives.

However, Mexico's most lethal earthquake remains the 1985 Michoacin earthquake of magnitude 8, which occurred 32 years earlier, to the day, and killed as many as 10,000 people. Strangely, many of the buildings that survived in 1985 succumbed to the tremors from the magnitude 7.1 last month. That's because the two earthquakes produced different kinds of shaking.