Why did the 1985 Mexico City earthquake cause so much damage?

The catastrophic damage caused by the 1985 Mexico City earthquake was primarily due to the city's unique and precarious topography.1

The central part of the capital was constructed on the dry bed of the drained Lake Texcoco, which consists of loose lacustrine sediments. These soft soils amplified the earthquake's shock waves, causing ground motion that measured five times greater than in the city's outlying districts. In some areas, these subsoils shifted or "liquefied" beneath building foundations.12

Furthermore, the city's architecture played a critical role in the destruction. Buildings between 5 and 15 stories tall were most severely affected because their physical structure interacted with the seismic waves to create a harmonic resonance, which significantly exacerbated the swaying of these structures. This phenomenon led to the collapse of more than 400 buildings and caused extensive damage to thousands more, including several major hospitals, which hampered emergency medical efforts.1