34 km SW of Puerto Madero, Mexico

A magnitude 7.3 earthquake — a major event — struck near 34 km SW of Puerto Madero, Mexico on April 29, 1970, at a shallow depth of about 35 km. An earthquake this size would have been felt strongly across the surrounding region; shallow earthquakes release their energy close to the surface, so they tend to cause the strongest shaking and the most damage. Casualties, damage and the recovery depend on local building standards, population and distance from the epicentre — the news coverage, references and photos below capture what happened on the ground.