Residents of São Paulo and its metropolitan region felt tremors on July 25, 2024, following a powerful earthquake in northern Chile [1].
This event is significant because seismic waves from the Andes region occasionally travel far enough to be perceived in urban centers of Brazil, causing public alarm despite the distance.
The earthquake struck at 6:52 p.m. Brasília time [2]. It registered a magnitude of 6.9 [1], with the hypocenter located at a depth of 101.3 km [3]. The seismic energy was strong enough to be detected thousands of kilometers away in the state of São Paulo [1].
Local residents reported various sensations during the event. One resident said, "Everything shaking" [4]. Another resident described the sensation as a strong tremor, saying it felt "as if a truck were passing in the street" [5].
While the tremors were noticeable to people in high-rise buildings or those in quiet environments, there were no immediate reports of structural damage within the city of São Paulo. The phenomenon occurs when seismic waves travel through the Earth's crust, a process that allows high-magnitude events in Chile to be felt in South American neighbors.
Authorities and seismic monitoring agencies tracked the event to ensure the stability of regional infrastructure. The magnitude 6.9 [1] event serves as a reminder of the geological activity prevalent along the Pacific coast of South America.
“"Everything shaking"”
The perception of tremors in São Paulo resulting from an earthquake in Chile demonstrates the efficiency of seismic wave propagation through the South American plate. While Brazil is generally considered seismically stable, these 'reflex' tremors can trigger widespread panic in densely populated cities, highlighting the need for public education on the difference between local tectonic activity and distant seismic echoes.
