Nazca Plate drives seismic activity in South America

The Nazca Plate, an oceanic tectonic structure located in the eastern Pacific Ocean, is the primary driver of intense seismic activity along the western coast of South America. According to the Geophysical Institute of Peru (IGP), the plate collides with and subducts beneath the South American continent, a process that has shaped the Andes Mountains over millions of years.

The plate moves at a rate of approximately seven to eight centimeters per year near the Peruvian coast. Seismic hazards arise when specific sections of the fault become locked while movement continues, accumulating tension that is eventually released as high-magnitude earthquakes. This geological dynamic is a central component of the Pacific Ring of Fire.

A 2025 study published in the Journal of Geophysical Research: Solid Earth reconstructed the plate's trajectory over the last 34 million years. The research noted a nearly 20% reduction in convergence rates over the past 780,000 years, though experts emphasize that this deceleration does not eliminate the ongoing threat of significant earthquakes in Peru, Chile, Ecuador, and Colombia.