Geology of Colombia - Seismic Activity

Seismic Activity

Tectonic movement of the cordilleras continues today, as evidenced by frequent seismic activity. Indeed, Colombia remains part of the Pacific Ring of Fire, an active seismic area that surrounds the Pacific basin. The country is located where three lithospheric plates—Nazca, Caribbean, and South American—converge, and their movement produces different types of geologic faults. Almost all of the country's many earthquakes in recent centuries have occurred in the mountainous and coastal regions. Recent major earthquakes include those in Popayán on March 31, 1983, and in the nation's coffee-growing belt on January 25, 1999; and one on March 6, 1987, on the border with Ecuador, measuring 7.0 on the Richter scale. Recent earthquakes that struck Colombia's Pacific coast areas have included one accompanied by a tsunami in Tumaco, Nariño Department, on December 12, 1979, measuring 7.9 on the Richter scale, the largest in northwestern South America since 1942; another on November 15, 2004, with a magnitude of 6.7; and one on September 10, 2007, measuring 6.8. Although construction standards are high for new buildings in the main cities, smaller cities and rural zones are particularly vulnerable to earthquakes.