Although at lower risk for major earthquakes, Thursday’s tremor is a reminder that Cuenca and the southern sierra are still vulnerable
Thursday morning’s 5.6 magnitude earthquake, 50 miles northwest of Cuenca, should be a wake-up call that all of Ecuador is in a seismically active region, according to Ecuador’s Geophysical Institute.
Henry Bermeo, director of the Institute’s Seismic Network for southern Ecuador, said that residents need to be prepared for earthquakes. “Although most concern is focused on the coast and in the northern sierra, we cannot lose sight of the fact that earthquakes can happen almost everywhere in Ecuador, including Cuenca,” he said.
Bermeo said that his office has observed higher levels of seismic activity in the area near Thursday’s epicenter in Cañar Province in recent months. “Actually, this earthquake is good news since it relieves pressure that had been building in the earth’s crust and reduces the chances for a larger earthquake,” he said.
The earthquake, which occurred at a depth of 87 kilometers, caused no damage except to rattled nerves, Bermeo said.
According to Hugo Yepes, national director for earthquake monitoring, the area around Cuenca is at lower risk for a catastrophic quake than most other populated areas of the country. “In recorded history, Cuenca has not suffered a destructive earthquake, and that covers the 450 years since the Spanish arrived.”
Yepes explains that the Andes region of southern Ecuador is geologically older and more settled than most of the mountain range. “This explains why it is less seismically active”, he said. “It is very important to understand, however,” he cautioned, “that the entire country, including this area, is vulnerable and we must remain vigilant.”
Ecuador lies on the eastern rim of the area known as the Pacific Ring of Fire, Yepes said. There have been at least 37 earthquakes estimated to be of magnitude 7 or greater on the Richter Scale since 1541, when written records by the Spanish were first kept, the institute says. The government believes that more than 80,000 died in those quakes.
It is important, institute officials say, that residents know the level of risk of the areas where they live. For example, Manta is at high risk for a catastrophic earthquake.
Countrywide, the area of greatest risk, says the institute, is the coast, particularly the area from Manta north to the Colombian border. Other areas at high risk include the northern Andes, including the cities of Ibarra, Ambato, Riobamba and Quito.
One of the nine most powerful quakes in history struck the northern coast of Ecuador in 1906, killing 2,000 near Esmeraldas and sending a tsunami across the Pacific Ocean that killed hundreds more in Hawaii and Japan. The quake measured 8.9 or 9 on the Richter scale, equaling the 2012 quake in Chile. Another killer quake, measuring 7.3, hit a hundred miles to the south in 1998, devastating the town of Bahia de Caraquez. Thirteen years later, many buildings in Bahia still show the scars of that quake and a number of them still stand abandoned.
In the Andes, Riobamba and Ambato have been destroyed by large earthquakes in the 18th, 19th and 20th centuries while Quito has suffered serious damage on three occasions. Ambato still shows damage from a 1949 quake that registered 7.1 magnitude.