San José, Costa Rica, since 1956

Magnitude-6.6 earthquake rocks Costa Rica on Tuesday night

Another large earthquake hit Costa Rica’s Nicoya Peninsula and rocked the entire country on Tuesday night. No injuries and only minor damages were reported.

The temblor, which lasted at least 30 seconds, registered a magnitude-6.6 at a depth of 37 kilometers at 6:45 p.m., according to the Volcanological and Seismological Observatory of Costa Rica (Ovsicori). The U.S. Geological Survey also cited a magnitude-6.6.

The National Emergency Commission immediately dismissed the threat of a tsunami.

Hundreds of temblors and aftershocks have rattled the peninsula, located on the northwest coast in the province of Guanacaste. The biggest occurred on Sept. 5, when a magnitude-7.6 earthquake in the Nicoya Peninsula was felt throughout Costa Rica and in both Nicaragua and Panama. That quake caused minor injuries and did tens of thousands of dollars in damage.

Ovsicori confirmed that the magnitude-7.6 temblor was the “big one” – the powerful earthquake long expected in Nicoya. However, the fault did not rupture all of its energy, releasing only 40 percent of the pent-up energy at the fault line.

Marino Protti, Ovsicori’s lead scientist, stated the rest of the energy could be released in several ways, including through another major earthquake.

Many aftershocks have followed the early September quake, including Tuesday night’s earthquake and a magnitude-5.3 temblor on Oct. 10 with an epicenter 27 miles south of Liberia, the capital of Guanacaste.

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