Experts say California and Japan quakes unrelated to deadly Venezuela tremors

A magnitude 6.9 earthquake struck off northeastern Japan on Thursday, but Japanese authorities said there was no tsunami warning and no immediate injuries were reported. Seismologists said that quake, a magnitude 5.6 temblor near Redwood Valley in Mendocino County on Wednesday, and the deadly twin earthquakes that hit Venezuela were unrelated events on separate fault systems. The California quake activated the U.S. Geological Survey’s ShakeAlert early warning system and was expected to cause only relatively localized damage.

In Northern California, the U.S. Geological Survey placed the shaking near Redwood Valley and said the impact should stay relatively local. The warning system kicked in as the 5.6 quake moved through Mendocino County, a reminder that even moderate earthquakes can jolt a wide area without producing the kind of widespread destruction seen in stronger events.

Japan’s quake struck off the country’s northeastern coast, and the Japan Meteorological Agency said there was no danger of a tsunami. No irregularities were found at nuclear facilities, and no injuries were immediately reported after the offshore 6.9-magnitude event, which briefly focused attention on a part of Japan that has lived through some of the world’s most damaging seismic disasters.

The most severe damage was in Venezuela, where two strong earthquakes hit north-central areas 39 seconds apart. One U.S. Geological Survey event page listed a magnitude 7.5 quake 16 kilometers southwest of Morón, Venezuela, at 22:05:11 UTC, and relief updates put the pair at preliminary magnitudes of 7.1 and 7.5. The shocks triggered tsunami advisories for parts of the Caribbean before those warnings were cancelled. Buildings collapsed, rescuers searched through rubble in Caracas, and emergency crews moved into affected neighborhoods as the scale of the disaster became clear.

Reports from Venezuela said dozens of people were killed and hundreds were injured. Some described the event as the country’s biggest earthquake in more than a century, a comparison often set against the Oct. 29, 1900 offshore quake, described in one account as magnitude 7.7. The timing of the California, Japan and Venezuela quakes was striking, but experts said it was coincidence, not evidence of a single global trigger moving through the planet.