Possible Tsunami Threat to Guam After 7.7 Magnitude Earthquake in Pacific

A tsunami alert has been triggered for Guam after a powerful magnitude 7.7 earthquake struck near New Caledonia in the western Pacific.

The National Tsunami Warning Center said the quake hit southeast of the Loyalty Islands, east of Australia at around 11:20 p.m. CHST (8:20 a.m. ET) on Wednesday at a depth of around 20 miles.

The center warned there is currently a tsunami threat for Guam as well as the islands of Rota, Tinian and Saipan. The earliest impacts would be around 6:13 CHST a.m. on Thursday.

The alert later added that there is no tsunami danger for the U.S. West Coast, British
Columbia, or Alaska, and some of the islands may experience non-damaging sea-level changes.

The magnitude of the earthquake was also downgraded from its original 7.9 to 7.7.

In a tweet, seismologist Stephen Hicks wrote: "There has just been a earthquake near New Caledonia in the western Pacific where the Australian Plate is colliding with and subducting beneath the Pacific Plate. It was preceded by a couple of M6 foreshocks <30 mins before. A tsunami warning is currently active.

"Magnitude estimates are currently quite varied and range from M7.1 (EMSC) to M7.9 (USGS)," Hicks added. "These estimates will likely converge over the coming minutes as more data is received and these solutions are manually revised."

According to a 2002 study by geologists James Lander and Lowell Whiteside of the University of Colorado and Paul Hattori from the US Geological Survey Guam Geophysical Observatory, Guam has only had only three tsunamis that were large enough to cause damage in the last two centuries—in 1849, 1892 and in 1993.

In 2017, the Offices of Guam Homeland Security and Civil Defense still warned residents that global warming could still affect the island in years to come.

"With everything changing in global warming, a lot of these natural disasters are changing," Camerine Francisco, tsunami grants specialist, told The Guam Daily Post.

"Where there wasn't snow, there's snow. Where there weren't earthquakes or tsunamis, all of a sudden there's huge disasters."

Guam does experience infrequent earthquakes due to its location within the so-called Ring of Fire.

The Ring of Fire, also called the Circum-Pacific belt, is a zone of earthquakes and active volcanoes surrounding the Pacific Ocean which runs up from New Zealand to the Philippines, Indonesia and Japan down the the west coasts of North and South America.

In total, 90 percent of the world's earthquakes take place within the Ring of Fire, and it is home to 75 percent of the planet's volcanoes

guam
(File photo) Tourists enjoy the activities along Tumon beach on the island of Guam on August 11, 2017. A Tsunami alert has been triggered for Guam after a powerful magnitude Earthquake struck near New Caledonia VIRGILIO VALENCIA/AFP