Millions under tsunami threat as fallout from monster 7.8 earthquake threatens US

A massive 7.8 magnitude earthquake^[1] has set off tsunami alerts in Alaska^[2], Hawaii^[3], and Russia.

The quake struck near the Petropavlovsk-Kamchatsky region, off Russia’s east coast^[4], on Thursday at 2:58pm ET.

The National Oceanic and Atmospheric Administration’s (NOAA) tsunami warning system indicates that Hawaii faces a threat from dangerous waves caused by the earthquake.  

Two tsunami watches have been issued for Alaska’s Aleutian Islands^[5], the closest US territories to the earthquake.

This advisory in Alaska covered an area from Attu to the Amchitka Pass, which is 125 miles west of Adak, Alaska.

People in these areas should avoid beaches, harbors, and low-lying coastal areas and stay alert for updates this evening as the waves arrive.

Meanwhile, a tsunami with waves one to three feet high is expected to reach Hawaii Thursday night.

According to AccuWeather, the earliest these waves would reach the state would be 8:51pm ET.

A 7.8 magnitude earthquake has struck near Russia’s east coast, triggering tsunami warnings in Alaska and Hawaii

The US Geological Survey (USGS) has detected more than a dozen aftershocks, ranging from 4.8 to 5.6 magnitude.

In Russia, locals near the epicenter are under a higher state of alert, as the tsunami warning system expects waves between three and 10 feet to strike.

This could create more significant coastal flooding or damage, especially in low-lying areas.

The warning in Hawaii is currently at an advisory-level alert, meaning minor waves or strong currents could occur, but widespread flooding is unlikely.

No warnings have been issued for the US West Coast. One of the closest points in San Francisco, California, is roughly 4,300 miles away from the quake’s epicenter, and seismic waves are not expected to reach that far. 

A tsunami is a series of large ocean waves caused by a sudden disturbance in or near the sea, like an earthquake or volcanic eruption.

These waves can travel across entire oceans and cause flooding and damage when they hit coastlines.

Unlike regular waves, tsunamis can be very long and powerful, sometimes reaching heights of 10 feet or more, like the ones striking the Russian coast.

Russia’s Foreign Office issued an urgent warning following a huge 8.8 magnitude earthquake that struck off the coast of Russia on July 29 (pictured)

The Kamchatka Peninsula has been repeatedly hit by major earthquakes this summer, including a magnitude 7.4 earthquake on September 13 and a devastating magnitude 8.8 earthquake^[6] that occurred on July 29.

Millions were placed under tsunami advisories after the July quake, including residents in Japan, Hawaii, and the US West Coast. 

The US Geological Survey (USGS)^[7] called Thursday’s 7.8 earthquake a giant aftershock of the larger quake that struck on July 29. It’s the largest recorded aftershock linked to that event near Russia’s coast.

USGS added that the major quake was triggered by a type of movement called reverse faulting, where two massive pieces of the Earth’s crust push against each other.

In this area, the Pacific Plate is sliding beneath the North American Plate at a speed of about three inches per year. 

This movement occurs along a massive underground boundary called the Kuril-Kamchatka subduction zone. 

More than a dozen additional earthquakes have already struck the region since the 7.8-magnitude quake erupted, all of them registering over 4.6 magnitude.

The July mega quake also led to a powerful volcanic eruption of the Klyuchevskoy volcano in Kamchatka.

Located around 280 miles north of the regional capital, Petropavlovsk-Kamchatsky, Klyuchevskoy is one of the highest volcanoes worldwide.

Scientists will likely be on alert again for another eruption following Thursday’s series of major earthquakes.