Two of the strongest earthquakes recorded so far this year have struck The Coral Sea region of the Pacific Ocean.
A 7.5 magnitude earthquake was recorded southwest of Efate island, which is part of the Shefa Province in The Republic of Vanuatu, at 5:55 PM GMT. It was measured at a depth of 30km.
The second earthquake, which had a magnitude of 7.0 and prompted a tsunami warning, struck at 7:19 PM GMT about 69 kilometers (42 miles) south-southwest of the capital of Port-Vila on the island of Efate. It struck about 28.5 kilometers (17.7 miles) deep, making it a shallow earthquake, according to the United States Geological Survey (USGS). 5.9, 5.6 and 5.0 magnitude aftershocks were also recorded.
The USGS estimated that between 41,000 and 46,000 people may have felt strong shaking on nearby islands as a result of both earthquakes. It said there is a low likelihood of serious damage and casualties.
The anuatu Tsunami Warning Center issued a tsunami advisory for its central and southern islands after the second earthquake, urging all residents to move to higher ground until the all clear is given. A tsunami advisory is the highest level of alert in Vanuatu.
The agency said tsunami waves of 1.05 meter (3.4 feet) had arrived on the island of Efate less than an hour after the earthquake. It said there was no damage from the initial waves and has since cancelled the advisory.
Vanuatu, which is of volcanic origin, is some 1,750 kilometres (1,090 mi) east of northern Australia, 500 kilometres (310 mi) northeast of New Caledonia, west of Fiji, and southeast of the Solomon Islands, near New Guinea.
The island nation is on the so-called ‘Pacific Ring of Fire’, an arc of fault lines circling the Pacific Basin that is prone to frequent and large earthquakes. Volcanic eruptions also occur frequently in the region.
Most recently, on March 11, an enormous 9.0-magnitude earthquake struck off the coast of northeastern Japan, which is also on the Pacific Ring of Fire. The earthquake and a resulting tsunami left more than 15,600 people killed and more than 5,000 others missing.
And before that, on October 25, a powerful 7.7-magnitude earthquake struck just off the Mentawai Islands off the western coast of Sumatra in Indonesia. As a result, a wall of water killed at least 435 people on the islands and impacted more than 20 villages.
On December 26, 2004, one of the most powerful earthquakes ever recorded struck off the west coast of Sumatra. The 9.1-magnitude earthquake unleashed a deadly tsunami, striking scores of countries. In all, at least 227,898 people were killed.