An earthquake measuring 5.1 magnitude on the Richter scale struck off the coast of Vanuatu on Sunday.The earthquake occurred 192 km from Sola village on the island, at a depth of 55.3 km, according to the United States Geological Survey (USGS).There were no reports of casualties or material losses due to the earthquake.Vanuatu, an island country in the South Pacific Ocean, is an archipelago of volcanic origin that lies on the Pacific Ring of Fire, a zone of frequent seismic activity.Source: Qatar News Agency