An earthquake measuring 4.7 magnitude on the Richter scale hit the US state of Alaska on Sunday.The US Geological Survey reported that the epicenter of the quake occurred 70 km southwest of the island of Onalaska, at a depth of 57.3 km.There have been no reports of material or human damage caused by the tremor so far.Alaska is located above the Pacific Ring of Fire, an area where tectonic plates meet, and the friction of which leads to strong seismic and volcanic activity.Source: Qatar News Agency