A strong earthquake has struck the chain of islands located between Alaska and Russia.

According to preliminary measurements by the U.S. Geological Survey, a 6.6-magnitude earthquake struck at 1:56 p.m. today (August 15) near the Andreanof Islands of Alaska in the Aleutian Islands chain.

The epicentre was located at a depth of 31 kilometres (19 miles) between Alaska and Russia, about 50 kilometres (31 miles) south of Tanaga Volcano and 108 kilometres (67 miles) west of Adak, Alaska.

The U.S. Tsunami Warning System is not issuing a tsunami advisory or warning.

This major quake follows a 6.4-magnitude earthquake, the largest seismic event ever recorded in the North Slope region of Alaska, that struck on August 12, and was followed by numerous aftershocks.