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6.9-magnitude strikes Alaska’s Aleutian Islands

This region is on the Pacific Ocean’s ‘ring of fire’ – where great land plates meet and one dives beneath another – and so is subject to frequent earthquakes.

View interactive map></a< | July 26, 215 earthquake in the Aleutian Islands. View interactive map>reports that a magnitude 6.9 earthquake – a very strong earthquake – struck in Alaska’s Aleutian Islands late Sunday night (morning of July 26, 2015, UTC). There were no immediate reports of injuries. No tsunami warning was issued.

Details of the quake from USGS follow:

Time
2015-07-27 04:49:46 (UTC)

Nearby Cities
73km (45mi) SW of Nikolski, Alaska
1538km (956mi) WSW of Anchorage, Alaska
1556km (967mi) SE of Anadyr’, Russia
1569km (975mi) WSW of Knik-Fairview, Alaska
2280km (1417mi) W of Whitehorse, Canada

Earthquakes are common in Alaska’s Aleutian arc. USGS explains:

The Aleutian arc extends approximately 3,000 km [2,000 miles] from the Gulf of Alaska in the east to the Kamchatka Peninsula in the west. It marks the region where the Pacific plate subducts [dives below] into the mantle beneath the North America plate.

This subduction is responsible for the generation of the Aleutian Islands and the deep offshore Aleutian Trench.

The curvature of the arc results in a westward transition of relative plate motion … accompanied by westward variations in seismic activity, volcanism, and overriding plate composition.

Bottom line: Strong earthquake in Aleutian arc region of Alaska on July 26-27, 2015. This region is located on the Pacific Ocean’s so-called ring of fire – where great land plates meet and one dives beneath another – and so is subject to frequent earthquakes.

Deborah Byrd

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