The tension between two tectonic plates near the Aleutian Islands in southwestern Alaska could cause a quake big enough to send a giant tsunami directly at California, experts say.
An area from San Francisco to Los Angeles lies in a perpendicular direction from a section of the trench where the Pacific Plate is digging under the edge of the North American Plate.
That section, called the Semidi, has lain unstressed for too long, according to geophysicist John Miller and a team at the U.S. Geological Survey, and so they postulate that the area is due for a rupture.
The resultant subduction quake caused by a rupture could trigger a tsunami, National Public Radio reports.
Miller stated that the area around the Aleutian Islands has produced other tsunamis. Because the trench is shaped in an arc, the tsunamis caused by various earthquakes have targeted different areas, largely missing population centers.
But the Semidi section, which last ruptured in 1788, is due for another rupture, as it typically ruptures every 180 to 270 years. Miller argued that a tsunami triggered by a rupture in the Semidi section could match the size of Japan’s giant tsunami in 2011.
Another USGS team found a section of the trench whose rupture would send a tsunami directly at Hawaii.
Led by geologist Rom Witter, that team has theorized that despite the fact that opposing edges along the Fox Island section of the trench have moved, unlike the stationary Semidi section, the section has caused quakes and tsunamis before.