- A spate of 11 earthquakes took place on the sea bed, 6 miles below the surface
- The quakes ranged in magnitude from 2.8 to 5.6 on the Richter scale
- They occurred on the Juan de Fuca tectonic plate
- This forms part of the runs along the Cascadia subduction zone, which scientists say has the potential to trigger a monster 9.0 earthquake in the future
A series of earthquakes have shaken a region of ocean off the west coast of the US.
Scientists have detected a cluster of 11 earthquakes, ranging in magnitude from 2.8 to 5.6 on the Richter scale.
The cluster occurred on the seabed at the Juan de Fuca tectonic plate, around six miles (10km) underwater.
This plate forms part of the Cascadia subduction zone, which runs from Northern California to British Columbia.
Previous studies have warned this geological spot of weakness has the potential to deliver an earthquake much stronger than the infamous San Andreas fault.
Seismologists say a full rupture along the 650-mile-long (1,000 km) offshore fault could trigger a 9.0 magnitude earthquake and an accompanying tsunami.
The largest of the earthquakes occurred at 7:44 am (10:44 am ET/3:44 pm BST), and was large enough to qualify as a 'moderate' earthquake.
Earthquakes of this magnitude on the Richter scale are categorised as 'causing damage of varying severity to poorly constructed buildings.
'At most, slight damage to all other buildings will be felt by everyone.'
The Juan de Fuca tectonic plate is one of the smallest in the world, and is under constant strain from the Pacific plate.
For around 300 years, Juan de Fuca has been pushed down, slowly submerging beneath the much larger Pacific plate.
This geological activity has caused the Cascadia Subduction Zone (CSZ) 'megathrust' fault, which is a 650 mile (1,000 km) long line that stretches from Northern Vancouver Island to Cape Mendocino California.