A strike-slip fault is when two blocks slip past one another, like the San Andreas Fault line. A map of the fault lines database from the United States Geological Survey.

A brand new 45-mile fault line has been discovered stretching along Canada's Vancouver Island, just north of the Washington state border, and may pose a tsunami risk to people nearby.

KETCHIKAN, Alaska (AP) — Federal agencies have completed the first high-resolution mapping of a fast-moving underwater tectonic fault that extends from Vancouver Island, Canada, to southeast Alaska.

"This fault is about 125 km long from Washington to Victoria, which would be an earthquake, potentially, in the magnitude of 6.5, 7 perhaps even 7.5 if the entire fault zone ruptured at once ...