Portland, Ore. (KOIN) — This week marks more than 300 years since the last Cascadia Subduction Zone earthquake and tsunami struck the Pacific Northwest.

The Oregon Office of Emergency Management announced in a tweet saying Wednesday, Jan. 26 marks 322 years since the event. The agency announced the anniversary to encourage Oregonians to prepare and practice earthquake safety during Cascadia Earthquake Preparedness Week.

The Big One is known as the Cascadia Subduction Earthquake that would impact a 600-mile fault located 70-100 miles off the West Coast of North America.

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“Geologists have determined that major earthquakes of magnitudes 8 or 9 have occurred many times in the past in the Pacific Northwest, including most recently January 26, 1700, and that another could occur at any moment,” said a proclamation by Gov. Kate Brown’s office. “Given our current lack of preparedness, such a quake could create the worst natural disaster in North American history.”

OEM encourages people to be prepared to be on their own with enough food, water and supplies for a minimum of two weeks after a major earthquake and tsunami event.

To learn how to prepare for earthquakes, click here.