Cascadia Subduction Zone: A Potential Source of Devastating Earthquakes

Overview

The Cascadia Subduction Zone (CSZ) is a 1000 km (620 mi) long fault that stretches from Northern Vancouver Island to Cape Mendocino in northern California. It is a megathrust fault, where two tectonic plates move against each other. The CSZ has the potential to produce earthquakes of magnitude 9 or higher, which could cause widespread damage and loss of life.

Recent Developments

In 2023, the Pacific Northwest Seismic Network published a report highlighting the increasing likelihood of a major earthquake along the CSZ. The report found that there is a 10% chance of an earthquake of magnitude 9 or higher occurring in the next 50 years. This is a significant increase from the previous estimate of 5%.

Potential Impacts

A major earthquake along the CSZ could cause widespread damage and loss of life. The earthquake could trigger tsunamis, landslides, and fires. It could also damage critical infrastructure, such as bridges, roads, and water systems. The economic cost of a major CSZ earthquake is estimated to be in the hundreds of billions of dollars.

Preparedness

There are a number of steps that can be taken to prepare for a major earthquake along the CSZ. These steps include:

• Making sure you have a plan in place for what to do in the event of an earthquake.
• Having an emergency kit that includes food, water, first aid supplies, and other essential items.
• Strengthening your home and workplace to make them more earthquake-resistant.