A new study using over a decade of offshore data reveals that the Cascadia Subduction Zone is not a single, smoothly rupturing fault. Instead, it behaves like a chain with different sections, each behaving differently. The study found that the northern section (Vancouver Island and surrounding areas) is strongly locked, building up stress, while the central section (Oregon coast) experienced a slow-slip event, suggesting a temporary loosening of the rock.
The Cascadia fault is more complex than previously thought, with varying segments exhibiting different behaviours. Northern Cascadia is locked and building strain, while central Cascadia shows evidence of slow slip and fluid transport. The Washington to northern Oregon segment, with its smooth and shallow geometry, could potentially rupture more continuously and produce strong inland shaking, posing a significant risk to densely populated areas.
