Earth is tearing apart beneath the Pacific Northwest
3 hours ago
- Scientists have observed a subduction zone off Vancouver Island actively tearing apart, providing the first detailed view of a tectonic system dying piece by piece rather than all at once.
- Using seismic imaging and earthquake records from the CASIE21 experiment, researchers identified a 75-kilometer tear and large faults cutting through the Juan de Fuca and Explorer plates beneath the Cascadia region.
- The breakup process involves transform boundaries acting like geological scissors, forming microplates and creating slab windows that can alter volcanic activity.
- This discovery helps explain ancient tectonic remnants like the Farallon plate fragments off Baja California and provides insight into how subduction zones terminate episodically over millions of years.
- While the findings do not change short-term earthquake hazards for the Pacific Northwest, they may improve models for future rupture behavior by accounting for these newly identified structural breaks.