Geoscientists at the University of Toronto have made a major discovery that reshapes our understanding of plate tectonics, particularly regarding oceanic plates. Their study, published in Geophysical Research Letters, reveals that the Pacific Plate—which spans most of the Pacific Ocean floor—is undergoing active deformation due to deep-sea faults. This groundbreaking research introduces a more dynamic and fragile view of oceanic plates, overturning the long-standing belief that they remain largely intact as they drift across Earth’s mantle.
Traditionally, oceanic plates were thought to be rigid and resilient, gliding smoothly over the mantle until they reached subduction zones. However, the new research reveals that the Pacific Plate tearing occurs well before it reaches those boundaries. The study focuses on four massive plateaus in the Western Pacific—Ontong Java, Shatsky, Hess, and Manihiki—which were previously believed to be structurally robust due to their thickness. In fact, these very features appear to be the weakest parts of the plate, making them especially prone to internal fracturing.
Using supercomputer simulations and seismic data, the team found that these plateaus host large faults caused by immense geological forces as the plate is pulled westward. This tension, intensified near subduction zones like those stretching from Japan to New Zealand, leads to internal rupturing—what scientists are now identifying as Pacific Plate tearing. Postdoctoral researcher Erkan Gün emphasized how surprising it was to find this kind of deformation deep within an oceanic plate, a phenomenon previously only observed in continental interiors.
One key insight from the study is that the forces affecting the plate are not distributed evenly. Instead, the composition and structure of specific regions, such as the sub-oceanic plateaus, make them more susceptible to damage. As a result, the Pacific Plate tearing could have far-reaching implications, especially for seismic and volcanic activity. The researchers suggest that past volcanism in these regions might be linked to these structural failures, although more data is needed to confirm ongoing activity.
Professor Russell Pysklywec, who co-authored the study, explained that this discovery adds new depth to the theory of plate tectonics. It suggests that oceanic plates are not uniform or invulnerable, but instead are evolving, weakening, and fracturing in ways we are only beginning to understand. The model presented in this study proposes a significant revision to how scientists view oceanic plate dynamics.
Ultimately, this research opens up new pathways for exploring the links between deep-sea faults, plate motion, and geological activity. It demonstrates that Pacific Plate tearing is a critical factor in the tectonic processes shaping Earth’s surface. By rethinking the stability of oceanic plates, scientists can better assess the risks and origins of seismic and volcanic events in the Pacific region and beyond.
www.dailygalaxy.com/2025/05/pacific-plate-is-tearing-apart-new-faults-2/