Map showing subduction zones and oceanic fracture zones. The blue bands are subduction interfaces – the parts of the subduction zone where the subducting plates are physically ‘grinding’ against the overriding plates. Coloured in red are the areas where oceanic fracture zones intersect these interfaces, which have higher probability of generating great earthquakes.

Map showing subduction zones and oceanic fracture zones. The blue bands are subduction interfaces – the parts of the subduction zone where the subducting plates are physically ‘grinding’ against the overriding plates. Coloured in red are the areas where oceanic fracture zones intersect these interfaces, which have higher probability of generating great earthquakes.

Map showing subduction zones and oceanic fracture zones. The blue bands are subduction interfaces – the parts of the subduction zone where the subducting plates are physically ‘grinding’ against the overriding plates. Coloured in red are the areas where oceanic fracture zones intersect these interfaces, which have higher probability of generating great earthquakes.