A deep - focus earthquake in seismology (also called a plutonic earthquake) is an earthquake with a hypocenter depth exceeding 300 km. They occur almost exclusively at oceanic - continental convergent boundaries in association with subducted oceanic lithosphere. They occur along a dipping tabular zone beneath the subduction zone known as the Wadati -- Benioff zone.
where do earthquakes that have deep foci usually occur
at oceanic - continental convergent boundaries in association with subducted oceanic lithosphere