Geophysicists find link between seismic waves called PKP precursors and strange anomalies in Earth’s mantle

For the decades since their discovery, seismic signals known as PKP precursors have challenged scientists. Regions of Earth’s lower mantle scatter incoming seismic waves, which return to the surface as PKP waves at differing speeds. For the decades since their discovery, seismic signals known as PKP precursors have challenged scientists. Regions of Earth’s lower mantle scatter incoming seismic waves, which return to the surface as PKP waves at differing speeds. Earth Sciences Phys.org – latest science and technology news stories