What Lies Beneath: Geophysicists Decode Mysterious Deep Seismic Signals

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

A new study reveals that PKP precursor seismic signals, which have mystified scientists for years, originate from ultra-low velocity zones deep beneath North America and the western Pacific. These findings by University of Utah researchers connect these zones to significant geological features like hotspot volcanoes, using advanced seismic techniques to trace their origins back to the core-mantle boundary.

PKP Precursors and Seismic Mysteries
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.