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takyon writes:

Scientists Detect Unexpected Widespread Structures Near Earth's Core (Science Daily)

University of Maryland geophysicists analyzed thousands of recordings of seismic waves, sound waves traveling through the Earth, to identify echoes from the boundary between Earth's molten core and the solid mantle layer above it. The echoes revealed more widespread, heterogenous structures—areas of unusually dense, hot rock—at the core-mantle boundary than previously known.

Scientists are unsure of the composition of these structures, and previous studies have provided only a limited view of them. Better understanding their shape and extent can help reveal the geologic processes happening deep inside Earth. This knowledge may provide clues to the workings of plate tectonics and the evolution of our planet.

[...] Using a machine learning algorithm called Sequencer, the researchers analyzed 7,000 seismograms from hundreds of earthquakes of 6.5 magnitude and greater occurring around the Pacific Ocean basin from 1990 to 2018. Sequencer was developed by the new study's co-authors from Johns Hopkins University and Tel Aviv University to find patterns in radiation from distant stars and galaxies. When applied to seismograms from earthquakes, the algorithm discovered a large number of shear wave echoes.

Also at phys.org.

Journal Reference:
D. Kim, V. Lekić, B. Ménard, et al. Sequencing seismograms: A panoptic view of scattering in the core-mantle boundary region [$], Science (DOI: 10.1126/science.aba8972)

Original Submission