Coda-correlation wavefields reveal direction-dependent inner-core shear-wave speed, ~5 s faster in directions oblique to the Earth’s rotation axis than directions parallel to the equatorial plane.
Earth’s interior
Diamond Discovery Unearths Secrets of the Deep
A diamond inclusion has revealed a new mineral, davemaoite, as well as hints about the workings of our planet’s interior.
A Simple Recipe for Making the First Continental Crust
Laboratory experiments serendipitously revealed a rock-forming process that might explain how the first continental crust formed on Earth—and possibly on Mars.
Processes in Earth’s Mantle and Surface Connections
A new AGU book presents a multidisciplinary perspective on the dynamic processes occurring in Earth’s mantle.
A Novel Thermobarometer to Infer Mantle Melting Conditions
The algorithm RevPET automatically reverses the complex multi-phase fractional crystallization path of oceanic basalts and offers new perspectives for advancing mantle thermobarometry.
First Report of Seismicity That Initiated in the Lower Mantle
A 4D back-projection method revealed that aftershocks of the 2015 earthquake beneath the Ogasawara (Bonin) Islands occurred as deep as about 750 kilometers.
Lava from Bali Volcanoes Offers Window into Earth’s Mantle
Lava from the Agung and Batur volcanoes provides a near-pristine picture of Earth’s mantle and raises questions about all volcanoes along the Indonesian Sunda Arc and beyond.
Previous Intra-oceanic Subduction Found Beneath South America?
Newly mapped fast velocity slabs in the lower mantle may be remnants of westward dipping intra-oceanic subduction, before flipping to the present eastward subduction beneath South America at 85 Ma.
Seafloor Seismometers Look for Clues to North Atlantic Volcanism
Did the mantle plume that fuels Iceland’s volcanoes today cause eruptions in Ireland and Great Britain long ago? A new project investigates, while also inspiring students and recording whale songs.
Peter M. Shearer Receives 2020 Inge Lehmann Medal
Peter M. Shearer was awarded the 2020 Inge Lehmann Medal at the virtual AGU Fall Meeting in December. The medal is for “contributions to the understanding of the structure, composition, and dynamics of the Earth’s mantle and core.”