Research by EPS PhD student Yiming Zhang published in PNAS (https://www.pnas.org/doi/abs/10.1073/pnas.2202875119) was just featured in AGU's news publication EOS: https://eos.org/articles/swinging-strength-of-earths-magnetic-field-coul.... As the news piece explains: "Yiming Zhang and his coauthors collected and studied rocks from the (failed) North American Midcontinent Rift—a region where 1.1 billion years ago there was voluminous volcanism. The rocks that Zhang targeted are unique aggregations of crystals known as anorthosite xenoliths that formed deep in Earth’s crust but were brought close to the surface with magma that fed lava eruptions into the rift. The team found surprisingly high paleointensity values that signal a turbulent core—more spirited than might be expected for a liquid core lacking a solid center and stronger than Earth’s magnetic field today."
July 11, 2022
PNAS