Mantle - GoKawiil

Study ties Great Unconformity gap to mantle currents, not just glaciers

Researchers Nicolas Flament and Santosh Dhungana published a Nature study proposing that slow-moving currents in Earth's mantle raised continents over hundreds of millions of years, exposing rock to glacial erosion before the land sank and was buried under new sediment. This process, they argue, helps explain the Great Unconformity, a geologic gap in the rock record spanning 200 million to over a billion years, found across North America and parts of northern Europe and China. The finding challenges the long-standing explanation that global glaciation alone, during a possible 'Snowball Earth' period 720 to 635 million years ago, carved away the missing rock layers.

arstechnica.com · 2026-11-06

Study links decades-long shifts in Earth's day length to inner core gravity

Researchers Hao Zhang and Mathieu Dumberry report in Nature that gravitational coupling between Earth's solid inner core and its mantle explains multidecadal changes in day length of a few milliseconds. They combined seismological data on inner-core rotation with a model of outer-core flow derived from magnetic field measurements to reach this conclusion.

nature.com · 2026-09-23

Study links Earth's day-length changes to core-mantle torque forces

A study published in Nature reports that small variations in the length of Earth's day, on the order of milliseconds over decades, can be explained by competing gravitational, mechanical and electromagnetic forces between Earth's solid inner core, molten outer core and rocky mantle. Researchers, including geophysicist Mathieu Dumberry, had long suspected core-mantle interactions caused these fluctuations but lacked clarity on which specific forces were responsible.

nature.com · 2026-09-23

Study links Earth's inner core gravity to decade-scale day-length shifts

Researchers analyzed length-of-day (LOD) records from 1964 to 2019, after removing known effects from the atmosphere, oceans, tides and surface mass changes, to isolate multidecadal variations. They modeled these residual variations using torque equations that account for gravitational pull from the inner core alongside electromagnetic and topographic coupling at the core-mantle boundary, finding that gravitational torque from the inner core contributes to the slow, multidecadal changes in how long a day lasts.

nature.com · 2026-09-23