Geology

Harvard geoscientists have found the oldest direct evidence of plate tectonics on Earth, dating back 3.5 billion years. Analysis of ancient rocks from western Australia reveals early crustal drift and rotation. The discovery, published in Science, challenges notions of a rigid early planetary surface.

20. marts 2026 Rapporteret af AI

Researchers have identified volcanic eruptions, likely in Iceland, as the source of a mysterious platinum spike in Greenland ice cores from 12,800 years ago. This finding rules out a comet or asteroid impact and occurred decades after the onset of the Younger Dryas cooling period. The study provides new insights into abrupt climate shifts.

Simulations indicate that two massive hot rock blobs near Earth's core have played a role in generating and shaping its magnetic field, making it irregular over millions of years. Researchers analyzed ancient volcanic rocks and ran models to reach this conclusion. The findings suggest these blobs created uneven heat flow that affected the field's symmetry.

11. februar 2026 Rapporteret af AI

A new analysis of sediment cores from a Nepali lake reveals that major earthquakes in the central Himalayas occur randomly rather than at regular intervals, challenging fears of an imminent massive quake. Researchers identified at least 50 events of magnitude 6.5 or larger over the past 6,000 years, including eight since 1505. This finding suggests the region has experienced more seismic activity than previously thought.

Scientists have used swarms of minuscule earthquakes to map a hidden and intricate tectonic structure beneath northern California. This region, at the intersection of the San Andreas fault and the Cascadia subduction zone, involves five moving pieces rather than the expected three. The findings help explain past seismic events and improve hazard predictions.

10. januar 2026 Rapporteret af AI

Scientists have analyzed 3.7-billion-year-old rocks from Western Australia to uncover details about the early Earth and the Moon's origins. The study indicates that Earth's continents began forming around 3.5 billion years ago, long after the planet itself emerged. Comparisons with Apollo mission samples support the theory of a massive cosmic collision birthing the Moon.