Earthquakes tagged posts

When a crystal structure of bismuth (right) is decompressed from 32,000 atmospheres (3.2 GPa) to 12,000 atmospheres (1.2 GPa) it melts into a liquid at about 23,000 atmospheres (2.3 GPa) (middle). It then recrystallizes at 12,000 atmospheres (left). The so-called metastable liquid produced by this decompression occurs in a pressure-temperature range similar to where the supercooled bismuth is produced. Supercooled liquids are cooled below the freezing point without turning into a solid or a crystal. Credit: Chuanlong Lin and Guoyin Shen, Carnegie Institution

Phase transitions surround us – for instance, liquid water changes to ice when frozen and to steam when boiled...

These pseudotachylites — fine grained rocks — are from the British Isles. Credit: Image courtesy of Yale University

A new study shows that rocks formed by the grinding together of other rocks during earthquakes are rich in trapped hydrogen – a finding that suggests similar seismic activity on Mars may produce enough hydrogen to support life. Researchers from Yale, the University of Aberdeen, and Brock University studied rock formations around active fault lines in the Outer Hebrides, off the coast of Scotland. “Previous work has suggested that hydrogen is produced during earthquakes when rocks fracture and grind together. Our measurements suggest that enough hydrogen is produced to support the growth of microorganisms around active faults,” said Yale geologist Sean McMahon.

While humans an...