The Permian extinction event was the biggest shake-up of life that Earth has ever seen: in the “Great Dying” that took place 250 million years ago, more than 90 percent of marine species were killed and about 70 percent of land animals vanished. The cause of this catastrophe has been debated for years, but new research suggests that volcanic eruptions triggered massive coal fires that pumped pollution into the air, eventually poisoning the planet.
The study, published in Nature Geoscience, is based on new findings from arctic rocks that date back to the Permian period, when all of the planet’s land masses formed a supercontinent called Pangaea. When the researchers analyzed the rocks, they found signs of a coal-based apocalypse.
Besides the usual miniscule clumps of organic matter, they also found tiny bubble-filled particles called cenospheres. These frothy little blobs form only when molten coal spews into the atmosphere, the researchers say…. [The cenospheres] must have been created when massive amounts of molten rock—more than 1 trillion metric tons—erupted through overlying coal deposits in Siberia to form lava deposits known as the Siberian Traps. [ScienceNOW]
Today it’s tempting to think of Antarctica as an icy wasteland, hospitable for penguins and seals but not much else. However, before the continent was covered by a permanent ice sheet, it may have been a refuge from a world in chaos, according to findings published in a journal called Naturwissenschaften.
Jörg Fröbisch of Chicago’s Field Museum says that a distant relative of mammals, a cat-sized herbivore called Kombuisia antarctica survived the Permian-Triassic Extinction 250 million years ago by migrating from southern Africa to Antarctica. At the time of the end-Permian extinction, Antarctica was some distance north of its present location, warmer than it is today, and not covered with permanent glaciers [The Telegraph].
The explosion of a volcano located in present-day China might have caused a mass extinction 260 million years ago, adding more evidence that volcanoes might have been to blame for some of the world’s most catastrophic die-offs. Because the eruptions occurred in a shallow sea the researchers were able to study both the volcanic rock and the overlying layer of sedimentary rock containing fossilized marine life [AP], giving researchers a better picture of how the explosion altered the balance of life.
The injection of hot lava in a sea would have produced a massive cloud formation that could spread around the world, cooling the planet and producing acid rain [AP], according to the study, which was published in Science and led by paleontologist Paul Wignall. Based on analysis of the volcanic and sedimentary rock at the eruption site, the scientists hypothesized that ash and lava spewed from a sea covering the volcano, showering plants and animals with atmospheric carbon. “When fast flowing, low viscosity magma meets shallow sea it’s like throwing water into a chip pan there’s spectacular explosion producing gigantic clouds of steam” [Telegraph], says Wignall.