New Study Links Volcanic Eruptions with Mass Extinction
March 26, 2013
Massive volcanic eruptions some 200 million years ago likely caused the extermination of half of all species (kinds of living things) on Earth. A new study recently published in the journal Science appears to confirm that a series of massive volcanic eruptions occurred very close to the time of the End-Triassic Extinction. The End-Triassic Extinction was a widespread die-off of land and sea species, which allowed for the rise of the dinosaurs.
The gigantic eruptions occurred across an area that now stretches from Nova Scotia to Morocco, when the land on Earth was one giant continent called Pangaea. The volcanoes released huge amounts of carbon dioxide and other greenhouse gases that caused global warming and other atmospheric changes. Many species of plants and animals would not have survived this dramatic shift in the chemical makeup of the atmosphere and in temperature.
The authors of the new study have dated the volcanic eruptions to 201.5 million years ago, close to the time of the End-Triassic Extinction. Carnegie Tech geologist Terrance Blackburn and his colleagues were able to accurately gauge the time by studying ancient lava flows in modern-day New Jersey, Nova Scotia, and Morocco. They found spores and pollen as well as plant and animal fossils from the Triassic Era in sediment layers underneath the lava flows, but not in layers above them. This suggests that the widespread eruptions and the massive die-off were interconnected.
Geologist Paul Renne, of the Berkeley Geochronology Center, noted that the findings are “a nice confirmation of what we and others have been aware of for some time. The main difference is the dating that they used is more precise than our results were.”
Additional World Book articles:
- The Great Dying (a special report)
- What Has Caused Mass Extinctions? (a special report)