A new study suggests that it was not a massive asteroid that caused the dinosaurs to go extinct, but rather one of the world’s largest volcanic eruptions.
The new study published in Science Magazine online suggests that the dinosaurs’ demise is the result of volcanoes, not the Chicxulub asteroid impact as previously thought. The study focuses on an area in India called the Deccan Traps. The Deccan Traps is a large area of mountain-sized basalt lava deposits that were created, by what scientists consider, by one of the largest volcanic eruptions that Earth has even seen. The original lava flows, according to Life Science, may have covered as much as 580,000 square miles.
Some scientists have previously investigated the idea that these volcanic eruptions were the source of dinosaur extinction. However, scientists were unable to determine exactly when the eruptions took place. Conversely, researchers did know that the Chicxulub space rock crashed into eastern Mexico’s Yucatan Peninsula around the same time that many dinosaur species began to go extinct. In fact, after the impact, dinosaurs and 75 percent of other Cretaceous species suddenly vanished. Thus, researchers believed that Chicxulub was responsible for the extinction.
The new research focused on the fact that many animals and plants had already started disappearing from the fossil record before the asteroid impact took place. Could something else have started the mass extinction and the asteroid simply tipped it over-the-edge? That is exactly the conclusion that MIT researchers found with the most recent Deccan Traps study. NBC reports that lead study author, Blair Schoene, a geologist at Princeton University in New Jersey, was able to pinpoint exactly when the Deccan Traps were formed to date the volcanic eruptions by using U-Pb zircon geochronology. The youngest lava flows were determined to have emerged 66.29 million years ago, about 250,000 years before the Chicxulub asteroid crash. The new timeline suggests that the beginning of the extinction, when many species began to disappear, began at the same time as the volcanic activity.
The new study helps piece together the exact mechanisms that led to the dinosaurs’ extinction. It appears from the latest research that the end of the dinosaurs was a two-fold process. It began with the large volcanic eruptions that created the Deccan Traps and was sped up when the Chicxulub impact took place. NBC notes that volcanic extinction proponents blame climate-altering gas on the mass extinction.
“Proponents of the volcanic extinction model argue that climate-altering volcanic gases made Earth inhospitable for many species by changing temperatures and ocean acid levels.”
Ultimately, the researchers were unable to determine exactly which flows correlate directly to the extinction and note that more research must be done to pinpoint exactly how much of a role volcanic activity played in the extinction, compared to the asteroid impact.
Similarly, another study suggests that a comet caused the dinosaur extinction, not an asteroid.
What do you think of the latest research? Does the Deccan Traps research help fill in some holes in the previous extinction hypothesis?