New analysis by a global group of scientists provides weight to the concept that the mass extinction occasion resulting in the demise of non-avian dinosaurs was not solely attributable to an asteroid affect however was influenced by pre-existing environmental challenges — The examine focuses on sulfur ranges within the ambiance, presenting proof that earlier than the asteroid affect 66 million years in the past, the Earth was experiencing important volcanic exercise.
The researchers, led by College of Oslo geoscientist Sara Callegaro, analyzed rocks from the Deccan Traps, a large volcanic area in present-day West India. Utilizing a brand new measurement approach for sulfur concentrations, they discovered that volcanic sulfur degassing from this area might have led to repeated, short-lived world drops in temperature.
The Deccan Traps launched an immense quantity of molten rock, roughly a million cubic kilometers, with the sulfur-containing lava coinciding with the cooling Cretaceous local weather.
The sustained sulfur emissions from this volcanic exercise might have considerably altered the worldwide local weather, inflicting temperature fluctuations of as much as 10°C inside 100,000 years earlier than the asteroid affect.
The findings problem the standard narrative that attributes the extinction occasion primarily to the Chicxulub asteroid affect. As a substitute, the analysis means that the Earth’s weather conditions had been already unstable as a result of volcanic exercise, making a collection of volcanic winters that might have lasted a long time.
This environmental instability probably made survival difficult for each vegetation and animals, setting the stage for the eventual extinction of dinosaurs.
The examine contributes to the continuing debate between the asteroid and volcano theories relating to the reason for the mass extinction. Some researchers suggest that the asteroid affect triggered elevated volcanic exercise, whereas others counsel that volcanic exercise might have performed a task in serving to life get well from the asteroid strike.
The analysis underscores the importance of the Deccan Traps volcanism in shaping world weather conditions and its function within the lead-up to the mass extinction occasion.
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