In a recently published study, Princeton scientists claimed that they have sufficient evidence to conclude that asteroid alone did not kill all dinosaurs, which go against a widely accepted view known as the K-Pg extinction theory.
About 66 million years ago, an ancient asteroid landed just off Mexico's Yucatán Peninsula, creating the famous Chicxulub crater, 150 km (93 miles) wide and 20 km (12 miles) deep. Many paleontologists believe that the immensely powerful impact disrupted the global climate and kill 75% all species on Earth, including most dinosaurs.
However, using techniques in geochronology (the science of determining the age of rocks), the Princeton researchers discovered four major volcano eruptions at the Deccan Traps, a vast plateau in west-central India, around K-Pg extinction timeline. What's more important, the first one predated the Chicxulub impact for tens of thousands of years. The ash and gas release caused by the series of eruptions could've blocked sunlight of a vast region and influenced climate in the Eastern Hemisphere. Therefore, they proposed that the extinction was likely a result of both asteroid impact and the massive volcano eruptions in their discovery.
Source: Anton Petrov via Youtube