Almost 66 million years ago, Earth was hit by a massive asteroid that triggered a global extinction event. A new study argues that life may not have been so good even before the asteroid crashed into the surface of our planet as a high concentration of mercury could be found within the atmosphere.
The fresh batch of data will add even more fuel to the controversies related to the fate of dinosaurs. Some researchers argue that the asteroid was the sole reason for the extinction of dinosaurs, but others think that the answer to the question may not be so simple.
It is thought that violent volcanic eruptions took place for tens of thousands of years before the impact, and the release of a large amount of lava may have contributed to the demise of the 75% of all the life that could be found on the planet.
The Earth’s Atmosphere Was Affected by Pollution Before the Chicxulub Asteroid Impact
By examining relevant fossils from all over the world, a team of researchers has discovered a steady increase in mercury and carbon dioxide during a series of long eruptions that contributed to the formation of a region known as Deccan Traps. The eruptions lasted for over one million years and led to the formation of western India during the timeframe between the Cretaceous and the Paleogene.
Mercury is classified as a toxic chemical element, and large amounts tend to be released during volcanic eruptions. When the mercury reaches the ocean, it becomes a powerful reactive that is consumed by phytoplankton. Mollusks will consume the phytoplankton.
An analysis of the shells found in the Deccan Traps area infers that the eruptions paved the way towards long-lasting climatic and ecological events. While mercury has been found in sediments, this is the first study that focuses on the presence of the chemical in shells. It also suggests that an abrupt warming event started 250,000 years before the impact. The study was published in a scientific journal.