252 million years ago, the world has changed for good due to a mass extinction caused by mostly the warming of Earth's climate, which hit the livings in oceans big in particular. That was the end of the Permian Period, which was home to cold-blooded, reptiles, therapsids, birds, and many others.
As the story goes, a period ends, another one starts. It was already known that the Siberian volcanic eruptions at times were mostly responsible for initiating the onset of Great Dying, aka the Permian-Triassic mass extinction that ended the Permian Period. This time, the researchers came up with another specific examination to add to the case.
The study has been published in the journal Nature Geoscience.
Scientists working on the project BASE-LiNE Earth led by Prof. Dr. Anton Eisenhauer from GEOMAR Helmholtz Centre for Ocean Research Kiel in cooperation with the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, have examined a previously considered ancient remain from the environmental archive: fossil brachiopods' shells.
They have, for the first time, had the chance to reconstruct overall of events had taken place million years ago, thanks to cutting-edge analytical techniques and innovative geochemical modeling.
"These shells were deposited at the bottom of the shallow shelf seas of the Tethys Ocean 252 million years ago and recorded the environmental conditions shortly before and at the beginning of extinction," explained Dr. Hana Jurikova, lead author of the study.
By examining the ancient brachiopod shells, they were able to detect the pH values of the oceans back then. As a result, it proved the oceans were acidified due to the high amount of absorbed carbon dioxide and took the pH levels off the balance.
The team reportedly used high-precision isotope analyses at GEOMAR along with high-resolution microanalyses on the state-of-the-art large-geometry secondary ion mass spectrometer at GFZ.
End of the Permian Period, therefore, was determined to be affected by the large pulse of carbon dioxide to the atmosphere spewed out of a massive volcanic eruption in Siberia.
Researchers analyzed that more than 100,000 billion tonnes of carbon reached the atmosphere which ended up poisoning many living organisms both on land and underwater.
"With this technique, we can not only reconstruct the evolution of the atmospheric CO2 concentrations, but also clearly trace it back to volcanic activity," explained Dr. Marcus Gutjahr, co-author of the study.