Universities scientists Barcelona and Zaragoza in Spain found out that large-scale volcanic eruptions did not affect the massive disappearance of animals, including dinosaurs, at the end of the chalk period. The results of the study published in the journal Geology are another proof in favor of falling asteroid as the causes of extinction of ancient species.
Researchers analyzed deposits rich in microphosses (microscopic fossils), the age of which varies from 66.4 to 65.4 million years. Paleogenic period changed the chalk 66 million years ago. This border coincides with one of the five largest extinction on Earth. At the same time, global climate change occurred.
Scientists checked whether climatic shifts coincide with massive volcanism on the Dean plateau in India and the displacements of the Earth orbit. To do this, they conducted an isotopic carbon analysis-13 in the deposits of the cliffs of Sudyia, where there are many Foraminifera remains, extinct 66 million years ago. These deposits are also characterized by alternating rocks rich in clay or carbonate. Such rhythm is associated with cyclical changes in the orientation and inclination of the land axis.
It turned out that the extinction of the Foraminifera coincides with climatic disorders and accumulation of shock glass spheres due to the fall of the asteroid. Scientists also revealed three episodes of climate change, two of which are associated with the displacement of the Earth’s axis, and one with the trapping volcanism. None of these events caused a lateral mass extinction of species.