An international team of scientists was able to build the most comprehensive dating mass Permian extinction
According to Lenta.ru, new results are consistent with the hypothesis that the cause of the disaster on a planetary scale was powerful volcanic activity. The article appeared in the scientific journal Science, and its summary results ScienceNOW.
Mass Permian extinction is the largest (of great extinctions were five) extinction of living things in history. It was about a quarter of a billion years ago, at the boundary of the Permian and Triassic periods. It is believed that at this time gone for about 90 percent of the living creatures on the planet. Version of the involvement of volcanoes in extinction is the most common, however, until recently, scientists did not have enough evidence. In particular, it was not known how fast the process.
In a new study, the researchers conducted a statistical analysis of the fossil record from around China. Used for dating the isotopic ratio of lead and uranium. The main merit of the scientists said that they have perfected a method of preparation of samples for the study, as well as the modified mass spectrometer, as a result they have achieved a record of accuracy — 100 thousand years.
As a result, scientists have been able to establish that the extinction was 252.28 million years ago. Species died out at the same time in the sea and on land, and the entire process took about 200,000 years (and could, according to scientists, meet and 100 thousand). All these results are consistent with the time of appearance of the Siberian Traps. These geological formations — a consequence of a special type of magmatism, which is poured out on the surface of a large amount of magma.
In January 2011 in Nature Geoscience published an article in which scientists argued relationship Siberian Traps and extinction. In particular, they found in the sediments of the microscopic particles of coal — in their opinion, it is this "additive" to emissions allowed them so effectively destroy almost all life on Earth, especially in the ocean, killing 96 percent of living organisms.