Researchers at the University of Texas at Austin found evidence in the rock samples from the Chicxulub submarine crater that dinosaurs became extinct as a result of the global cooling that followed the collision of a giant asteroid with Earth. Their work was reported by the journal of the National Academy of Sciences of the USA Proceedings of the National Academy of Sciences.
American scientists have received new evidence of the fidelity of the theory, according to which, about 65 million years ago, as a result of the fall of an asteroid in the territory of modern Mexico, a global environmental disaster occurred. The impact of the celestial body formed a huge crater and provoked the occurrence of forest fires and tsunamis in vast territories.
As a result of the collision, a huge amount of sulfur compounds fell into the atmosphere, and it began to transmit sunlight and heat worse. The ensuing global cooling led to the extinction of a large number of animal species, including a whole superorder of dinosaurs.
Scientists have drilled the seabed at the alleged site of the fall of the asteroid. Particles of coal and sedimentary rocks found in the samples showed that the consequences of the explosion that occurred as a result of the fall of a celestial body were large-scale forest fires and giant tsunami waves that swept almost a thousand kilometers inland. Then the waves swam away and brought with them so much sedimentary rock that in just a day the depth of the crater decreased by 130 meters.
Scientists also found a large amount of sulfur in the rock samples around the Chiksulub crater, but there was practically no sulfur inside the well. The researchers concluded that due to the huge temperature during the impact of the asteroid, sulfur evaporated and was released into the atmosphere in the form of sulfur compounds. As a result, less light and heat began to reach the earth's surface, and global cooling began.
The head of the research group and one of the leaders of the international scientific expedition for drilling the crater Chiksulub Sean Gulik describes the death of dinosaurs as follows: “First they were fried, and then frozen. On this day, not all died, but many dinosaurs. "
According to scientists, after the explosion in the vicinity of the Chiksulub crater, about 325 billion metric tons of various substances got into the atmosphere - tens of thousands of times more than during the eruption of the Krakatau volcano in 1883, after which the average temperature on the Earth dropped by about 2 ° C by five years old.
“The study of the epicenter of the explosion helped us make a more detailed description of the events. We can study the processes that occurred at the time of the collision, as if from the point of view of an eyewitness, ”says Sean Gulik.