Pyroclastic flow caused mass death of dinosaurs: expert  

南京大學科學家發(fā)現(xiàn)恐龍死亡之謎:火山爆發(fā)所致

南京大學副教授姜寶玉等科學家團隊在東北地區(qū)熱河生物群動物化石遺址中，發(fā)現(xiàn)保存完好的恐龍、哺乳動物和鳥類化石：這些古生物的遺骸，都有被燒焦過的痕跡——這跟龐貝城所見的人類遺骸很相似，發(fā)現(xiàn)地也因此被稱為中國古生物的“龐貝城”。 [查看全文]

(ECNS) -- A new study has found that pyroclastic flow 100 million years ago was the main reason behind the mass mortality of dinosaurs and other animals in northeastern China, the Modern Express observed on Tuesday.

The discovery was published in "Nature Communications" by a research team under the leadership of Jiang Baoyu, an associate professor at Nanjing University.

In the 1990s a series of well-preserved fossils were discovered in the Jehol Biota (an ecosystem in northeast China between 133 and 120 million years ago), and those discoveries have changed people's understanding of the lives of early birds and mammals, as well as the dinosaurs they shared an ecosystem with.

To figure out why so many well-preserved fossils were found in that region, Jiang and four other scientists launched a research project in 2011.

After three years of study, researchers discovered that this remarkable preservation has been the result of a Pompeii-like event, where hot ash from a volcanic eruption entombed the animals.

Using six different fossils discovered in the region, Jiang found marks of fast-moving ash and hot gas that can only result from a nearby volcanic eruption. The bones showed black streaks, which suggest that charring had occurred.

"We are shocked when we find bones of animals kept in volcanic ash, rather than mudstones," said Jiang.

The reason the bones were not burned up is that the ash gradually cooled down during its flow. The temperature of the pyroclastic flow was too low to burn up skeletons of animals, Jiang added.