Research press release


Nature Communications

Geology:‘Animal Pompeii’ preserved in China



今回、Baoyu Jiangたちは、いくつかの重要な地層で化石鳥類と化石恐竜類の試料を収集し、それらの試料と試料が保存されていた堆積物を分析した。その結果、それぞれの骨格化石が火砕流に直接埋め込まれていたことが判明した。火砕流とは、一部の爆発的火山噴火に伴って生じる高温のガスと岩石の流れで、流速が極めて大きい。動物化石は、特徴的な埋没姿勢をとっており、炭化の証拠も見られ、イタリア・ポンペイでの火山噴火の犠牲者に見られる特徴に似ていた。この新知見は、火砕流から大量死、埋没、輸送、そして、最終的な熱河生物相の保存に至ったことを示唆している。


The curious juxtaposition of exceptionally preserved dinosaurs, mammals and early birds found together in the Yixian and Juifotang rock formations in northern China is the result of lethal volcanic flows, according to a study published in Nature Communications. The finding helps to untangle the mystery behind the preservation history of the Jehol Biota - an ancient ecosystem of northern China, around 130 to 120 million years ago.

During this period, a mix of dinosaurs, mammals, early birds and lizards lived in a landscape of lakes and conifer forests, surrounded by volcanoes. Today these animals are found as incredibly well-preserved fossils in mixed graveyards in northern China, yet the cause of these mass mortalities and their preservation history remains a mystery.

Baoyu Jiang and colleagues collected samples from fossil birds and dinosaurs from several key locations and analysed them and the sediments in which they were preserved. The team found that each of the skeletons had been directly embedded within pyroclastic flows, incredibly fast moving currents of hot gas and rock that accompany some explosive volcanic eruptions. Each of the preserved animals was characterised by entombment poses and showed evidence of charring, similar to those associated with victims at Pompeii, Italy. The findings suggest that pyroclastic flows led to the mass mortality, entombment, transportation and ultimate preservation of the Jehol Biota.

Pyroclastic flows are lethal, have occurred throughout time and, based on these findings, the authors suggest that such flows could be responsible for the preservation of other fossil groups that are closely associated with ash deposits.

doi: 10.1038/ncomms4151

「Nature 関連誌注目のハイライト」は、ネイチャー広報部門が報道関係者向けに作成したリリースを翻訳したものです。より正確かつ詳細な情報が必要な場合には、必ず原著論文をご覧ください。

メールマガジンリストの「Nature 関連誌今週のハイライト」にチェックをいれていただきますと、毎週最新のNature 関連誌のハイライトを皆様にお届けいたします。