Ash preserves fossils like dried plums in China.

450-mph Pompeii-type volcano blasts created exquisite dinosaur fossils

 

In the northeast of China, at the Yixian and Jiufotang formations, scientists have discovered thousands of exquisitely preserved fossils of plants and birds, dinosaurs and mammals. Together they make up the Jehol Biota -- an ecosystem, preserved in ash, that dates back nearly 130 million years.

 

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