by TERRI COOK
This log was lithified — preserving the rings and details of the tree’s anatomy — 39 million years ago. PHOTO/Jean Schnell
Tucked high in the Andes Mountains of northern Peru is a remarkable fossil locality: a 39-million-year-old petrified forest preserved in nearly pristine condition. With its existence unknown to scientists until the early 1990s — and its significance unbeknownst to villagers — this ancient forest hosts the remains of more than 40 types of trees, some still rooted, that flourished in a lowland tropical forest until they were suddenly buried by a volcanic eruption and a series of roiling torrents of mud and debris known as lahars.
These fossils provide an unusually detailed record of neotropical vegetation and climate during the Eocene, a period in Earth’s history when the highest temperatures were about 10 degrees Celsius warmer than today. Such preservation is rare in the New World tropics, as is the close association, anywhere in the rock record, of petrified wood with fossilized leaves.
Since its discovery, scientists and other concerned citizens from Peru to Colorado have been working to study and preserve the spectacular site, now known as El Bosque Petrificado Piedra Chamana, and its unusual and diverse fossils.
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