large sections of a petrified log

Petrified wood represents trees once alive over 200 million years ago.

Photo by Marge Post/NPS

Fossils are clues to the past, allowing researchers to reconstruct ancient animals and plants. Together with the surrounding rocks, fossils tell the stories of ancient ecosystems.

Petrified Forest has plant and animal fossils representing the Late Triassic, going back over 200 million years. The Triassic Period is sometimes referred to as the "Dawn of the Dinosaurs" because it is the time before the Jurassic Period when dinosaurs ruled the earth.

Fossils can be big - some petrified logs found in the park measure over 190 feet - or small - a single tooth less than an inch long may contain the definitive characteristic of a new species.

clam fossils

Clam fossils from the Triassic Period indicate a waterway within the ancient environment.

Photo by Marge Post/NPS

Every fossil found is like a piece in a jigsaw puzzle. Imagine putting together a jigsaw puzzle without knowing what the completed puzzle will look like. That would be hard, but what if you also didn't have all the pieces?

Context is very important with fossils. Where a fossil is found, what else it is found with, and how it was preserved are clues just as important as the fossil itself. Every fossil found in the park is important because of its context. The context tells its story. When visiting the park, enjoy the petrified wood, but leave it where you find it.

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