Allen Formation

The Allen Formation is a geological layer in Neuquén Province containing sedimentary rocks with fossilized remains of dinosaurs and other animals from the Late Cretaceous period. The deposits consist of clay and sandstone with limestone and mineral-rich layers.

The formation was scientifically described and named in 1981 based on rock sequences studied in Bajo de Añelo. It shows that this region was a warm, shallow sea with river systems about 70 million years ago.

Fossil sites here attract paleontologists from around the world who work together on excavations and share their findings. The location serves as an important meeting point for experts studying dinosaur-era life.

Visitors need permits and expert guidance to reach and explore the fossil sites. The best time to visit is during drier months when roads are reliably accessible.

A notable find here was a pterosaur named Aerotitan, the first of its kind discovered in South America. This discovery changed scientists' understanding of how these flying reptiles were distributed.

Location: Neuquén Province

GPS coordinates: -40.00000,-66.60000

Latest update: December 10, 2025 15:56