Qualla: Tremp Formation

Tremp Formation: Introduction

Mon, 20 Jul 2026 00:00:00 GMT

Photo credit Tisquesusa, CC BY 4.0. In the red and gray rock around the town of Tremp, you can read the last 300,000 years of the dinosaurs. This band of Pyrenean stone, the Tremp Formation, was laid down across the very end of the Cretaceous and into the age that followed, which means it contains something rare: the Cretaceous-Paleogene boundary, the exact geological line at which the age of dinosaurs ended. Layer by layer, the formation preserves the animals that lived here right up to that moment, more than a thousand dinosaur bones, whole nests of eggs, and trackways pressed into ancient mud. It is one of only a handful of places in Europe where the closing of an entire world is written plainly in the ground.

Read more: Tremp Formation on Qualla

Image: Tisquesusa | CC BY 4.0

Tremp Formation: The Last 300,000 Years

Mon, 20 Jul 2026 00:00:00 GMT

Photo credit Torero at Dutch Wikipedia, CC BY-SA 3.0. What makes the Tremp Formation extraordinary is not just its fossils but its timing. Hadrosaur footprints have been found here in the rock of the final 300,000 years of the Cretaceous, the last stretch before the great extinction, making these among the youngest dinosaur traces i...

Read more: Tremp Formation on Qualla

Image: Torero at Dutch Wikipedia | CC BY-SA 3.0

Tremp Formation: A Dinosaur Nursery in Stone

Mon, 20 Jul 2026 00:00:00 GMT

Photo credit Vila et al., CC BY-SA 4.0. Above all, this is a landscape of eggs. At Basturs, dinosaur nests spread across some 6,000 square meters, the subcircular eggs roughly 20 centimeters across and clustered in groups of four to seven, many preserved exactly where they were laid. The great clutches, some holding mo...

Read more: Tremp Formation on Qualla

Image: Vila et al. | CC BY-SA 4.0

Tremp Formation: A Coast at the End of an Age

Mon, 20 Jul 2026 00:00:00 GMT

Photo credit Ghedoghedo, CC BY-SA 3.0. The dinosaurs of Tremp did not live in a jungle but on a shifting coast. The rock records a continental-to-marine world of estuaries, deltas, river channels, and marshes, where thick clays were laid down across coastal plains and swampy margins turned to beds of lignite. To the s...

Read more: Tremp Formation on Qualla

Image: Ghedoghedo | CC BY-SA 3.0

Tremp Formation: Reading the Rock

Mon, 20 Jul 2026 00:00:00 GMT

Photo credit Tisquesusa, CC BY 4.0. The formation was defined and named in 1968 by the geologist Mey and his colleagues, after the Pre-Pyrenean town of Tremp that gives the whole basin its name. Since then it has drawn universities and researchers from across Europe, and its finds are displayed close to where they ...

Read more: Tremp Formation on Qualla

Image: Tisquesusa | CC BY 4.0