"We may have dinosaur eggs here and we may even have crocodile eggs," geologist Pedro Proença e Cunha, a full professor at the Department of Earth Sciences at the University of Coimbra, told Lusa.

Specialist in stratigraphy and sedimentology, Pedro Proença e Cunha studied dinosaur eggs found in Lourinhã, some with preserved embryos.

The geological layers which make up the cliffs of Cabo Espichel reveal, to the geologist's eye, the potential to find bones and eggs of animals which 129 million years ago left the footprints that researchers are following today.

Proving this are several bones and distinct fossils already found over years of research. In the present campaign, the researcher found a dinosaur humerus (a small theropod) near the spot where palaeontologist Silvério Figueiredo discovered other fragments of prehistoric animals; dinosaurs, crocodiles and fish.

"The marl has the potential not only to have bones, but, for example, to have eggs," he exemplified, pointing to the rock formations surrounding the site under exploration.

"Regarding the geological component, there is a unique exhibition here, I would say in the world! It is classified and worth being enjoyed by a wide public, not only nationally, but also internationally. But avoiding destruction", he defended.

So that the site, the richness of the landscape inserted in a protected area and the heritage it contains can be enjoyed by the public in general, the geologist considered that "some preparation" will be necessary, in order to guide visits with guides and avoid the appearance of "fossil hunters".

Disclosing the finds without running the risk of seeing this heritage destroyed is always "a delicate balance", he assumed.

The place where the researchers are working today was 129 million years ago a lagoon with a dry tropical climate, frequented by animals weighing tons, herbivores and carnivores, which left their imprints in various layers and at different times.

The transformations that the Earth has undergone, with "the raising of the Arrábida chain" and the "sapa erosion" caused by the sea have given rise to the cliffs that today appear as "leaves of time" to the geologist's eyes.

Water courses existing on the site also contribute to the erosion and to expose different layers of sediments in which the specialist identifies climates, fauna and flora.

"We've identified various types of footprints, both dinosaur, and new ones, crocodile, and in other cases we can find gastropods, as well as other types of fossils. All this helps us to situate", he said.

Through the footprints the researchers hope to be able to identify the animals that produced them, their weight, tracks and behaviour, and in some cases the work is made difficult by the abundance of footprints of different species, some in overlapping.