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Dinosaurs' footprints Praia Grande

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saocampos
saocampos

Praia Grande beach in Sintra, Portugal is known for its dinosaur footprints embedded in the cliffs. Around 125 million years ago during the early Cretaceous period, the area was flat sedimentary plains where dinosaurs like sauropods and theropods left behind footprints as they walked. Over millions of years, the sediments lithified into rock and the landscape was uplifted, resulting in near-vertical cliffs exposing layers with preserved footprints. One clear track shows oval footprints up to 67cm long from a sauropod estimated to be 2.7m tall at the hip and walking at 6-7km/h. Praia Grande continues to reveal evidence of dinosaurs that lived in the area

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Praia Grande Sintra 5 march 2018 Praia Grande Praia Grande is a beach in the municipality of Sintra, Portugal. It is integrated in the Natural Park of Sintra- Cascais. It offers a relatively extensive beach - hence its name. With a strong undulating ideal, the beach is famous for the excellent conditions for surfing and bodyboarding. Every year, this beach is the stage of various water sports events, including the world bodyboard championship. It has an oceanic pool in the extreme north (paid entrance), while to the south there are traces of dinosaur footprints on the cliffs. The water has good quality. Bibliography Santos, V.F. & Cascalho, J.P. (2008) - Geolo- gy of Praia Grande. Roadmap of Discovery. National Museum of Natural History. Mu- seums of the Polytechnic. University of Lis- bon. 23 pp. Santos, V.F. (2008) - Footprints of dinosaurs in Portugal. National Museum of Natural History. Museums of the Polyte- chnic. University of Lisbon. 123 pp. Santos, V. F. (2003) - Dinosaur tracks in the Jurassic -Cretaceous of Portugal. Palaeobiological and paleoecological considerations. PhD Thesis, Fac. Sciences of the Autonomous University of Madrid, 365 pp. (unprecedented). Madeira, J. & Dias, R. (1983) - New tracks of dinosaurs in the lo- wer Cretaceous. Com. Serv. Geol. Portugal, 69: 147-158.
The sedimentary strata surrounding the Sintra mountain range have variable slopes. Here, one of the surfaces of the almost vertical limestone layers reveals quite deep dinosaur tracks. It is a testimony of the passage of dinosaurs about 125 million years ago, when the Sintra mountain range did not exist yet and the sediments that now constitute the more or less inclined sedimentary strata that surround it were accumulating. In these times, layers of sediments were accumulated horizontally, which contained remains of organisms such as bivalves and gastropods. Over millions of years the accumulated sediments have become sedimentary rocks, the organic remains in fossils and the horizontal planes in planes with varied and often folded and fractured slopes. The forces generated inside the Earth allowed the Sintra mountain range and other reliefs to form, dragging with their movement the rocks of the Earth's crust. Hence, nowadays, we can see, in layers of vertical rocks, deep footprints that resulted from the force exerted by the feet of the animals in the muddy, flat and horizontal soil. These testimonies help us understand the geological time, measured in millions of years, during which profound transformations have occurred both in organisms and on the earth's surface. Dinosaur Legs Age: 125 Ma (lower Cretaceous) Types of Fossils: Footprints (prints) - Ichnosophils Dinosaurs: Sauropods, Theropods and Ornithopods The following stand out: • Impressions of finger sauropod feet • A track of a sauropod with about 2.7 m from the ground to the hip that would be moving at about 6-7 km / h. • Evidence of carnivores about 2.5 m from the ground to the hip and that would be moving at about 1.5 to 2 km / h. Two practically vertical layers with dinosaur footprints constitute the icnotopo of Praia Grande (Lower Cretaceous, Sintra). On a level with dynoturbation, there is a layer (delimited for better recognition) with differentiated footprints. When you climb the staircase that connects the southern zone of Praia Grande to the top and reach the place where the stairs are parallel to the lower part of the vertical slab, you can see a track consisting of oval impressions that correspond to the marks of feet and others, smaller and crescent, left by the hands of a sauropod. The most well-preserved footmarks are about 67 cm long by 60 cm wide and on the left side fingerprints are directed towards the outside of the runway. One of these marks has a depth of 25 cm. Footprints on the right side are oval. The hand marks are smaller, about 30 cm wide by about 15 cm long. In this track, the area of the marks of the feet is about six times the area of the marks of hands. This track has an internal width of about 55 cm. The size of the step is 3.3 m and was obtained for the left foot because its footprints are the clearest. Taking into account the footprints were recorded three consecutive step values ranging between 1.6 and 2 m. This sauropod would have about 2.7 m from the ground at hip and it is estimated that it would be moving at about 6-7 km/h.

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Dinosaurs' footprints Praia Grande

  • 1. Praia Grande Sintra 5 march 2018 Praia Grande Praia Grande is a beach in the municipality of Sintra, Portugal. It is integrated in the Natural Park of Sintra- Cascais. It offers a relatively extensive beach - hence its name. With a strong undulating ideal, the beach is famous for the excellent conditions for surfing and bodyboarding. Every year, this beach is the stage of various water sports events, including the world bodyboard championship. It has an oceanic pool in the extreme north (paid entrance), while to the south there are traces of dinosaur footprints on the cliffs. The water has good quality. Bibliography Santos, V.F. & Cascalho, J.P. (2008) - Geolo- gy of Praia Grande. Roadmap of Discovery. National Museum of Natural History. Mu- seums of the Polytechnic. University of Lis- bon. 23 pp. Santos, V.F. (2008) - Footprints of dinosaurs in Portugal. National Museum of Natural History. Museums of the Polyte- chnic. University of Lisbon. 123 pp. Santos, V. F. (2003) - Dinosaur tracks in the Jurassic -Cretaceous of Portugal. Palaeobiological and paleoecological considerations. PhD Thesis, Fac. Sciences of the Autonomous University of Madrid, 365 pp. (unprecedented). Madeira, J. & Dias, R. (1983) - New tracks of dinosaurs in the lo- wer Cretaceous. Com. Serv. Geol. Portugal, 69: 147-158.
  • 2. The sedimentary strata surrounding the Sintra mountain range have variable slopes. Here, one of the surfaces of the almost vertical limestone layers reveals quite deep dinosaur tracks. It is a testimony of the passage of dinosaurs about 125 million years ago, when the Sintra mountain range did not exist yet and the sediments that now constitute the more or less inclined sedimentary strata that surround it were accumulating. In these times, layers of sediments were accumulated horizontally, which contained remains of organisms such as bivalves and gastropods. Over millions of years the accumulated sediments have become sedimentary rocks, the organic remains in fossils and the horizontal planes in planes with varied and often folded and fractured slopes. The forces generated inside the Earth allowed the Sintra mountain range and other reliefs to form, dragging with their movement the rocks of the Earth's crust. Hence, nowadays, we can see, in layers of vertical rocks, deep footprints that resulted from the force exerted by the feet of the animals in the muddy, flat and horizontal soil. These testimonies help us understand the geological time, measured in millions of years, during which profound transformations have occurred both in organisms and on the earth's surface. Dinosaur Legs Age: 125 Ma (lower Cretaceous) Types of Fossils: Footprints (prints) - Ichnosophils Dinosaurs: Sauropods, Theropods and Ornithopods The following stand out: • Impressions of finger sauropod feet • A track of a sauropod with about 2.7 m from the ground to the hip that would be moving at about 6-7 km / h. • Evidence of carnivores about 2.5 m from the ground to the hip and that would be moving at about 1.5 to 2 km / h. Two practically vertical layers with dinosaur footprints constitute the icnotopo of Praia Grande (Lower Cretaceous, Sintra). On a level with dynoturbation, there is a layer (delimited for better recognition) with differentiated footprints. When you climb the staircase that connects the southern zone of Praia Grande to the top and reach the place where the stairs are parallel to the lower part of the vertical slab, you can see a track consisting of oval impressions that correspond to the marks of feet and others, smaller and crescent, left by the hands of a sauropod. The most well-preserved footmarks are about 67 cm long by 60 cm wide and on the left side fingerprints are directed towards the outside of the runway. One of these marks has a depth of 25 cm. Footprints on the right side are oval. The hand marks are smaller, about 30 cm wide by about 15 cm long. In this track, the area of the marks of the feet is about six times the area of the marks of hands. This track has an internal width of about 55 cm. The size of the step is 3.3 m and was obtained for the left foot because its footprints are the clearest. Taking into account the footprints were recorded three consecutive step values ranging between 1.6 and 2 m. This sauropod would have about 2.7 m from the ground at hip and it is estimated that it would be moving at about 6-7 km/h.