Tracks - Footprints

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Leal, A. S., Mateus O., Tomás C., & Dionísio A. (2014).  Decay and conservation trial of Late Jurassic sandstone with dinosaur tracks in a museum environment (Museum of Lourinhã, Portugal). Buletini i Shkencave Gjeologjike. 1(2014), 410. Abstractleal_et_al_2014_cbgassav1-_abstract_dinosaur_footprints__page_410.pdf

Abstract
Late Jurassic dinosaur footprints were found on a coastline cliff in Lourinhã, Porto das Barcas, Lagido do Forno (coordinate 39°14.178’N, 9°20.397’W, Portugal) in June 2001. The locality is characterized by steep cliffs with high slopes that are composed of gray and red sandstones/ siltstones. The location belongs to the successions of Lusitanian Basin representing the Porto Novo Member of the Lourinhã Formation. Three natural infills of tridactyl tracks, possibly ascribed to ornithopod, a bipedal herbivore were found, representing a left foot movement, a right and a left one, respectively. Footprints are 300- 400mm wide and have a height of 330-360mm. The footprints are characterized by round fingers, which are elongated due to some degradation/ erosion. The footprints were collected from the field in 2001 and subsequently cleaned, consolidated and glued in the laboratory of the Museum of Lourinhã before being exhibited in a museum display. Stone matrix was removed and a consolidation product was applied, probably a polyvinyl acetate. The footprint with broken central digit was glued with an epoxy resin, Araldite. Both applied products were confirmed by analysis of μ- FTIR and both presented colour change and detachment surface problems. The footprints have been exposed in the palaeontology hall of the Museum of Lourinhã, Portugal from 2004 without climate controlling. These trace fossils form an important part of the palaeontological collection of Late Jurassic vertebrate fossils from Lourinhã Formation. Presently, it is considered a unique heritage in danger of disappearing due to high decay level of disaggregation of its geological structure. The footprints display several pathologies, such as “Blistering”, “Powdering”, “Exfoliation”’ as well as “Dirt”, “Fracture”’, “Inscriptions”, “Consolidants” and “Adhesives” and are now in very poor conditions. Laboratorial analysed were made to evaluate the presence of salts. Moreover a microclimatic study was conducted inside the museum to evaluate the influence of thermo-hygrometric parameters on the decay processes. The future interventions will depend on the results of consolidation trials that are currently under progress by using stone samples taken from the same layer and location from Porto das Barcas applying different commercial consolidation products.

Mateus, O. (2012).  New dinosaur and pterosaur tracksites from the Late Jurassic of Portugal. , Chongqing, China: 2012 Abstract Book of Qijiang International Dinosaur Tracks Symposium Abstractmateus_2012_dinosaur_tracks_portugal__abstract_book_qijiang_int_dinosaur_tracks_symposium.pdf

Portugal is rich on dinosaur remains (bones, eggs, and tracks) from Early Jurassic to Late
Cretaceous ages, but mainly from the Late Jurassic, in which dozen of tracksites have been reported.
Here are reported new or poorly known track localities:
1) Five tracksites share the preservation substrate (marine carbonated limestone), age (late Jurassic), geographic area (Leiria district of Portugal), kind of preservation (true tracks), and completeness (trackways of multiple individuals):
i) Praia dos Salgados includes eight trackways, mostly ornithopods and theropods, and one wide gauge sauropod, made in very soft sediment; some preserve the hallux impression.
ii) Serra de Mangues is mostly covered with vegetation but seems to include dozens of tracks comprising theropods, thyreophorans, ornithopods and sauropods.
iii) Sobral da Lagoa (Pedreira do Rio Real) include six trackways but poorly preserved;
and
iv) Serra de Bouro that preserves four sauropod trackways in one single layer.
v) Pedrógão, preserved, at least, one theropod trackway and several isolated tracks of
theropods and ornithopods were found in different layers in the Early Oxfordian.
2) The locality in Praia de Porto das Barcas yielded natural casts of stegosaur tracks
(including pes print with skin impression) and a very large sauropod pes print with about
1.2 m long pes.
3) A new pterosaur tracksite was found in the Late Jurassic of Peralta, Lourinhã (Sobral Member, Lourinhã Fm.; Late Kimmeridgian/Early Tithonian). More than 220 manus and pes tracks have been collected in about five square meters, all ascribed to pterosaurs. The tracks were produced in a thin mud layer that has been covered by sand which preserved them as sandstone mould infill (natural casts). The manus of the largest specimens is 13 cm wide and 5.5 cm long and the pes measures 14.5 cm in length and 9 cm in width. This shows the occurrence of very large pterosaurs in the Late Jurassic. Other pterosaur tracksites in the Late Jurassic of Portugal are: Porto das Barcas (Lourinhã Municipality), South of Consolação (Peniche Municipality), and Zambujal de Baixo (Sesimbra Municipality).

Mateus, O., & Milàn J. (2011).  New dinosaur and pterosaur tracksites from the Late Jurassic of Portugal. Dinosaur Tracks 2011 An International Symposium, . , 14-17 April, 201, Obernkirchen, Germany: Universität Göttingenmateus__milan_2012_new_dinosaur_and_pterosaur_tracksites_from_the_late_jurassic.pdf
Mateus, O., Milàn J., Romano M., & Whyte M. A. (2011).  New finds of stegosaur tracks from the Upper Jurassic Lourinhã Formation, Portugal. Acta Palaeontologica Polonica. 56(1), 651-658. Abstractmateus_et_al_2011_-_deltapodus_with_skin_impressions_from_portugal.pdf

Eleven new tracks from the Upper Jurassic of Portugal are described and attributed to the stegosaurian ichnogenus Deltapodus. One track exhibits exceptionally well−preserved impressions of skin on the plantar surface, showing the stegosaur foot to be covered by closely spaced skin tubercles of ca. 6 mm in size. The Deltapodus specimens from the Aalenian of England represent the oldest occurrence of stegosaurs and imply an earlier cladogenesis than is recognized in the body fossil record.

Mateus, O., & Milan J. (2010).  First records of crocodyle and pterosaur tracks in the Upper Jurassic of Portugal.. New Mexico Museum of Natural History and Science Bulletin. 51, 83-87., Jan Abstractmateus_and_milan_2010_portugal_first_records_of_crocodyle_and_pterosaur_tracks_in_the_upper_jurassic_of_portugal.pdfWebsite

The Upper Jurassic of Portugal has a rich vertebrate fauna well documented from both body and trace fossils. Although the occurrence of crocodyles and pterosaurs is well documented from body fossils, trace fossils from both groups were unknown until now. Here we describe an isolated crocodyle-like track from Praia da Peralta and pterosaur tracks from the Kimmeridgian of Pedreira do Avelino, Sesimbra (Azóia Fm.) and Porto das Barcas, Lourinhã (Lourinhã Fm.). An enigmatic track suggests the possible presence of a small, tail-dragging tetrapod.
Possible track-makers are suggested based on the known Late Jurassic vertebrate fauna of Portugal.

Mateus, O., & Milan J. (2010).  A diverse Upper Jurassic dinosaur ichnofauna from central-west Portugal. Lethaia. 43, 245–257., Jan Abstractmateus__milan_2010_-_diverse_l_j_ichnofauna_from_lourinha_fm_portugal.pdfWebsite

A newly discovered dinosaur track-assemblage from the Upper Jurassic Lourinha˜ Formation (Lusitanian Basin, central-west Portugal), comprises medium- to large-sized sauropod tracks with well-preserved impressions of soft tissue anatomy, stegosaur tracks and tracks from medium- to large-sized theropods. The 400-m-thick Lourinha˜ Formation consists of mostly aluvial sediments, deposited during the early rifting of the Atlantic Ocean in the Kimmeridgian and Tithonian. The stratigraphic succession shows several shifts between flood-plain mud and fluvial sands that favour preservation and fossilization of tracks. The studied track-assemblage is found preserved as natural casts on the underside of a thin bivalve-rich carbonate bed near the Tithonian–Kimmeridgian boundary. The diversity of the tracks from the new track assemblage is compared with similar faunas from the Upper Jurassic of Asturias, Spain and the Middle Jurassic Yorkshire Coast of England. The Portuguese record of Upper Jurassic dinosaur body fossils show close similarity to the track fauna from the Lourinha˜ Formation.

Mateus, O., & Milan J. (2008).  Ichnological evidence for giant ornithopod dinosaurs in the Upper Jurassic Lourinhã Formation, Portugal. Oryctos. 8, 47-52. Abstractmateus_and_milan_2008_ichnological_evidence_for_giant_ornithopod_big_ornithopod_track_from_u_j_lourinha_fm_portugal.pdfWebsite

The Upper Jurassic Lourinhã Formation (Lusitanian Basin, Portugal) contains a diverse dinosaur fauna comprising theropods, sauropods, stegosaurs, ankylosaurs and several genera of ornithopods. The sedimentology in the area favours preservation of tracksways, and tracks from most of the dinosaurs are also represented by skeletal remains. During fieldwork in the summer of 2003 a new, large, tridactyl track was found at the beach of Vale Frades, approximately 6 km north of Lourinhã (central west Portugal). The track was found together with a stegosaur track on a clay bed exposed within the intertidal zone. Due to the immediate danger of erosion, the track was collected and is now on display at Museu da Lourinhã. The track is 70 cm long and 69 cm wide, the toes are short and broad, with indications of short blunt claws, and there is a high angle of divarication between the outer digits. The shape and dimensions of the track identifies it as deriving from an ornithopod dinosaur with an estimated hip height around three metres. Although very large ornithopods are known from the Cretaceous, the largest known Jurassic ornithopod is Camptosaurus from North America, and the largest known from Portugal is the camptosaurid Draconyx loureiroi. Neither of these reached the body size suggested by the new track. So far the track described herein is the only evidence for a Jurassic ornithopod of that size.

Mateus, O., & Milan J. (2008).  Sauropod forelimb flexibility deduced from deep manus tracks. 52th Paleontological Association Annual Meeting. 18th-21st December 2008,. 67-68.: University of Glasgow Abstractmateus__milan_2008_palass_sauropod_forelimb_flexibility_deduced_from_deep_manus_tracks.pdf

Sauropods are often considered to have very limited mobility and reduced limb flexibility, mainly due to their giant size and consequent weight. In the Upper Jurassic Lourinhã Formation, central-west Portugal, deep vertical natural casts of sauropod manus tracks are often preserved as the infills of the original tracks. These manus tracks are vertical-walled, with marks of the striations of the skin scales, showing that the movement of the sauropod manus impacting and exiting the mud was totally vertical with no horizontal component of the stride. Some tracks are up to 66 cm deep, which is equivalent to the height of whole sauropod manus. This means that sauropods could lift their anterior feet in a complete vertical manner. Such movement is only possible if there is mobility at elbow and shoulder articulations in a higher degree than previously thought for sauropods. Our vision of sauropod limbs as inflexible columns has to be updated to a more dynamic model for limbs and body.

Milan, J., Christiansen P., & Mateus O. (2005).  A three-dimensionally preserved sauropod manus impression from the Upper Jurassic of Portugal: Implications for sauropod manus shape and locomotor mechanics. Kaupia. 14, 47-52. Abstractmilan_et_al_mateus_2005_-_3d_sauropod_manus_track_l_j_portugal.pdfWebsite

Sauropods were the largest animals ever to walk the earth, and evolved several specializations in their limbs in order to support their body mass. Their legs became columnar and their manual digits became reduced and encapsulated in tissue to form a single weight-bearing unit in the derived sauropods. A new three-dimensionally preserved cast of a sauropod manus, found in the Upper Jurassic Lourinhã Formation, Portugal, demonstrates not only the shape, but also the actual movements of the sauropod manus during the stride. The manus cast is 32 cm deep, and show the manus to be hoof-shaped and lacking any impressions of individual digits, except for digit I, the pollex. Well preserved striations from skin on the sides of the cast show that the manus was covered in rough, tubercular skin. The width of the manus cast is consistent from top to bottom, demonstrating that the manus was brought down and lifted vertically before any parasaggital movement of the upper limb took place.

Mateus, O., & Milan J. (2005).  Ichnological evidence for giant ornithopod dinosaurs in the Late Jurassic Lourinhã Formation, Portugal.. Abstract Book of the International Symposium on Dinosaurs and Other Vertebrates Palaeoichnology. 60., Fumanya, Barcelona Abstractmateus__milan_2005_footprint.pdf

The Late Jurassic Lourinhã Formation contains a diverse dinosaur fauna comprising theropods, sauropods, stegosaurs, ankylosaurs and several genera of ornithopods.
The sedimentology in the area favours preservation of footprints, and footprints from most of the dinosaurs represented by skeletal remains are present in the area. During fieldwork in the summer of 2003 a new, large, tridactyl footprint was found at the beach of Vale Frades, approximately 6 km north of Lourinhã, Portugal. The footprint was found together with a stegosaur footprint on a clay bed exposed within the tidal zone. The footprints were preserved as sandstone casts standing on a pedestal of clay. This unusual type of preservation is the result of the footprints having first been emplaced in clay, and then filled with sand. During the present day erosion from the sea, the harder sandstone cast of the footprints protects the subjacent clay layers from erosion. Owing to the immediate danger of erosion of, the footprint was collected and is now on display at Museu da Lourinhã (ML 1000). The footprint is 70 cm long and 69 cm wide, the toes are short and broad, with indications of short blunt claws. The

divarication angle between the outer digits is close to 90 degrees. The dimensions and general

morphology of the footprint identifies it as deriving from an ornithopod dinosaur with an estimated hip height of 4.13 metres. Although very large ornithopods are known from the Cretaceous, the largest known Jurassic ornithopod is Camptosaurus from USA, and the largest known from Portugal is the camptosaurid Draconyx loureiroi. Neither of these reached the body size suggested by the new footprint. So far the footprint described herein is s the only evidence for a Jurassic ornithopod of that size.