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Lallensack,  J. N., Klein  H., Milàn  J., Wings  O., Mateus  O., & Clemmensen  L. B. (2017).  Sauropodomorph dinosaur trackways from the Fleming Fjord Formation of East Greenland: evidence for Late Triassic sauropods. AbstractWebsite
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Lallensack, J. N., Klein H., Milàn J., Wings O., Mateus O., & Clemmensen L. B. (2017).  Sauropodomorph dinosaur trackways from the Fleming Fjord Formation of East Greenland: Evidence for Late Triassic sauropods. Acta Palaeontologica Polonica. 62(4), 833-843. Abstractlallensack_et_al_2017_-_sauropodomorph_tracks_greenland.pdf

The Late Triassic (Norian–early Rhaetian) Fleming Fjord Formation of central East Greenland preserves a diverse fossil fauna, including both body and trace fossils. Trackways of large quadrupedal archosaurs, although already reported in 1994 and mentioned in subsequent publications, are here described and figured in detail for the first time, based on photogrammetric data collected during fieldwork in 2012. Two trackways can be referred to Eosauropus, while a third, bipedal trackway may be referred to Evazoum, both of which have been considered to represent sauropodomorph dinosaur tracks. Both the Evazoum and the Eosauropus trackways are distinctly larger than other trackways referred to the respective ichnogenera. The trackmaker of the best preserved Eosauropus trackway is constrained using a synapomorphy-based approach. The quadrupedal posture, the entaxonic pes structure, and five weight-bearing digits indicate a derived sauropodiform trackmaker. Other features exhibited by the tracks, including the semi-digitigrade pes and the laterally deflected unguals, are commonly considered synapomorphies of more exclusive clades within Sauropoda. The present trackway documents an early acquisition of a eusauropod-like pes anatomy while retaining a well-developed claw on pedal digit IV, which is reduced in eusauropods. Although unequivocal evidence for sauropod dinosaurs is no older than the Early Jurassic, the present trackway provides evidence for a possible Triassic origin of the group.

Lallensack, J. N., Klein H., Milàn J., Wings O., Mateus O., & Clemmensen L. B. (2017).  Sauropodomorph dinosaur trackways from the Fleming Fjord Formation of East Greenland: evidence for Late Triassic sauropods. Acta Palaeontologica Polonica. 62, 833–843., Number 4 Abstract
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Leal, A. S., Dionísio A., Sequeira Braga M. A., & Mateus O. (2016).  The long term preservation of late jurassic sandstone dinossaur footprints in a museum environment. International Journal of Conservation Science. 7, 627-646., Number 3 Abstract
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Leal, A. A., Dion{\'ısio A., Braga M. A. S., & Mateus O. (2016).  The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment. International Journal of Conservation Science. 7, 627-646. AbstractWebsite

This study focuses on the assessment of the degradation processes occurring in three sandstone infills of fossilized Late Jurassic ornithopod tridactyl footprints, found in 2001 in a coastline cliff in Porto das Barcas (Lourinhã, Portugal) and exhibited in a museum display since 2004. These dinosaur footprints present nowadays severe decay phenomena compromising their physical integrity and are leading gradually to their loss of value. The deterioration patterns were recorded, a map of their distribution was prepared and several samples were collected both in the dinosaur footprints and in the coastline cliff. Different analytical procedures were applied such as XRD, FTIR, FESEM and Ion Chromatography. A microclimatic survey was also performed and air temperature and relative humidity was measured during eight months both indoor and also outdoor. The decay patterns observed are a combination intrinsic and extrinsic factors the stone material, namely swelling of clay minerals in the rock matrix (smectite and chlorite-smectite mixed-layer), presence of salts (mainly chlorides), application of past conservation treatments (poly(vinyl) acetate and epoxy resins) and with the museum’s indoor thermohygrometric conditions (mainly non-stable hygrometric conditions). This scientific knowledge is therefore essential to the sustainable preservation of this paleontological heritage.

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.

Leal, S., Mateus O., Tomás C., & Dionisio A. (2014).  Degradation processes and consolidation of Late Jurassic sandstone dinosaur tracks in museum environment (Museum of Lourinhã, Portugal). EGU General Assembly 2014 - Geophysical Research Abstracts. Vol. 16, EGU2014-9026-1, 2014.leal_et_al_2014_tracks_lab_egu2014-9026-1.pdf
Leal, A. A., Dion\{\'ı\}sio A., Braga M. A. S., & Mateus O. (2016).  The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment. International Journal of Conservation Science. 7, 627-646. Abstract
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Leal, A. A., Dionísio A., Braga M. A. S., & Mateus O. (2016).  The long term preservation of Late Jurassic sandstone dinosaur footprints in a museum environment. International Journal of Conservation Science. 7(3), 627-646. AbstractWebsite

This study focuses on the assessment of the degradation processes occurring in three sandstone infills of fossilized Late Jurassic ornithopod tridactyl footprints, found in 2001 in a coastline cliff in Porto das Barcas (Lourinhã, Portugal) and exhibited in a museum display since 2004. These dinosaur footprints present nowadays severe decay phenomena compromising their physical integrity and are leading gradually to their loss of value. The deterioration patterns were recorded, a map of their distribution was prepared and several samples were collected both in the dinosaur footprints and in the coastline cliff. Different analytical procedures were applied such as XRD, FTIR, FESEM and Ion Chromatography. A microclimatic survey was also performed and air temperature and relative humidity was measured during eight months both indoor and also outdoor. The decay patterns observed are a combination intrinsic and extrinsic factors the stone material, namely swelling of clay minerals in the rock matrix (smectite and chlorite-smectite mixed-layer), presence of salts (mainly chlorides), application of past conservation treatments (poly(vinyl) acetate and epoxy resins) and with the museum's indoor thermohygrometric conditions (mainly non-stable hygrometric conditions). This scientific knowledge is therefore essential to the sustainable preservation of this paleontological heritage.

authors listed, N. (2009).  International Conference on the Geological Collections and Museums: mission and management.. (Brandao J, Callapez P, Mateus O, Castro P, Ed.). , Jan: Journal of Paleontological Techniques 5 (special volume) Abstract
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