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Polcyn, M. J., Jacobs L. L., Strganac C., Mateus O., Myers T. S., May S., Araújo R., Schulp A. S., & Morais M. L. (2014).  Geological and paleoecological setting of a marine vertebrate bonebed from the Lower Maastrichtian at Bentiaba, Angola. Secondary Adaptation of Tetrapods to Aquatic Life. , 2-4 Jun 2014, Washington DC, USA
Mateus, O. (2014).  Geological and paleoecological setting of a marine vertebrate bonebed from the Lower Maastrichtian at Bentiaba, Angola. Proceedings of the Secondary Adaptation of Tetrapods to Aquatic Life. NA., 1 Abstract

A single, geographically and temporally restricted horizon at Bentiaba, Angola (14.3° S), preserves a concentration of skeletons and isolated elements representing sharks, rays, bony fish, at least three species of turtles, two species of plesiosaurs, at least five species of mosasaurs, and rare volant and terrestrial forms. The concentration, referred to as the Bench 19 Fauna, formed on a narrow continental shelf at paleolatitude 24°S as predicted by paleomagnetic data and confirmed by plate motion models. The shelf evolved as a transform passive margin along faults associated with the opening of the South Atlantic. Latitude 24°S falls today along the coast of northern Namibia, an area of intense upwelling and hyperarid coastal desert. The Namibe Basin in southern Angola is separated from the Walvis Basin of Namibia by the Walvis Ridge, and the continental shelf in northern Namibia is eight times the width of that at Bentiaba. However, the sediment entombing the fossils at Bentiaba is an immature feldspathic sand, shown by detrital zircon ages to be derived from nearby exposed granitic shield rocks, suggesting similar climatic and drainage conditions between the two regions. Temporal control of the Bentiaba section is provided by magnetostratigraphy and stable carbon isotope chemostratigraphy anchored by an Ar40/Ar39radiometric date on basalt. The age of Bench 19 is constrained to chron C32n.1n and thus falls between 71.4 and 71.64 Ma. Massive bedding without hummocky cross-bedding or other sedimentary structures indicates deposition in shallow water below wave base. δ18O analysis of bivalve shells indicates a water temperature of 18° C immediately below Bench 19. Nearest neighbor distance peaks at 5 m (n=19

Strganac, C., Jacobs L., Polcyn M., Mateus O., Myers T., Araújo R., Fergunson K. M., Gonçalves A. O., Morais M. L., Schulp A. S., da Tavares T. S., & Salminen J. (2015).  Geological Setting and Paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola. Netherlands Journal of Geosciences. 94(1), 121-136. Abstractstrganac_et_al_2014_geological_setting_bentiaba_angola.pdfWebsite

The Bench 19 Bonebed at Bentiaba, Angola, is a unique concentration of marine vertebrates preserving six species of mosasaurs in sediments best correlated by magnetostratigraphy to chron C32n.1n between 71.4 and 71.64 Ma. The bonebed formed at a paleolatitude near 24°S, with an Atlantic width at that latitude approximating 2700 km, roughly half that of the current width. The locality lies on an uncharacteristically narrow continental shelf near transform faults that controlled the coastal outline of Africa in the formation of the South Atlantic Ocean. Biostratigraphic change through the Bentiaba section indicates that the accumulation occurred in an ecological time dimension within the 240 ky bin delimited by chron 32n.1n. The fauna occurs in a 10 m sand unit in the Mocuio Formation with bones and partial skeletons concentrated in, but not limited to, the basal 1–2 m. The sediment entombing the fossils is an immature feldspathic sand shown by detrital zircon ages to be derived from nearby granitic shield rocks. Specimens do not appear to have a strong preferred orientation and they are not concentrated in a strand line. Stable oxygen isotope analysis of associated bivalve shells indicates a water temperature of 18.5°C. The bonebed is clearly mixed with scattered dinosaur and pterosaur elements in a marine assemblage. Gut contents, scavenging marks and associated shed shark teeth in the Bench 19 Fauna indicate biological association and attrition due to feeding activities. The ecological diversity of mosasaur species is shown by tooth and body-size disparity and by δ13C analysis of tooth enamel, which indicate a variety of foraging areas and dietary niches. The Bench 19 Fauna was formed in arid latitudes along a coastal desert similar to that of modern Namibia on a narrow, tectonically controlled continental shelf, in shallow waters below wave base. The area was used as a foraging ground for diverse species, including molluscivorus Globidens phosphaticus, small species expected near the coast, abundant Prognathodon kianda, which fed on other mosasaurs at Bench 19, and species that may have been transient and opportunistic feeders in the area.

Strganac, C., Jacobs L. L., Polcyn M. J., Mateus O., Myers T. S., Salminen J., May S. R., Araújo R., Ferguson K. M., Gon?alves A. O., Morais M. L., Schulp A. S., & da Silva Tavares T. (2014).  Geological setting and paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94, 121-136., Number 1 Abstract
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Polcyn, M., Jacobs L., Strganac C., Mateus O., Myers S., May S., Araujo R., Schulp A., & Morais M. (2014).  Geology and paleoecology of a marine vertebrate bonebed from the lower Maastrichtian of Angola. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 206.polcyn_et_al._2014_geology_and_paleoecology_of_a_marine_vertebrate_bonebed_from_the_lower_maastrichtian_of_angola.pdf
Pereira, B., Mateus O., Kullberg J. C., & Rocha R. (2017).  The geotouristic potential of the Oeste Region of Portugal. 14th European Geoparks Conference | Abstracts Book 167. 167., Ponta Delgadapereira_et_al_2017_geotouristic_oeste.pdf
Pereira, B., Mateus O., Kullberg J. C., & Rocha R. (2017).  The geotouristic potential of the Oeste Region of Portugal. Abstract
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Mateus, O. (2014).  Gigantic Jurassic predators. 52 Things You Should Know About Palaeontology. 56-57.: Agile Libremateus_2014_gigantic_jurassic_predators.pdf
Mateus, O. (2014).  Gigantic jurassic predators. (Agile Libre, Ed.).52 Things You Should Know About Palaeontology. 56–57.: Agile Libre Abstract
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Hayashi, S., Redelstorff R., Mateus O., Watabe M., & Carpenter K. (2014).  Gigantism of stegosaurian osteoderms. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 145.hayashi_et_al_2014_gigantism_of_stegosaurian_osteoderms.pdf
Mateus, O. (2014).  Gigantism of stegosaurian osteoderms. Journal of Vertebrate Paleontology. Program and Abstracts, 2014, 145.: Taylor & Francis Abstract
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