|mhorn||Дата: Sunday, 07.07.2013, 22:16 | Сообщение # 1|
|Loureiro I.M., Cabral M.C., Duarte L.V., Azerêdo A.C. (2013) Ostracodos do Sinemuriano superior da região de S. Pedro de Moel e de Peniche: relação com o contexto sedimentar // Comunicações Geológicas, 100, Especial I, 49-54 |
The aim of this study was to understand the ostracod distribution in the Upper Sinemurian–lowermost Pliensbachian of S. Pedro de Moel region (top of the Coimbra and Água de Madeiros formations) and Peniche (Polvoeira Member of the Água de Madeiros Formation). At S. Pedro de Moel 39 samples were studied; 4099 ostracods were found and distributed into 32 taxa. The most common are Ogmoconchella celticensis Ainsworth, 1989 and Polycope cf. cerasia Blake, 1876. The ostracods reveal an increasing water depth, from brackish to slightly marine at the bottom to open marine at the top, where no benthic forms were recovered. At Peniche, 10 samples were studied, all of which had poorly preserved ostracods, in a total of 753 individuals distributed into 22 taxa. The most abundant are Liasina cf. lanceolata Apostolescu, 1959 and Ektyphocythere aff. sinemuriana (Ainsworth, 1989). The depositional environment of the Peniche succession would have been more dynamic and oxygenated than the one from S. Pedro de Moel region.
Middle Jurassic - Lower Cretaceous ammonites & aptychi