Jach, R., Machaniec, E. & Uchman, A. 2011: The trace fossil Nummipera eocenica from the Tatra Mountains, Poland: morphology and palaeoenvironmental implications. Lethaia, Vol. 45, pp. 342–355. The tubular trace fossil Nummipera eocenicaHölder 1989 occurs in a single stratigraphical horizon in Eocene nummulitic limestones of the Tatra Mountains, Poland. The wall of N. eocenica is built of Discocyclina and Nummulities (larger foraminifera) tests, very rarely of the Ditrupa (Polychaeta) tube fragments, bivalve shell fragments, echinoid spines and coralline algae. Morphotype are distinguished on the basis of wall composition and structure. Morphotype A is dominated by fusiform Discocyclina tests, which were preferentially selected by the trace makers for construction of a well‐constructed and resistant wall. Morphotype B contains more robust tests of Nummulites, while morphotype C is dominated by saddle‐shaped tests of Discocyclina. Nummipera eocenica was produced during a period of seafloor stabilization caused by a deepening. The succession of the morphotypes B, A reflects diminishing energy and increasing water depth. Probably morphotype C represents even lower energy environment than morphotype A. The trace fossil is interpreted as a domichnion, which wall was constructed for protection. The trace maker can be considered between polychaetes and crustaceans; however, comparisons to the closest recent analogues, the polychaete Diopatra cuprea or alpheid shrimps, are not satisfactory. □Bartonian, burrow, Carpathians, large foraminifera, trace fossils.

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The Sirte Basin is located in the north-central part of Libya (Fig. 1). It is a basin characterized by a series of platforms and deep troughs containing several oil and gas fields. Depositional history of the Sirte Basin started in the Early Cretaceous time, which has been related to the tectonic evolution of the North African passive continental margin. The history of the Sirte Basin had been spanning the Cretaceous and Palaeogene times. It had been influenced by several marine transgressions and several rifting phases induced by the deformation of the North African continental margin. The relative sea-level changes and the tectonics might have greatly influenced the accomodation space, especially over the Western Sirte Basin (WSB) during the Palaeogene.Because of the numerous oil and gas fields, the geological history of the WSB was the subject of numerous stud-

Latest Eocene plant macrofossils and trace fossils collected a century ago by Wiktor Kuźniar are revised and their stratigraphical and palaeoecological meaning is re-considered. They derive from marine limestones and marls cropping out on the northern slope of the Hruby Regiel mountain in the Western Tatra Mountains. Leaves belonging to the families Fagaceae and Lauraceae and fruits of the palm Nypa are recognized. The co-occurrence of the planktonic foraminifer taxa Chiloguembelina cf. gracillima and Globigerinatheca cf. index and fruits of Nypa suggests a latest Eocene age of the fossil flora. The plant assemblage is typical of paratropical or subtropical evergreen forests in a warm and humid subtropical climate, recent counterparts of which occur in southeast Asia. The presence of Nypa is characteristic of mangroves. The good state of preservation of the leaves suggests coastline proximity during sedimentation of the plant-bearing deposits.

In the central-eastern Sirt Basin, enigmatic Intisar domal structures host significant hydrocarbon accumulations. These structures have been commonly interpreted as pinnacle reefs/bioherms occurring in the open-marine basinal environment. Generally, pinnacle reefs/bioherms are mainly characterized by in situ carbonates. The current study challenges the Intisar pinnacle reef/bioherm model by examining one of the domal structures in terms of biostratigraphy, microfacies and depositional environment. These structures were dated using larger benthic foraminifera, which yielded a Middle to Late Paleocene age (Selandian–Early Thanetian). Thirteen microfacies types representing different carbonate ramp environments ranging from outer ramp to inner ramp, were defined. Outer ramp deposits have been observed adjacent to the domal structure, represented mainly by wackestone with small benthic and planktonic foraminifera. The outer ramp deposits are most likely isochronous to the domal structures. The lower part of the domal structures is composed mainly of foraminiferal–algal–echinodermal packstones. The upper part is characterized by foraminiferal–algal–echinodermal packstones with intercalated microbialite–coral boundstones. The euphotic inner ramp deposits are preserved on the crest of the domal structure, consisting of grainstone and packstone rich in Glomalveolina. As a result of this study, the Intisar domal structures are seen as erosional relics of a carbonate ramp and no evidence for pinnacle reef/bioherm model was found.

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