Zoeken
Zoeken kan via de modus 'eenvoudig zoeken' (één veld) of uitgebreid via 'geavanceerd zoeken' (meerdere velden). Zo kan je bv. zoeken op een combinatie van een auteursnaam (auteur), een jaartal (jaar) en een documenttype.
Boekenmand
Nuttige resultaten kan je aanvinken en toevoegen aan een mandje. De inhoud hiervan kan je exporteren of afdrukken (naar bv. PDF).
RSS
Op de hoogte blijven van nieuw toegevoegde publicaties binnen uw interessegebied? Dit kan door een RSS-feed (?) te maken van jouw zoekopdracht.
nieuwe zoekopdracht
Benthic foraminifers and gastropods from the Gratteri Formation cropping out near Isnello (Madonie Mts., Sicily)
Benedetti, A.; D'Amico, C. (2012). Benthic foraminifers and gastropods from the Gratteri Formation cropping out near Isnello (Madonie Mts., Sicily). Ital. J. Geosci. 131(1): 66-76. https://dx.doi.org/10.3301/IJG.2011.23
In: Italian Journal of Geosciences. Societa Geologica Italiana: Roma. ISSN 2038-1719; e-ISSN 2038-1727
| |
| Trefwoord |
|
| Author keywords |
Foraminifers, molluscs, biometry, Nephrolepidina, Gratteri Formation, Sicily |
| Auteurs | | Top |
- Benedetti, A.
- D'Amico, C.
|
|
|
| Abstract |
Nine samples were collected from a 3 m thick section of the Gratteri Formation cropping out at Casa Asciutto, near Isnello (Madonie Mts.) consisting of yellow silty marls alternating to bioclastic marly and quartzy sandstones, rich in displaced larger foraminifers such as lepidocyclinids (Nephrolepidina and Eulepidina), and nummulitids (Heterostegina and Operculina). Planktonic foraminifers are badly preserved or absent through the section because of dissolution. The presence of displaced specimens of Nephrolepidina praemarginata, which was the object of a biometrical analysis for the embryonic apparatus, dates the studied section at least late Rupelian. In the silty marl layers deep water agglutinated foraminifers (DWAF) and bathyal hyaline foraminifers are frequent; 36 agglutinated and 26 hyaline species of benthic foraminifers, some of which in open nomenclature, were identified. Upsection the specific diversity tends to decrease, whereas the quartz supply increases and assemblages become exclusively constituted by agglutinated DWAF with predominant tubular suspension feeding taxa. In three samples few, badly preserved and displaced gastropods belonging to Architectonicidae, Ampullinidae, Trochidae, Cerithiopsidae, Rissoidae and Pyramidellidae were recognized. The Gratteri Formation deposited during the late Rupelian in a basin periodically affected by gravitative and turbiditic flows, which carried basinward coeval shallow-water larger foraminifers and gastropods. The dissolution of the most calcareous taxa is imputed to the fluctuations and local rise of the calcite compensation depth (CCD) or, more likely, to reducing conditions in bottom sediments. |
IMIS is ontwikkeld en wordt gehost door het VLIZ.