Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

3 Acta Geologica Polonica

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: amonit

Sortuj według:

Ogranicz wyniki do:

Early Cretaceous ammonites from the Butkov Quarry (Manin Unit, Central Western Carpathians, Slovakia)

100%

Vasicek Z.

tom Vol. 60, no. 3

393-415

The taxonomic and stratigraphic study of rich ammonite material from the Lower Cretaceous deposits of the Butkov Quarry, near Ladce (ManIn Unit, Slovak Central Carpathians) is presented. More than 55 ammonite species are recognised and twenty-one biostratigraphically significant ammonite species are described, with one species, Sarasinella subdensicostata, described as new. The recognised taxa document an interval from the Upper Valanginian through to the Lower Hauterivian. The ammonite assemblage represents the Mediterranean bioprovince, with only a single species, Dichotomites evolutus, from the Boreal bioprovince.a new ammonite zone, the Teschenites flucticulus Zone, is proposed for the basal Hauterivian in the Western Carpathians.

Mosasauroid predation on an ammonite – Pseudaspidoceras – from the Early Turonian of south-eastern Morocco

80%

Gale A. S. , Kennedy W. J. , Martill D.

tom Vol. 67, no. 1

31--46

A juvenile specimen of the ammonite Pseudaspidoceras from the Early Turonian of the Goulmima area in the Province of Er-Rachida in south-eastern Morocco shows clear evidence of predation by a tooth-bearing verte-brate. Most of the body chamber is missing, as a result of post-burial compactional crushing. The adapertural part of the shell on the left flank of the surviving fragment of body chamber bears six circular punctuations; the right flank four. These are interpreted as the product of a single bite by a mosasauroid, probably a Tethysaurus. The taxonomy of the Goulmima Pseudaspidoceras is discuused in an appendix.

The lower and middle Berriasian in Central Tunisia: Integrated ammonite and calpionellid biostratigraphy of the Sidi Kralif Formation

80%

Maalaoui K. , Zargouni F.

tom Vol. 66, no. 1

43--58

The lower and middle Berriasian sedimentary succession of the Sidi Kralif Formation has been a subject of biostratigraphic study in two key sections in Central Tunisia. Our contribution is an attempt to better define the basal Berriasian interval, between the Berriasella jacobi Zone and the Subthurmannia occitanica Zone. Zonal schemes are established using ammonites and calpionellids, and these permit correlation with other regions of Mediterranean Tethys and beyond. The use of biomarkers afforded by microfossil groups has allowed characterization and direct correlation with four widely accepted calpionellid sub-zones, namely Calpionella alpina, Remaniella, Calpionella elliptica and Tintinopsella longa. The two ammonite zones of Berriasella jacobi and of Subthurmannia occitanica are recognised on the basis of their index species. The parallel ammonite and calpionellid zonations are useful as a tool for correlation and calibration in time and space, thus allowing a better definition of a J/K boundary. The presence of four Berriasian calpionellid bioevents is recognised: (1) the ‘explosion’ of Calpionella alpina, (2) the first occurrence of Remaniella, (3) the first occurrence of Calpionella elliptica and (4) the first occurrence of Tintinopsella longa. The last is here documented as coeval with the presence of Subthurmannia occitanica, which marks the lower/middle Berriasian boundary.