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Aptian foraminiferal stratigraphy and Nannoconus assemblages from the Kopka section (Western Tatra Mountains, Poland)

Pszczółkowski A.

Annales Societatis Geologorum Poloniae

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2015

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Vol. 85, No. 1

123--138

EN

In the Kopka section (Dolina Kościeliska valley, Western Tatra Mountains), the upper part of the Kościeliska Marl Formation consists of biomicrites with marly interbeds. These deposits, 76 m thick, are assigned to the Praehedbergella excelsa and Leupoldina cabri zones, of Aptian age. The taxa identified belong mainly to the genera Praehedbergella Gorbachik and Moullade, 1973, Globigerinelloides Cushman and Ten Dam, 1948 (emended by Longoria 1974 and Verga and Premoli Silva, 2003a) and Gorbachikella Banner and Desai, 1988. Nineteen Nannoconus taxa were identified during an SEM study of 34 samples. The occurrence of N. vocontiensis in the higher part of the section allows the nannoconid assemblages in the upper part of the section to be distinguished from those in the lower part. Four Nannoconus assemblages were recognized in these limestones: (1) Nannoconus bucheri-N. steinmannii, (2) N. truitti frequens, (3) N. vocontiensis and (4) N. aff. regularis. The wide-canal Nannoconus specimens are more frequent than the narrow-canal ones in the limestones of earliest Aptian age (Praehedbergella excelsa Zone), but the wide-canal forms predominate consistently in the upper part of the section, still within the L. cabri Zone.

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Upper Albian to Lower Cenomanian biostratigraphy in the Oyubari area, Hokkaido, Japan : toward a Cretaceous biochronology for the North Pacific

Kawabe F.

Acta Geologica Polonica

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2003

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Vol. 53, nr 2

81-91

EN

An integrated planktonic foraminifer and ammonoid biostratigraphy for the Oyubari area, Japan, provides new insights into the late Albian to early Cenomanian biochronology of the North Pacific province. The following foraminifers extend Tethyan zonation to the Oyubari area: Biticinella breggiensis (lower Upper Albian), Rotalipora subticinensis - Rotalipora ticinensis (middle Upper Albian), Rotalipora appenninica (upper Upper Albian), and Rotalipora globotruncanoides (Lower Cenomanian) zones. Co-occuring age-indicative ammonoids such as Mortoniceras rostratum, Mariella bergeri, and Mantelliceras saxbii, are in accord with these foraminifer ages. The base of the Cenomanian stage in Hokkaido is recognized as the first occurrence of Rotalipora globotruncanoides, which is close to the horizon of the occurrence of Mantelliceras. The first occurrence of Desmoceras (Pseudohligella) japonicum, regarded as a Cenomanian marker species in the North Pacific province, is of latest Albian age in the global biochronological scale.

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The Margot Formation in Western Cuba: a Volcanic and Sedimentary Sequence of (Mainly) Cenomanian-Turonian Age

Pszczółkowski A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2002

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Vol. 50, nr 2

193-205

EN

The stratotype of the Margot Formation was previously established at the Mina Margot in the Matanzas Province of western Cuba. The limestone interbeds occurring between the basalts of the upper part of this formation contain Turonian planktonic foraminifers. Late Cretaceous age and tectonic position of the Margot Formation in the Palaeogene thrust nappes exposed in the northwestern Matanzas Province suggest the Caribbean plateau origin of the basalts occurring in this unit. According to an alternative interpretation, the Margot Formation represents a fragment of the section of the proto-Caribbean Oceanic crust, mainly of Cenomanian-Turonian age.

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Crustacean Burrows from Upper Maastrichtian Deposits of South-Central Cuba

Pszczółkowski A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2002

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Vol. 50, nr 2

147-163

EN

In south-central Cuba, the shallow-water limestones of the Late Maastrichtian Cantabria Formation underlie the Late Maastrichtian to Early Eocene Vaqueria Formation. The crustacean burrows (Thalassinoides isp.) occur in Late Maastrichtian marl of the lowermost part of the latter formation. Horizontal tunnels are the most common components of the reported low density burrow system produced in this shelfal deposit. Occurrence of Gansserina gansseri (Bolli), 1951, constrains the age of the burrow-filling biomicrite between 68 (probably 67) and 65.45 Ma. The submergence of the Cantabria shallow-water limestones and sedimentation of the burrow-filling biomicrite coincide with the high sea-level during Late Maastrichtian. The Late Maastrichtian deposits were partly truncated by pre-Palaeocene (K-T boundary?) erosion. However, in comparison with the successions of western Cuba, the Cienfuegos sedimentary basin occupied a more remote position in respect to the Chicxulub impact crater in Yucatan, thought to be the K-T event source.

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New data on Late Albian and Late Cenomanian Nannoconid Assemblages from Cuba

Pszczółkowski A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2000

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Vol. 48, nr 2

135-149

EN

The nannoconid assemblage found in a Late Albian limestone layer of the Santa Teresa Formation in western Cuba contains both the taxa known to occur in the Albian (Nannoconus truitti truitti, N. cf. elongatus and N. cf. regularis), and also those usually not reported from the post-Aptian strata (N steinmannii steinmannii, N. cf. colomii, N. gr. colomii-steinmannii). Planktonic foraminifers occurring in this layer are Late Albian in age. The narrow-canal taxa of the genus Nannoconus Kamptner, 1931, are interpreted as the in situ components of the described Late Albian nannofossil assemblage. Presence of scarce nannoconids, identified as N. truittii truittii, N. regularis and N. cf. regularis, in samples of Late Cenomanian limestones exposed in western and central Cuba, is also recorded.