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1

The Belemnitella stratigraphy of the Upper Campanian : basal Maastrichtian of the Middle Vistula section, central Poland

Remin Z.

Geological Quarterly

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2015

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Vol. 59, No. 4

783--813

EN

This taxonomy and stratigraphy of the Upper Campanian and Lower Maastrichtian Belemnitella lineages, from the Middle Vistula sections, based on new collections, is presented. The correlation to the basal Maastrichtian standard GSSP at Tercis, France, is provided based on inoceramid bivalve stratigraphy. The Artificial Neural Networks (ANN), particularly the self-organizing Kohonen algorithm, was applied to taxonomic discrimination. Eight morphotypes within the genus Belemnitella, understood here as natural species populations, were recognised. Five of these are assigned to known taxa: Belemnitella mucronata, B. posterior, B. minor [= B. minor I and B. minor II], B. langei and B. najdini; and three, B. sp. a, B. sp. 1 and B. sp. 2, are left in open nomenclature. Four Belemnitella zones are proposed. Due to its palaeogeographic position, between Western and Eastern Europe, the Middle Vistula section is characterized by the co-occurrence of Belemnitella species from those two areas. Consequently, it enables better correlation of Belemnitella-based schemes; the East European B. najdini and B. posterior are placed next to West European B. minor chronospecies I and II. The Campanian/Maastrichtian boundary, as currently defined, is placed at the top of the najdini – posterior Zone, which is an equivalent of the Belemnella-based boundary, i.e. at the base of the Belemnella obtusa / Belemnella vistulensis zones. Within the top of the najdini – posterior Zone occurs a level (an interval of only a few metres), where nearly all of the Upper Campanian Belemnitella disappear. This level coincides with taxonomic changes observed within the co-occurring representatives of genus Belemnella.

2

Life span and growth rate of Middle Jurassic mesohibolitid belemnites deduced from rostrum microincrements

Wierzbowski H.

Volumina Jurassica

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2013

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Vol. 11, no. 1

1--18

EN

The microincrements of nine Middle Jurassic mesohibolitid belemnite rostra (Hibolithes jurensis, Pachybelemnopsis fusiformis and Pachybelemnopsis “subhastatus”) were analysed to measure the ontogenic age and growth rate of the belemnites. The microincrements are interpreted to have been formed daily based on analogy with extant coleoid cephalopods and the frequency of circadian rhythms in animal activity. The mesohibolitid belemnites are found to have had a short life span of ca. 1 year. The short life span of the belemnites studied is similar to the life span of modern coleoids (squids, cuttlefishes and common octopuses). It restricts the utility of belemnite rostra as a proxy for average secular seawater temperatures and chemistry. Short-lived cycles (2–8 days) in the belemnite growth rate are linked to variations in the metabolic activity of these animals. Minor diagenetic alteration revealed by the dull cathodoluminescence of some rostra is found to have no effect on the preservation of the growth rings.

3

The Belemnella stratigraphy of the Campanian-Maastrichtian boundary; a new methodological and taxonomic approach

Remin Z.

Acta Geologica Polonica

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2012

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Vol. 62, no. 4

495-533

EN

The taxonomy and stratigraphy of the Upper Campanian and Lower Maastrichtian belemnites from the Vistula (central Poland) and Kronsmoor (northern Germany) sections are revised on the basis of new collections from the Vistula section as well as a reinvestigation of the classic collection of Schulz from the Kronsmoor section. For the taxonomic description a new biometric procedure is proposed, which can be applied to both the genera Belemnella and Belemnitella. For the species-level taxa recognition the Artificial Neural Networks method, the self-organizing Kohonen algorithm, was implemented. This new taxonomic and methodological approach enabled the recognition of nine species of the genus Belemnella. Five of them can be assigned to the existing species B. lanceolata, B. longissima, B. inflata, B. obtusa and B. vistulensis. However, the species concept differs from that applied by Schulz (1979). As a consequence, the stratigraphic ranges of these species are modified. Four species are left in open nomenclature and represent possibly new species. Future studies may reveal that they might be assigned to East European forms from Ukraine or Russia. The species of Belemnella recognized are placed into the stratigraphic framework based on the standard ammonite and inoceramid bivalve zonations, especially those recognized in the Vistula section. The newly proposed belemnite zonation for the Vistula and Kronsmoor sections is correlated via inoceramids with the standard GSSP at Tercis, France, in order to identify the base of the Maastrichtian Stage. The Campanian/Maastrichtian boundary as defined in Tercis is placed here at the base of the newly defined B. obtusa and B. vistulensis Zones ["obtusa/vistulensis"] - thus it is markedly higher than the traditional boundary based on the FAD of representatives of the genus Belemnella - This new boundary coincides well with a distinct turnover of belemnite guard morphology and represents one of the most important points in the early evolutionary history of Belemnella. Three belemnite zones defined by their lower boundaries are recognized in the Campanian/Maastrichtian interval, in addition to three subzones recognized within the B. obtusa Superzone. The B. lanceolata and B. inflata zones as understood here are referred to the Upper Campanian [Tercis definition]. The B. obtusa Zone is subdivided into three subzones, viz.: Belemenlla vistulensis, Belemnella sp. G and Belemnella sp. F, which are referred to the Lower Maastrichtian [Tercis definition]. The fast evolving species of Belemnella enable the proposal of a biostratigraphic scheme with a resolution that is higher than those based on inoceramid bivalves and ammonites - the longevity of a belemnite zone could be as low as 200Ky.

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Integrated biostratigraphy of Upper Maastrichtian chalk at Chełm (SE Poland)

Dubicka Z., Peryt D.

Annales Societatis Geologorum Poloniae

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2011

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Vol. 81, No 2

185-197

EN

A 40-m-thick section of chalk exposed in the Chełm quarry (SE Poland) contains a rather poor assemblage of macrofauna and a well diversified assemblage of foraminifers. The planktonic foraminifer assem- blages characterized by a considerable number of representatives of Globigerinelloides and Heterohelix and the presence of Guembelitria cretacea indicate the lowest part of the Guembelitria cretacea Zone sensu Peryt (1980). Benthic foraminifers point out that the strata of the Chełm quarry section can be attributed to the lower part of the Upper Maastrichtian: i.e., the Gavelinella danica/Brotzenella preacuta Zone of the European Boreal Province or the Anomalinoides pinguis Zone distinguished in Poland (except the Carpathians). The occurrence of ammonites, such as Hoploscaphites constrictus lviviensis Machalski, Hoploscaphites schmidi (Birkelund), and Acanthoscaphites varians blaszkiewiczi Jagt & al. indicates that the Chełm succession belongs to the lower part of the Belemnitella junior Zone, i.e., to the Belemnitella junior–Spyridoceramus tegulatus Zone sensu Schulz & Schmid (1983). The correlation of the Chełm quarry section and the Middle Vistula River Valley section indicates that the equivalent interval of the former section is not exposed in the Middle Vistula River Valley and that it would occur between the Chotcza and Lucimia villages within the lower part of the Belemnitella junior Zone, i.e., within the Belemnitella junior-Spyridoceramus tegulatus Zone distinguished in NW Germany (Schulz & Schmid,1983).

5

Integrated stratigraphy of the Kronsmoor section (northern Germany), a reference point for the base of the Maastrichtian in the Boreal Realm

Niebuhr B., Hampton M., Gallagher L., Remin Z.

Acta Geologica Polonica

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2011

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Vol. 61, no. 2

193-214

EN

Results of detailed multistratigraphic analyses of the Campanian.Maastrichtian boundary section at Kronsmoor in northern Germany are summarised and calibrated with the GSSP at Tercis les Bains, southwest France. Additional markers for the definition of the boundary in the Boreal Realm are proposed, and a detailed carbon isotope curve around the Campanian.Maastrichtian boundary in the chalk facies of the Boreal epicontinental sea is presented. The C isotopic GSSP marker for global correlation is the markedly abrupt decrease of c. 0.7 [per mil] [delta^13]C directly at the Campanian.Maastrichtian boundary as dated by ammonites. In electronic borehole measurements the Kronsmoor section covers the SP peaks 53 to 64 and the base of the Maastrichtian being situated just below SP peak 60. The first occurrence (FO) of the ammonite Pachydiscus neubergicus, which corresponds to biohorizon 1 at Tercis, falls in the upper part of nannofossil Zone UC15, at both localities. Biohorizon 3 is the FO of the ammonite Diplomoceras cylindraceum, which first appears in the Upper Campanian of Tercis and at Kronsmoor enters significantly above the FO of Belemnella lanceolata, the conventional Boreal belemnite marker for the base of the Maastrichtian Stage. Based on ammonite evidence, the internationally accepted base of the Maastrichtian at Kronsmoor is located between the FOs of Diplomoceras cylindraceum (Upper Campanian) and Pachydiscus neubergicus (Lower Maastrichtian) c. 11 m above flint layer F 600, at which the first representatives of the belemnite genus Belemnella, in particular Bn. lanceolata occur. The latter thus is a Late Campanian species, appearing c. 450 ky prior to the ammonite-based boundary. The FOs of Belemnella pseudobtusa (sensu Schulz) resp. Belemnella obtusa (sensu Remin) directly at the boundary can be use as the coleoid proxy for the definition of the base of the Maastrichtian in the Boreal Realm. To define the boundary by benthic foraminifera the last occurrence (LO) of Neoflabellina praereticulata is suitable. Biohorizon 12, as defined at Tercis, involves the nannofossil Uniplanarius trifidus, however, at Kronsmoor this species is rare, occurs only sporadically and also significantly lower in comparison to Tercis. It is possible though to compare and correlate nannofossil events between Kronsmoor and Tercis using cosmopolitan taxa such as Broinsonia parca constricta and Eiffellithus eximius. The LO of the latter appears to be situated just above the boundary in both sections; it follows from this that the top of nannofossil Zone UC15 is of Early Maastrichtian age.

6

New stratigraphic and isotope data on the Kimmeridgian-Volgian boundarybeds of the Subpolar Urals, Western Siberia

Rogov M. A., Price G. D.

Geological Quarterly

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2010

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Vol. 54, No 1

33-40

EN

A review and new data regarding the ammonite faunas and biostratigraphy of the uppermost Kimmeridgian-lowermost Volgian of theSubpolar Urals are presented. The combined ranges of almost all ammonite genera in the lowermost Volgian of the Subpolar Urals supports the traditional point of view regarding the equivalence of the Magnum Zone with the two lowermost Bolonian Zones and with thebulk of the Klimovi Zone. This stratigraphic interpretation permits the stable isotope data (carbon and oxygen) derived from associatedbelemnites to be presented in context. The isotopic records from the belemnites suggest that the lower Volgian sediments of the YatriaRiver, Subpolar Ural Mountains were deposited in a warm marine environment consistent with a warm high latitude scenario. If reducedsalinites are invoked apparent temperatures are lowered by ~5°C, but still remain well above freezing and are relatively warm comparedto some recent modelled estimates of Late Jurassic ocean temperatures.

7

Sztuczne sieci neuronowe Kohonena jako narzędzie w taksonomii paleontologicznej - metodyka oraz zastosowanie na przykładzie późnokredowych belemnitów

Remin Z.

Przegląd Geologiczny

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2008

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Vol. 56, nr 1

58-66

EN

Artificial neural networks (ANNs), the computer software or systems that are able to "learn" on the basis of previously collected input data sets are proposed here as a new useful tool in paleontological modeling. Initially ANNs were designed to imitate the structure and function of natural neural systems such as the human brain. They are commonly used in many natural researches such as physics, geophysics, chemistry, biology, applied ecology etc. Special emphasis is put on the Kohonen self-organizing mapping algorithm, used in unsupervised networks for ordination purposes. The application of ANNs for paleontology is exemplified by study of Late Cretaceous belemnites. The Kohonen networks objectively subdivided the belemnite material] ~ 750 specimens) into consistent groups that could be treated as monospecific. The possibility of transferring these results to the language of classical statistics is also presented. Further development and possibility of use of ANNs in various areas of paleontology, paleobiology and paleoecology is briefly discussed.

8

The carbon and oxygen isotope records of Upper Bajocian-Bathonian calcareous fossils from the Polish Jura Chain

Wierzbowski H., Joachimski M.

Volumina Jurassica

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2006

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Vol. 4, no. 1

220-222

EN

A collection of stratigraphically well-dated calcitic and aragonitic fossils (belemnites, ammonites, nautiloids and oysters), derived from Upper Bajocian - Upper Bathonian clays from the Polish Jura Chain (central Poland), were studied for oxygen and carbon isotopes. The preservation state of the shell material was investigated by means of cathodoluminescence microscopy, trace element geochemistry and X-ray diffraction. Palaeotemperatures calculated from the oxygen isotope composition of calcitic shells (belemnites and oysters) are similar to each other despite the significant spread in 18O values (Fig. 1). The 18O values of calcitic fossils generally vary from -0.1 to +1.1‰ VPDB for the studied interval, which corresponds to palaeotemperatures between +7.9 and +12.4°C (calculated with the equation of Anderson & Arthur 1983). The palaeotemperatures derived from the oxygen isotope composition of aragonitic ammonoid and nautiloid shells are distinctly higher (Fig. 1) with most of the estimates ranging from 15 to 23°C (calculated with the equation of Grossman & Ku 1986). The observed temperature difference may have resulted from different depth habitats of the organisms. The ammonites and nautiloids might have lived in surface waters and the temperature contrast might represent a palaeotemperature gradient between thermally stratified surface and deep waters of the Late Bajocian - Late Bathonian sea in the Polish Jura Chain. The ?13C values for the Upper Bajocian - Upper Bathonian belemnite rostra do not indicate major secular variations (Fig. 1). However, the data show a significant scatter of about 1.5‰. Several oyster shells show considerable higher 13C values (around +3‰ VPDB) compared to coeval belemnite rostra (between 0 and +1.5‰ VPDB). This may point to a metabolic fractionation effect that resulted in disequilibrium fractionation of carbon isotopes within belemnite skeletons (cf. Wierzbowski 2002). The aragonitic ammonite and nautiloid shells show a significant variation in 13C with values ranging from -3.7 to +2.2‰ VPDB. The carbon isotope composition of the oysters and the belemnites may suggest that the ?13C value of ancient seawater bicarbonate (HCO3-) averaged +3‰ VPDB.

9

Strontium isotope variations in Oxfordian seawater

Wierzbowski H., Zieliński G.

Volumina Jurassica

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2006

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Vol. 4, no. 1

222-223

EN

The Jurassic strontium isotope curve is characterized by a broad and deep minimum at the Callovian/Oxfordian boundary. However, there are some discrepancies among its datings and the 87Sr/86Sr values represented in various papers (cf. Jones et al. 1994; Podlaha et al. 1999). We analysed well-stratigraphically dated and well-preserved (Fe <150 ppm, Mn <50 ppm) belemnite rostra derived from the Submediterranean and Boreal Provinces (Polish Jura Chain, Swabian Alb, Isle of Skye). Rostra were carefully separated from surrounding sediment with microdrill, ground and dissolved in 2M acetic acid. After removal of insoluble residue, the leachates were evaporated with an admixture of concentrated nitric acid. Strontium separation was performed at two steps: with 100% nitric acid and cation exchange resin (Bio-Rad 50W-X8 with 2.5 M HCl as eluent). Total blank of chemical procedures has been determined to be less than 1 ng of total Sr. The blank value was not enough to affect the Sr isotope ratio at the average sample weight (50 mg). Analyses of strontium isotopic ratio (87Sr/86Sr value) were performed by a VG Sector 54 mass spectrometer (equipped with 7 faraday collectors) at the Institute of Geological Sciences PAS in Warsaw. All isotope ratios were instrumentally corrected for fractionation effect by using the 87Sr/86Sr value of 0.1194 and normalized with NIST 987 isotopic standard (87Sr/86Sr ratio = 0.710248). The scarcity of the data and the spread of results do not allow the exact recognition of the 87Sr/86Sr values in the lowermost Oxfordian (Fig. 1). However, the strontium isotope curve is characterized by a discernible minimum (87Sr/86Sr ratios between 0.70679 and 0.70681) in the uppermost Lower and the Middle Oxfordian. The 87Sr/86Sr ratio rapidly increases starting from the Middle/Upper Oxfordian boundary and reaches about 0.70685 in the uppermost Oxfordian (Bimmamatum and Planula zones). The 87Sr/86Sr ratio of Callovian-Oxfordian seawater, which was the lowest in the Mesozoic, might have been linked to enhanced hydrothermal activity of the seafloor. Nevertheless, the long time-span of this minimum is unusual. The Callovian-Oxfordian 87Sr/86Sr ratio minimum may also be correlated with a crisis in carbonate sedimentation. In addition, the increase of seawater 87Sr/86Sr ratio coincides with a new period of acceleration of carbonate sedimentation in the oceans. The present data may be used to obtain a best fit of the strontium isotope curve in the Oxfordian.

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A Callovian-Kimmeridgian stable isotope record from Staffin Bay, Isle of Skye, UK: implications for the ocean-atmosphere system

Nunn E., Price G., Hart M., Page K., Leng M.

Volumina Jurassica

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2006

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Vol. 4, no. 1

198-198

EN

The Staffin Bay section in the Isle of Skye, UK is one of the most stratigraphically complete Oxfordian sections in Europe. This contribution presents the first high-resolution stable isotope record of this Middle Callovian to Early Kimmeridgian succession. The isotope record includes both terrestrial and marine data that were obtained from microscopic wood debris and belemnites respectively. The organic carbon-isotope record was derived from organic rich sediment samples taken almost entirely from the Staffin Shale Formation. This formation is largely represented by a series of isolated foreshore exposures dominated by mudrocks that were deposited in a predominantly offshore marine environment. Over 200 sediment samples were analysed from the 150 m section. The concurrent ä13C marine carbonate curve was produced using belemnites collected from the same formation. Approximately 200 belemnite horizons were sampled. The organic carbon-isotope data show a broad Lower to Middle Oxfordian positive carbon isotope excursion from the Mariae to Tenuiserratum Zone, with maximum values occurring in the Cordatum Zone. This is followed by a return to pre-excursion values continuing into the Early Kimmeridgian Cymodoce Zone. A brief negative excursion (of ~2‰) is also identified near the Densiplicatum-Tenuiserratum zones boundary. Rock-eval analysis confirms that the organic matter is predominantly terrestrial in origin. The concurrent ä13C marine carbonate curve derived from belemnites shows a broadly similar trend. This suggests that the positive carbon-isotope excursion recorded here may have affected the global carbon reservoir (i.e. the whole ocean-atmosphere system). The carbon-isotope record derived from this section appears to be generally consistent with Oxfordian Tethyan records (e.g. Wierzbowski 2002, 2004) and a preliminary study of the Staffin Bay area by Pearce et al. (2005).

11

First nearly complete skeleton of the Cretaceous duvaliid belemnite Conobelus

Lukeneder A.

Acta Geologica Polonica

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2005

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Vol. 55, no. 2

147-162

EN

The first Cretaceous belemnite preserved with the rostrum, slightly compressed phragmocone and part of the proostracum is described from the Early Cretaceous (Late Valanginian) Rossfeld Formation (Eibeck, Reichraming Nappe of the Northern Calcareous Alps). The rostrum has dorsal groove (alveolar furrow) typical of duvaliids, and its conical shape (round in transverse section outline), and the rounded apex allow its attribution to Conobelus Stolley, 1919. The new species C. pseudoheres sp. nov. is proposed based on the unique features of the specimen, i.e. persistently parallel lateral sides throughout the rostrum and the conical, blunt outline at the apex. The ration between rostrum and phragmocone is 0.78; the distances between the calcitic septa of the anterior end of the phragmocone range from 3 to 5 mm. The proostracum is 0.02 mm thick. The apical angle is 32° and the alveolar angle (posterior end of the phragmocone) is 24°.The alveolus is 40 mm long, yielding a ratio between rostrum and alveolus of 1.86. The depositional history with its fast sedimentation along with absent/limited post-mortem transportation led to extraordinarily good preservation of the examined specimen.

12

Correlation of the Barremian belemnite successions of northwest Europe and the Ulyanovsk - Saratov area (Russian Platform)

Baraboshkin E. J., Mutterlose J.

Acta Geologica Polonica

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2004

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Vol. 54, no. 4

499-510

EN

The marine sedimentary successions of Barremian age yield, both in northwest Europe and on the Russian Platform, diverse and abundant belemnite faunas. These include the genera Praeoxyteuthis, Aulacoteuthis and Oxyteuthis and are attributed to the boreal belemnite family Oxyteuthididae. The Oxyteuthididae are endemic to northwest Europe (northern Germany, northeast England, North Sea) and the Russian Platform, where they evolved in isolation. They possibly derived from the belemnite genus Acroteuthis in Late Hauterivian time. Phylogenetically they are interpreted as the latest off shoot of the Belemnitina, which became extinct in the Early Aptian. Since ammonites are extremely rare on the Russian Platform oxyteuthid belemnites have been used to establish a biozonation scheme with seven belemnite zones (from bottom to top):Praeoxyteuthis hibolitiformis Zone (Early Barremian), Praeoxyteuthis jasikofiana Zone (Early Barremian), Praeoxyteuthis pugio Zone (earliest Barremian), Aulacoteuth is descendens Zone (late Early Barremian), Oxyteuthis brunsvicensis Zone (early Late Barremian), Oxyteuthis germanica Zone (Late Barremian), and Oxyteuthis lahuseni Zone (latest Barremian/Aptian). Apart from the O. lahuseni Zone this zonation can be correlated to the well established belemnite scheme of northwest Europe, allowing a detailed correlation of the Barremian of both areas.

13

Belemnites of the Bohemian Cretaceous Basin in a global context

Kostak M.

Acta Geologica Polonica

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2004

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Vol. 54, no. 4

511-534

EN

Belemnites occur infrequently from the Upper Cenomanian through the Middle/Upper Coniacian in the Bohemian Cretaceous. Four species of the family Belemnitellidae PAVLOW, 1914 have been described so far. A typical boreal faunal incursion, represented by belemnites, happened five to six times in the Bohemian Cretaceous Basin (BCB). Praeactinocamax plenus immigrated during the Late Cenomanian Metoicoceras geslinianum ammonite Zone (plenus Event); there were two short-term incursions of P. bohemicus in the Late Turonian (Subprionocyclus neptuni to Prionocyclus germari ammonite zones) and an incursion of Goniocamax lundgreni in the late Early Coniacian (below and intra-Cremnoceramus crassus inoceramid Zone). A single belemnite fragment was recorded from the "Chlomek Beds"; Middle to Upper Coniacian.Bohemian Cretaceous belemnite systematics, palaeobiogeography (including palaeobiogeographic maps reconstructed), palaeoecology (including the relationship to other coleoid groups . i. e. teuthids) and stratigraphy are discussed.

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The Upper Cretaceous succession (Cenomanian - Santonian) of the Staffhorst Shaft, Lower Saxony, northern Germany: integrated biostratigraphic, lithostratigraphic and downhole geophysical log data

Niebuhr B.

Acta Geologica Polonica

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1999

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Vol. 49, no. 3

175-213

EN

The Cenomanian to Santonian succession of the Staffhorst shaft, ca. 50 km south of Bremen, because of its structural position in the northern German Upper Cretaceous basin, is intermediate in character and fossil content between the pelagic sediments characterizing the Pompeckj Block in the north and the proximal sediments of the Lower Saxony Block in the south. The biostratigraphic subdivision of the shaft is based on inoceramids, echinoids, belemnites and foraminifera. The various biozonations and zonal boundaries used in the Boreal Realm are compared and applied to the zonation of the shaft succession, and the biostratigraphy of the individual fossil groups is described. A new inoceramid zone, that of Inoceramus gibbosus, is proposed for the topmost Lower Coniacian; and an echinoid assemblage zonation is introduced. The existing benthic foraminiferal zonation of the Middle Turonian to Santonian has been modified, with changed age assignments based on the macrofossil zonation. The proposed basal stage boundary criteria of the "Second International Symposium on Cretaceous Stage Boundaries" (Brussels, 1995) could be applied only in some cases. The proximity of the Staffhorst shaft to the trial borehole, situated only 39 m away, has permitted the Self Potential (SP) and Resistivity (R) logs to be uniquely directly calibrated against the lithostraligraphical and biostratigraphic succession of the shaft. The previous identification of some stage and substage boundaries on the logs of northern German boreholes based on foraminiferal zonation will need to be shifted by several tens of metres as a result of thid calibration.