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Measurements (in mm) and ratios of Paraulacosphinctes transitorius (Oppel, 1865). AS III -Bayerische Staatssammlung in Munich, PL -Nový Jičín Regional Museum.
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The present contribution deals with the taxonomy of seven species of perisphinctoid ammonite from the Štramberk Limestone (Outer Western Carpathians, Czech Republic) deposited in Moravian-Silesian museums. The age of these studied ammonites is compared with that of index microfossils contained in the matrix adhering to or infilling the studied spec...
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... The species comes from the Š tramberk limestones, consisting of base-of-slope conglomerates and slump bodies within the Cretaceous part of the Hradiště Formation (Picha et al., 2006). The age of Aulaconautilus picteti thus also remains unclear, even if a Tithonian-early Berriasian age is convincing according to coeval ammonite faunas (Vašíček and Skupien, 2016;Vašíček et al., 2017;Frau et al., 2016a-b). ...
... Age: Late Jurassic-Early Cretaceous Štramberk is historically famous for its abundance of fossils. The Štramberk Limestone is exposed as carbonate mega blocks, breccias and conglomerates at several quarries (i.e., Kotouč, Municipal, Horní Skalka and Castle Hill) near the town of Štramberk (Vašíček et al., 2017(Vašíček et al., , 2018. The brachiopods in the collections could have been found in the area. ...
The paleontological collection of Georg Gasser gives important insights in the fossiliferous sites of the 19th and 20th century, and the fossils collected and studied during that time interval. With about 90% the invertebrates represent the biggest part of the paleozoological specimens. All major groups are represented, although there is a clear predominance of molluscs reflecting Gasser’s particular predilection for these animals. Although 45% of the finds suffer a lack of information on the labels. The collections give us nonetheless a picture of the main areas of provenance for the fossils and an hint on Gasser’s compositional idea regarding the collection. A close connection between Gasser and the German-speaking areas in Europe as primary source of the specimens is evident, with only rare exotic exceptions represented by some localities in America, Africa or in the Atlantic Ocean. This work is based on a preliminary study, realized with the aim of promoting insights and favor the divulgation of the historical content of this paleontological heritage.
... Age: Late Jurassic-Early Cretaceous Štramberk is historically famous for its fossil richness. The Štramberk Limestone is exposed as carbonate megablocks, breccias and conglomerates at several quarries (i.e., Kotouč, Municipal, Horní Skalka and Castle Hill) near the town of Štramberk (Vašíček et al., 2017(Vašíček et al., , 2018 Although today ammonites are rarely found and specimens are in general not well preserved, during the 19 th century this area yielded good specimens, now deposited in several museums, often with the generic indication "Stramberg" or "Stramberk" (Vašíček et al., 2017(Vašíček et al., , 2018. Collection Georg Gasser: 1 specimen, Ptychophylloceras ptychoicum (PZO 12316) ...
... Age: Late Jurassic-Early Cretaceous Štramberk is historically famous for its fossil richness. The Štramberk Limestone is exposed as carbonate megablocks, breccias and conglomerates at several quarries (i.e., Kotouč, Municipal, Horní Skalka and Castle Hill) near the town of Štramberk (Vašíček et al., 2017(Vašíček et al., , 2018 Although today ammonites are rarely found and specimens are in general not well preserved, during the 19 th century this area yielded good specimens, now deposited in several museums, often with the generic indication "Stramberg" or "Stramberk" (Vašíček et al., 2017(Vašíček et al., , 2018. Collection Georg Gasser: 1 specimen, Ptychophylloceras ptychoicum (PZO 12316) ...
In Gasser’s paleozoological collection, cephalopods account for 12% of all specimens. Ammonoidea, Coleoidea, Orthoceratoidea, Nautiloidea and Bactritoidea are the groups represented. Ammonoidea are best documented, with a good variety of genera and species. A preliminary revision was carried out by a former volunteer at the museum (Helmuth Buratti) some ten years ago. Unfortunately, about 40% of the specimens lack information related to their geographic origin. The largest portion of the cephalopod collection comes from Central Europe with the main areas of origin being Germany and the territories of the former Austro-Hungarian Empire. Historical Fossil-Lagerstätten and famous fossiliferous lithostratigraphic groups like the Muschelkalk and Solnhofen Plattenkalks of the German regions of Baden-Württemberg and Bavaria, are well represented by ammonoids, nautiloids and coleoids. The oldest specimens date back to the Silurian and Devonian and come from the German regions of Sauerland (North-Rhine Westphalia) and Hesse, as well as from Poland or from the classic “Barrandian” area in the Czech Republic. The youngest specimen is from the Early Oligocene at Itzehoe (northern Germany). Interestingly, ammonoids from Northern Italy, and especially Trentino-South Tyrol, are relatively rare in the collection. They seem to be linked rather to chance
findings by local collectors or Georg Gasser himself, than to a systematic collecting activity. The area is represented, e.g., by some Triassic ammonoids from the St. Cassian Formation (Dolomites; Bozen/Bolzano Province).
... Although at the first sight, the ammonite fauna in the Štramberk Limestone facies of the Eastern Getic Carbonate Platform seems to be scarcely occurring, however the case of the Outer Western Carpathians, in Czech Republic, where a rich Berriasian ammonite fauna exist and has been described in the Štramberk Limestone facies (Vašíček & Skupien 2013Vašíček et al. 2017Vašíček et al. , 2018, this should be a stimulus for a more intensive collecting of earliest Cretaceous ammonite faunas, aiming to better constrain the dating of the last stage in the evolution of the Eastern Getic Carbonate Platform. ...
... Although at the first sight, the ammonite fauna in the Štramberk Limestone facies of the Eastern Getic Carbonate Platform seems to be scarcely occurring, however the case of the Outer Western Carpathians, in Czech Republic, where a rich Berriasian ammonite fauna exists and has been described in the Štramberk Limestone facies (Vašíček & Skupien 2013Vašíček et al. 2017Vašíček et al. , 2018, this should be a stimulus for a more intensive collecting of earliest Cretaceous ammonite faunas, aiming to better constrain the dating of the last stage in the evolution of the Eastern Getic Carbonate Platform. ...
The Eastern Getic Carbonate Platform, labelled as the Leaota Carbonate Platform by Patrulius et al.
(1976), is largely extended in the eastern part of South Carpathians. It includes the Upper Jurassiclowermost Cretaceous carbonate succession, generally ascribed to the Štramberk Limestone facies,
from the Piatra Craiului Massif, Dâmbovicioara Couloir, Brașov Mountains, Piatra Mare Massif,
Măgura Codlei and the Bucegi Mountains (Patrulius 1969, Dragastan 2010).
Dating the final stage in the evolution of the Eastern Getic Carbonate Platform represented and still
represents a challenging debate. Based on foraminifera and calcareous algae, the carbonate succession of the Eastern Getic Carbonate Platform is assigned to the Kimmeridgian-lowermost Valanginian stratigraphic interval (e.g. Bucur 1978; Bucur et al. 2011, 2014; Grădinaru et al. 2016;
Mircescu et al. 2014, 2016, 2019).
Among the macrofaunas, the ammonites that apparently seemed to be scarcely occurring received a
little attention and only occasionally have been mentioned and discussed. There were a few findings mentioned in the older literature (Popovici-Hatzeg 1898; Jekelius 1938). Patrulius (1969),
Patrulius et al. (1976) had referred to some of them. Patrulius & Avram (2015) taxonomically revised the two specimens in Popovici Hatzeg’s collection as Berriasella (Picteticeras) cf. picteti
(JACOB) (= B. callisto, in coll. IG P 780), Berriasella (Picteticeras) aff. elmii LE HÉGARAT (= Perisphinctes eudichotomus, in Popovici-Hatzeg’s coll. IG P 10522), and dated them as the lowermost
Berriasian.
As the ammonites are particularly valuable biostratigraphic time indicators and precise tools for
time-correlation of strata, we decided to identify in the collections the ammonite specimens mentioned in the above-mentioned publications, aiming for an accurate taxonomic identification of
them. Besides the two ammonite specimens that have been found by Popovici-Hatzeg in the
Dâmbovicioara area and revised by Patrulius & Avram (2015), in the collections of the Geological
Museum of Romania have been identified the two ammonite specimens found by Popovici-Hatzeg
(1898) in the olistolith from Piatra Arsă, in the Bușteni region on the eastern slope of the Bucegi
Mts. From the same region, there is another historical finding done by Gh. Murgoci (Berriasella, in
coll. IG P 485). Till now, the repository of the ammonites mentioned by Jekelius (1938) is not identified yet.
The results of the taxonomic revisions are as follows:
1/ Berriasella (Berriasella) elmii LE HÉGARAT, 1973 (specimen designated as Berriasella
(Picteticeras) aff. elmii LE HÉGARAT, by Patrulius & Avram, 2015)
2/ Berriasella oxycostata MAZENOT, 1939 (specimen of Murgoci designated as Berriasella, and
specimen designated as Berriasella (Picteticeras) cf. picteti (JACOB) by Patrulius & Avram, 2015).
An ammonite specimen identified as Spiticeras (Spiticeras) kiliani DJANÉLIDZÉ, 1922, which has
been found in the limestone clasts of the Bucegi Conglomerate occurring on the Bucegi Plateau, is
added here to the two above-mentioned berriasellid species.
According to the literature, all specimens occur in the lower Berriasian (Jacobi ammonite Zone)
(e.g. Vašíček & Skupien 2013, 2016; Vašíček et al. 2017, 2018).
It is worth to note that Tintinnopsella carpatica (Murgeanu & Filipescu) has been described from
the limestone bearing the berriassellid specimen found by Murgoci (fide Patrulius 1969, foote note
p.95).
The 12
th
Romanian Symposium of Palaeontology, September 19-21, 2019
39
The ammonite specimen assigned to Berriasella carpathica (Zittel) (coll. IG P 735) is too
fragmentary to be identified, but the dense ribbing and type of coiling suggest a some berriasellid
from the upper Berriasian.
Concluding, by the available ammonite fauna the last stage in the evolution of the Eastern Getic
Carbonate Platform did not overcome the Berriasian, as Patrulius (1976) already stated.
Although at the first sight, the occurrence of the ammonite fauna in the Štramberk facies of the
Eastern Getic Carbonate Platform seems to be scarce, however the case of the Outer Western
Carpathians, in Czech Republic, should be a stimulus for a more intensive collecting of earliest
Cretaceous ammonite faunas, aiming to better dating the last stage in the evolution of the Eastern
Getic Platform.
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... Houša, 1990;Houša and Řehánek, 1993;Houša in Houša and Vašíček, 2004). However, calpionellids and ammonites , 2014, 2016Vašíček et al., 2017Vašíček et al., , 2018) in the limestone bodies are indicative of the entire Tithonian and the lowermost Berriasian. Therefore, the aim of our multidisciplinary research has been to assess the existence of Jurassic-Cretaceous boundary strata at the locality (sensu the concept of the Berriasian Working Group: base of Calpionella Alpina Subzone within the M19n.2n ...
... The Štramberk Limestone provided a rich ammonite association Vašíček et al., , 2017Vašíček et al., , 2018 cf. asper, Riasanella cf. ...
... swistowianus and Proniceras jacobi. All of these ammonites have been figured, by Vašíček andSkupien (2013, 2016), Vašíček et al. (2017Vašíček et al. ( , 2018, resp. Eliáš and Vašíček (1995). ...
A high-resolution multidisciplinary study of two profiles in the Kotouč Quarry at Štramberk was carried out to define the age and palaeoenvironmental setting of the peri-reefal Štramberk Limestone. Calpionellids of the Alpina and Ferasini subzones of the standard Calpionella Zone confirm an early Berriasian age for both studied sequences. The presence of the calcareous nannofossils Nannoconus kamptneri minor and ?Speetonia colligata supports this stratigraphic interpretation. An ammonite assemblage with Pseudosubplanites grandis was found corresponding to the upper part of the lower Berriasian (Grandis Subzone). Foraminiferan assemblages contain several taxa previously reported from the Valanginian. Magnetostratigraphy verifies that the studied sections span the magnetozones M18r to M18n. Rock magnetic measurements indicate magnetite as the carrier of characteristic remanent magnetization. A palaeolatitude suggested location at 36°N. Microfacies indicate palaeoenvironments of slope (FZ 4), platform margin reefs, sand shoals (FZ 5, FZ 6) and possibly patch-reefs in the inner platform (FZ 7). The presence of calpionellids and the polychaete Terebella lapilloides suggests deposition within the deeper parts of the outer ramp of a platform slope, with redeposited clasts derived from nearby reef slopes and/or talus. This research contributes to the Berriasian Working Group's efforts to define the Tithonian–Berriasian boundary.
In part 1 of this work we discussed the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on prevailing practical methods for correlation in that J/K interval, traditional usage and the consensus over the best boundary markers that had developed in the last forty years. This consensus has developed further, based on the results of multidisciplinary studies on numerous sites over the last decade. Here in Part 2 we give an account of the application of those results by the Berriasian Working Group (ISCS), and present the stratigraphic evidence that justifies the selection of the locality of Tré Maroua (Hautes-Alpes, SE France) as the proposed GSSP. We describe a 45 m-thick section in the Calcaires Blancs vocontiens – that part of the formation covering the calpionellid Chitinoidella, Remanei. Intermedia, Colomi, Alpina, Ferasini, Elliptica and Simplex biozones. The stratigraphic data collected here has been compiled as part of a wider comparative study of complementary Vocontian Basin sites (with localities at Charens, St Bertrand, Belvedere and Le Chouet). Evidence from Tré Maroua thus sits in this substantial regional biostratigraphic and magnetostratigraphic con- text. For the purposes of the GSSP definition, here we particularly concentrate on the unbroken sequence and biotic markers in the interval immediately below the boundary, the Colomi Subzone (covering circa 675,000 years), and immediately above, the Alpina Subzone (covering circa 725,000 years). Particularly significant fossil datums identified in the Tré Maroua profile are the primary basal Berriasian marker, the base of the Alpina Subzone (a widespread event marked by dominance of small Calpionella alpina, with rare Crassicollaria parvula and Tintinopsella carpathica): the base of the Berriasian Stage is placed at the base of bed 14, which coincides with the base of the Alpina Subzone. Secondary markers bracketing the base of the Calpionella Zone are the FOs of the calcareous nannofossil species Nannoconus wintereri, close below the boundary, and the FO of Nannoconus steinmannii minor, close above. The Tithonian/Berriasian boundary level occurs within M19n.2n, in common with many documented sites, and is just below the distinctive reversed magnetic subzone M19n.1r (the so-called Brodno reversal). We present data which is congruent with magnetostratigraphic and biostratigraphic data from other key localities in France and in wider regions (Le Chouet, Saint Bertrand, Puerto Escaño, Rio Argos, Bosso, Brodno, Kurovice, Theodosia...), and thus the characteristics and datums identified at Tré Maroua are key for correlation and, in general, they typify the J/K boundary interval in Tethys and connected seas.
STATUS OF THIS PROPOSAL: After more than ten years of work the Berriasian WG completed its discussions and arrived at what was considered to be the best possible proposal for the Berriasian GSSP. The work has demanded important effort, time and financial input from the WG members, with considerable diversion from their everyday aims, functions and duties. The informed specialists of the WG overwhelmingly voted, firstly to choose a primary marker (by 75%) and then to choose a GSSP (by 73%). These decisions were based on sound correlations, founded on documentation of many sites and their fossil, magnetic and other characters. The derived data for the GSSP compares well and in some cases are even superior to those used to define other ratified Cretaceous GSSP's. The approved proposal was first submitted to the Cretaceous Subcommission on 1st December 2019, and during the following six weeks the WG received some negative comments produced by three members of the Subcommission. On that basis the proposal was reviewed and most observations and criticisms were answered with a direct written reply and/or by inserting explanations and improvements into the original text. Regrettably, the WG never got back any comment on its detailed revision. The revised proposal covered all the limitations and positives for correlation in the J/K interval and all that is correlatively possible and useful was described, and what is less possible was discussed, even at some length. Its conclusions have already been cited (Gradstein et al., 2020). Finally, in September 2020 the reviewed proposal was resubmitted and was the subject of a vote by the Cretaceous Subcommission. Of the twenty-two persons in the Subcommission, eight (32%) voted against the proposal, eight voted “Yes”, four did not vote, and two abstained. When the Subcommission Chairperson was asked for the concrete reasons that justified the negative votes the only reply was that “the voting members of the Subcommission are free to express their opinions and provide explanations if they are willing to do so”. Clearly, an unexpected answer within a scientific organization like ICS/IUGS. Although, as here explained, this proposal has not been approved and its final status remains open, the authors continue with research on the site and with publication of Part 2, as it contains a wealth of information that could be useful for future research.
GRADSTEIN F.M., OGG J.G., SCHMITZ M.D., OGG G.M. (Eds.), 2020 – Geologic time scale. Elsevier.
Abstract. In part 1 of this work we discussed the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on prevailing practical methods for correlation in that J/K interval, traditional usage and the consensus over the best boundary markers that had developed in the last forty years. This consensus has developed further, based on the results of multidisciplinary studies on numerous sites over the last decade. Here in Part 2 we give an account of the application of those results by the Berriasian Working Group (ISCS), and present the stratigraphic evidence that justifies the selection of the locality of Tré Maroua (Hautes-Alpes, SE France) as the proposed GSSP. We describe a 45 m-thick section in the Calcaires Blancs vocontiens – that part of the formation covering the calpionellid Chitinoidella, Remanei. Intermedia, Colomi, Alpina, Ferasini, Elliptica and Simplex biozones. The stratigraphic data collected here has been compiled as part of a wider comparative study of complementary Vocontian Basin sites (with localities at Charens, St Bertrand, Belvedere and Le Chouet). Evidence from Tré Maroua thus sits in this substantial regional biostratigraphic and magnetostratigraphic context. For the purposes of the GSSP definition, here we particularly concentrate on the unbroken sequence and biotic markers in the interval immediately below the boundary, the Colomi Subzone (covering circa 675,000 years), and immediately above, the Alpina Subzone (covering circa 725,000 years). Particularly significant fossil datums identified in the Tré Maroua profile are the primary basal Berriasian marker, the base of the Alpina Subzone (a widespread event marked by dominance of small Calpionella alpina, with rare Crassicollaria parvula and Tintinopsella carpathica): the base of the Berriasian Stage is placed at the base of bed 14, which coincides with the base of the Alpina Subzone. Secondary markers bracketing the base of the Calpionella Zone are the FOs of the calcareous nannofossil species Nannoconus wintereri, close below the boundary, and the FO of Nannoconus steinmannii minor, close above. The Tithonian/Berriasian bound-ary level occurs within M19n.2n, in common with many documented sites, and is just below the distinctive reversed magnetic subzone M19n.1r (the so-called Brodno reversal). We present data which is congruent with magnetostratigraphic and biostratigraphic data from other key localities in France and in wider regions (Le Chouet, Saint Bertrand, Puerto Escaño, Rio Argos, Bosso, Brodno, Kurovice, Theo-dosia...), and thus the characteristics and datums identified at Tré Maroua are key for correlation and, in general, they typify the J/K boundary interval in Tethys and connected seas.
Here in the first part of this publication we discuss the possibilities for the selection of a GSSP for the Berriasian Stage of the Cretaceous System, based on the established methods for correlation in the Tithonian/Berriasian interval. This will be followed, in the second part, by an account of the stratigraphic evidence that justifies the locality of Tré Maroua (Hautes-Alpes, SE France) as the proposed GSSP. Here we discuss the possibilities for correlation in the historical J/K boundary interval, and the evolution of thinking on the positioning of the boundary over recent generations, and in relation to research in the last ten years. The Tithonian/Berriasian boundary level is accepted as occurring within magnetosubzone M19n.2n. The detailed distribution of calpionellids has been recorded at numerous sites, tied to magnetostratigraphy, and the base of the calpionellid Alpina Zone is taken to define the base of the Berriasian Stage. This is at a level just below the distinctive reversed magnetic subzone M19n.1r (the so-called Brodno reversal). We discuss a wide range of magnetostratigraphic and biostratigraphic data from key localities globally, in the type Berriasian areas of France and wider regions (Le Chouet, Saint Bertrand, Puerto Escaño, Rio Argos, Bosso, Brodno, Kurovice, Theodosia etc.). The characteristic datums that typify the J/K boundary interval in Tethys and its extensions are detailed, and the correlative viability of various fossil groups is discussed. The boundary level is correlated to well-known J/K sections globally, and a series of secondary markers and proxies are indicated which assist wider correlation. Particularly significant are the primary basal Berriasian marker, the base of the Alpina Subzone (marked by dominance of small Calpionella alpina, Crassicollaria parvula and Tintinopsella carpathica) and secondary markers bracketing the base of the Calpionella Zone, notably the FOs of the calcareous nannofossil species Nannoconus wintereri (just below the boundary) and the FO of Nannoconus steinmannii minor (just above). Notable proxies for the boundary are: 1) the base of the Arctoteuthis tehamaensis Zone in boreal and subboreal regions, 2) the dated base of the Alpina Subzone at 140.22 ± 0.14 Ma, which also gives a precise age estimate for the system boundary; and 3) the base of radiolarian “unitary zone” 14, which is situated just above the base of the Alpina Subzone.
A bed-by-bed biostratigraphical study of two key Californian outcrop sections of the Jurassic–Cretaceous transition interval is presented. The studied succession is characterized by the occurrence of abundant buchiid bivalves and a discontinuous ammonite record. Several Lower Cretaceous ammonite zones were introduced in the literature, but the precise stratigraphic position of key ammonite records remains unclear. Consequently, the buchiid zonation established in the 1970s is still considered the prime biostratigraphic tool, and ammonites have supplementary value. The buchiid zonation is revised herein, and the nomenclature and boundaries are updated. The Buchia sublaevis zone (upper Valanginian (?) to lower Hauterivian) is for the first time recognised in California. Two further biostratigraphic units, i.e. ‘Buchia inflata beds’ (between B. uncitoides and B. pacifica zones) at McCarty Creek and ‘Buchia aff. volgensis-B. unschensis beds’ (between B. piochii and B. okensis zones) at Grindstone Creek, are proposed. The positions of zonal boundaries are determined more precisely than previously, and are based on the first or mass occurrence of index species. As a result, the Panboreal correlation of Tithonian to Hauterivian buchiid zones is improved. Ammonite biohorizons are used as an additional correlative tool, and the following succession is proposed for the Upper Tithonian to earliest Hauterivian interval of the study area: Fierrites dilleri, Paradontoceras storssi, Proniceras maupinense, Neocosmoceras euchrense, Paskentites paskentaensis, Kilianella crassiplicata, Neotollia mutabilis, Sarasinella hyatti, Thurmanniceras stippi, T. jenkinsi and Jeannoticeras jeannoti. A new genus, Howarthiceras n. gen. is established for “Groebericeras” baylei Imlay and Jones.
