scholarly journals Burdigalian-Langhian foraminifera of the northwest High Zagros Thrust Belt, southwest Iran

Geologos ◽  
2021 ◽  
Vol 27 (2) ◽  
pp. 115-126
Author(s):  
Asghar Roozpeykar ◽  
Iraj Maghfouri Moghaddam ◽  
Mehdi Yaazdi ◽  
Bijan Yousefi
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
Thrust Belt ◽  
Larger Foraminifera ◽  
Southwest Iran ◽  
First Time

Abstract The foraminiferal contents of the lower–middle Miocene succession exposed in three sections in north Nur Abad on the northwestern side of the High Zagros Thrust Belt were studied. Assemblages of larger foraminifera from these sections can be referred to Zone SBZ 25 (and the Miogypsina globulus and Miogypsina intermedia subzones), which correlates with the Burdigalian Stage. For the first time, planktonic foraminifera documented from the Nur Abad area document Lang-hian deposits in the High Zagros, the upper 20 metres of the upper Sayl Cheshmeh section being characterised by the occurrence of planktonic foraminifera such as Globigerina concinna (Reuss), Globigerina diplostoma (Reuss), Globigerinoides obliquus (Bolli), Orbulina bilobata (d’Orbigny) and O.universa (d’Orbigny). This association characterises the Orbulina suturalis Interval Zone.

scholarly journals <i>Bolboforma</i> (Phytoplankton Incertae Sedis), <i>Bachmayerella</i> and other Calciodinelloidea (Phytoplankton) from the Middle Miocene of the Alpine–Carpathian Foredeep (Central Paratethys)

2004 ◽  
Vol 23 (2) ◽  
pp. 139-152 ◽  
Author(s):  
Silvia Spezzaferri ◽  
Fred Rögl
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
High Latitudes ◽  
Calcareous Nannofossils ◽  
Geological Time ◽  
Incertae Sedis ◽  
Sedimentary Sequences ◽  
Unicellular Organisms ◽  
First Time

Abstract. Bolboforma is a microfossil of uncertain origin with affinities to protophytic algae. It generally occurs at high latitudes and/or in cool and temperate waters and has a high stratigraphic potential especially for the Miocene. Calcareous cysts of dinoflagellates represent the ‘benthic cyst stage’ of unicellular organisms belonging to the marine phytoplankton.The occurrence of Bolboforma, Bachmayerella is documented here and, for the first time, some calcareous cysts of dinoflagellates tentatively attributed to Alasphaera and Pithonella from Badenian (Langhian–Middle Miocene) sediments in Austrian and Moravian localities. Alasphaera and Pithonella were previously described from Cretaceous and Danian sediments only, therefore, their range has been extended into the Paratethyan Middle Miocene.Correlation of Bolboforma bioevents with standard geological time-scales allows confirmation, and in some cases refinement, of age assignments based on other microfossil groups, such as foraminifera and calcareous nannofossils, in Paratethyan areas. In particular, this paper presents a case study of the biostratigraphy of the Grund Formation outcropping at its type locality in Lower Austria. Age attribution of the Grund Formation has been uncertain for some time. The recovery of Praeorbulina glomerosa circularis and Uvigerina macrocarinata, associated with Bolboforma reticulata, allows the correlation of the Grund Formation with the Early Badenian (Middle Miocene). As planktonic foraminifera are generally very rare or absent in shelf deposits of many other Austrian and Moravian Middle Miocene sedimentary sequences, Bolboforma, and in particular B. reticulata, remains an important biomarker to identify lower Badenian sediments.Additionally, the new species Bolboforma gneixendorfensis Spezzaferri &amp; Rögl is described. It is generally double-chambered with a weakly reticulate wall texture and is associated with Bolboforma reticulata, B. bireticulata and/or B. moravica.

scholarly journals A New Preparation Method of Microfauna from Gypsum: Micropaleontological Association from the Middle Miocene Badenian Gypsum Deposits of Paratethys

Geosciences ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 158
Author(s):  
Hans-Peter Bojar ◽  
Claudia Antoniade ◽  
Victor Barbu ◽  
Ana-Voica Bojar
Keyword(s):  
Middle Miocene ◽  
Ammonium Acetate ◽  
Preparation Method ◽  
Planktonic Foraminifera ◽  
Calcareous Algae ◽  
Carpathian Mountains ◽  
Eastern Carpathians ◽  
Calcareous Microfossils ◽  
Microfossil Assemblage ◽  
First Time

Evaporitic gypsum deposits represent an important paleoenvironmental record of the Miocene Badenian of the Carpathian Mountains belt. In this study, we developed a nontoxic method to concentrate calcareous microfossils from gypsum (CaSO4·2H2O), by treating the sulfate with ammonium acetate. We applied the newly developed method to gypsum collected from the Evaporitic Formation outcropping northward of Slănic-Prahova in the Eastern Carpathians. For the first time for this formation, we describe a calcareous microfossil assemblage characterized by the presence of planktonic foraminifera as well as cysts and fragments of calcareous algae.

scholarly journals Gross morphology and microstructure of type locality ossicles of Psephophorus polygonus Meyer, 1847 (Testudines, Dermochelyidae)

2013 ◽  
Vol 150 (5) ◽  
pp. 767-782 ◽  
Author(s):  
MASSIMO DELFINO ◽  
TORSTEN M. SCHEYER ◽  
FRANCESCO CHESI ◽  
TAMARA FLETCHER ◽  
RICHARD GEMEL ◽  
...  
Keyword(s):  
Middle Miocene ◽  
Ventral Surface ◽  
Dive Depth ◽  
Type Locality ◽  
Dermochelys Coriacea ◽  
Compact Layer ◽  
Leatherback Turtle ◽  
New Diagnosis ◽  
First Time ◽  
Growth Centres

AbstractPsephophorus polygonus Meyer, 1847, the first fossil leatherback turtle to be named, was described on the basis of shell ossicles from the middle Miocene (MN6–7/8?) of Slovakia. The whereabouts of this material is uncertain but a slab on display at the Naturhistorisches Museum Wien is considered the neotype. We rediscovered further type locality ossicles in four European institutions, re-evaluated their gross morphology and described for the first time their microstructure by comparing them with Dermochelys coriacea, the only living dermochelyid turtle. The gross morphology is congruent with that already described for P. polygonus, but with two significant exceptions: the ridged ossicles of P. polygonus may have a distinctly concave ventral surface as well as a tectiform shape in cross-section. They do not develop the external keel typical of many ossicles of D. coriacea. Both ridged and non-ridged ossicles of P. polygonus are characterized by compact diploe structures with an internal cortex consisting of a coarse fibrous meshwork, whereas the proportionately thinner ossicles of D. coriacea tend to lose the internal cortex, and thus their diploe, during ontogeny. The ossicles of both P. polygonus and D. coriacea differ from those of other lineages of amniotes whose carapace is composed of polygonal ossicles or platelets, in having growth centres situated at the plate centres just interior to the external bone surface and not within the cancellous core or closer to the internal compact layer. The new diagnosis of P. polygonus allows us to preliminarily re-evaluate the taxonomy of some of the Psephophorus-like species. Despite some macro- and micromorphological differences, it seems likely that Psephophorus was as cosmopolitan as extant Dermochelys and had a broadly similar ecology, with a possible difference concerning the dive depth.

scholarly journals Age determinations of Neogene sediments from the English Channel and Western Approaches

1986 ◽  
Vol 5 (1) ◽  
pp. 5-6
Author(s):  
D. Graham Jenkins ◽  
Erlend Martini
Keyword(s):  
Middle Miocene ◽  
Planktonic Foraminifera ◽  
English Channel ◽  
Calcareous Nannoplankton ◽  
Lower Miocene ◽  
Published Evidence ◽  
Neogene Sediments ◽  
Age Range ◽  
Age Determinations

Abstract. Original published evidence indicated an age range of early Lower Miocene to early Middle Miocene for Globigerina silt samples from the English Channel and the Western Approaches. Suggested younger ages for these samples are refuted on the basis of planktonic foraminifera and calcareous nannoplankton.

A revision of the Neogene Conidae and Conorbidae (Gastropoda) of the Paratethys Sea

Zootaxa ◽  
2016 ◽  
Vol 4210 (1) ◽  
pp. 1 ◽  
Author(s):  
MATHIAS HARZHAUSER ◽  
BERNARD LANDAU
Keyword(s):  
New Species ◽  
Middle Miocene ◽  
Eastern European ◽  
Morphometric Data ◽  
South Eastern ◽  
Tropical Conditions ◽  
Colour Patterns ◽  
Species Descriptions ◽  
First Time ◽  
The Relationship

The Miocene Conidae and Conorbidae of the central- and south-eastern European Paratethys Sea are revised. In total, 74 species are described of which 10 are new species and 5 are documented for the first time from Paratethyan localities. Species descriptions and delimitations are partly based on morphometric data. In addition, colour patterns are described for the first time for the majority of species. In respect to the ongoing discussion on the supraspecific treatment of extant Conidae, we strongly focus on generic allocations and provide a key for the genera as understood herein. Biogeographically, the larger part of the assemblage indicates affiliation with modern western African faunas as indicated by the occurrence of genera such as Lautoconus, Kalloconus, Monteiroconus and Pseudonoduloconus. The relationship with Indo-West Pacific faunas is comparatively low. The high alpha-diversities observed for localities in the Pannonian, Transylvanian and Vienna basins, with up to 44 species, is a marker of tropical conditions in the Paratethys Sea during middle Miocene times.        Conasprella minutissima nov. sp., Kalloconus hendricksi nov. sp., Kalloconus letkesensis nov. sp., Kalloconus pseudohungaricus nov. sp., Lautoconus kovacsi nov. sp., Lautoconus pestensis nov. sp., Lautoconus quaggaoides nov. sp., Leporiconus paratethyianus nov. sp., Plagioconus breitenbergeri nov. sp. and Plagioconus bellissimus nov. sp. are described as new species; Conilithes eichwaldi nov. nom. is proposed as new name for Conus exiguus Eichwald, 1830 [non Lamarck, 1810]. 

scholarly journals Use of nursery areas by the extinct megatooth shark Otodus megalodon (Chondrichthyes: Lamniformes)

2020 ◽  
Vol 16 (11) ◽  
pp. 20200746
Author(s):  
Jose L. Herraiz ◽  
Joan Ribé ◽  
Héctor Botella ◽  
Carlos Martínez-Pérez ◽  
Humberto G. Ferrón
Keyword(s):  
Middle Miocene ◽  
Spatial Scales ◽  
Gaussian Mixture Models ◽  
Marine Species ◽  
Gaussian Mixture ◽  
Size Class ◽  
Class Structure ◽  
Nursery Areas ◽  
First Time ◽  
Slow Growing

Nursery areas are fundamental for the success of many marine species, particularly for large, slow-growing taxa with low fecundity and high age of maturity. Here, we examine the population size-class structure of the extinct gigantic shark Otodus megalodon in a newly described middle Miocene locality from Northeastern Spain, as well as in eight previously known formations (Temblor, Calvert, Pisco, Gatún, Chucunaque, Bahía Inglesa, Yorktown and Bone Valley). In all cases, body lengths of all individuals were inferred from dental parameters and the size-class structure was estimated from kernel probability density functions and Gaussian mixture models. Our analyses support the presence of five potential nurseries ranging from the Langhian (middle Miocene) to the Zanclean (Pliocene), with higher densities of individuals with estimated body lengths within the typical range of neonates and young juveniles. These results reveal, for the first time, that nursery areas were commonly used by O. megalodon over large temporal and spatial scales, reducing early mortality and playing a key role in maintaining viable adult populations. Ultimately, the presumed reliance of O. megalodon on the presence of suitable nursery grounds might have also been determinant in the demise of this iconic top predatory shark.

scholarly journals Els macroforaminífers i la fauna associada del Maastrichtià del sector Prebètic valencià sud (Est de la Península Ibèrica)

2019 ◽  
pp. 55-76
Author(s):  
P. Granero ◽  
R. Robles-Salcedo ◽  
G. Lucena ◽  
L. Troya ◽  
V. Vicedo
Keyword(s):  
Iberian Peninsula ◽  
Upper Cretaceous ◽  
Larger Foraminifera ◽  
Associated Fauna ◽  
Foraminiferal Assemblage ◽  
Foraminiferal Species ◽  
Benthic Foraminiferal Assemblage ◽  
First Time ◽  
Península Ibérica ◽  
Cretaceous Deposits

Larger foraminifera and associated fauna from the Maastrichtian of the southern valencian Prebaetic sector (E Iberian Peninsula) The benthic foraminiferal assemblage and the associated fauna found in the Upper Cretaceous deposits of the Serra de la Solana, Valencia (Spain) have been revised. The study has allowed us to confirm the presence of the foraminiferal species Hellenocyclina beotica Reichel, Siderolites aff. calcitrapoides Lamarck, Orbitoides apiculata Schlumberger, Orbitoides gensacicus (Leymerie) and Omphalocyclus macroporus (Lamarck), as stated by previous authors. In addition, the revision has permitted to identify some other species, never cited before in Serra de la Solana and neighbour regions in Iberian Peninsula, such as Fissoelphidium operculiferum Smout and Selimina cf. spinalis Inan and two different morphotypes of rotaliids that we have left in open nomenclature, namely, Rotaliidae indet. sp. 1 and Rotaliidae indet. sp. 2. The rudists and echinoid found associated to these benthic foraminifera have been also revised. The rudist species found are Hippurites radiosus Des Moulins, Hippurites cornucopiae Defrance, Hippurites cf. lamarcki Douvillé, and Apricardia sp., the two latter cited in Serra de la Solana for the first time. The echinoid assemblage is composed of the species Pygopyrina darderi (Lambert), Linthia payeni (Coquand) and Hemipneustes striatoradiatus (Leske). The whole assemblage, typical of shallow-water platform environments, is Upper Maastrichtian in age and shows some differences in respect other contemporaneous asseblages from other paleogeographical areas.

scholarly journals Re-study of some dinoflagellate cysts from the Oligocene and Miocene of Germany

1984 ◽  
Vol 3 (2) ◽  
pp. 73-94 ◽  
Author(s):  
William A. S. Sarjeant
Keyword(s):  
Middle Miocene ◽  
Type Material ◽  
New Combination ◽  
Late Oligocene ◽  
Dinoflagellate Cysts ◽  
Dinoflagellate Cyst ◽  
Northwest Germany ◽  
Senior Synonym ◽  
First Time

Abstract. The type material of six dinoflagellate cyst species from the Late Oligocene to Middle Miocene of northwest Germany, described originally by Gerlach (1961), is reillustrated and redescribed. It is shown to include representatives of nine species. Areosphaeridium (ex: Baltisphaeridium) pectiniforme is found to be a senior synonym of Areosphaeridium multicornutum Eaton. Systematophora placacantha is considered to be a senior synonym of Cleistosphaeridium (ex: Baltisphaeridium) panniforme (Gerlach). The new combination Rhynchodiniopsis tenuitabulata (Gerlarch) is proposed. Revised diagnoses for these three species and for Leptodinium membranigerum (Gerlach), Achomosphaera triangulata (Gerlach) and Lejeunecysta hyalina (Gerlach) are proposed. The morphology of a form described here for the first time, and tentatively attributed to Phthanoperidinium, is considered perhaps to imply a separate origin for the Phthanoperidiniaceae: for that reason familial, rather than tribal, rank is preferred for that group. The stratigraphical ranges of the nine species here recognised and of two others of Gerlach’s species redescribed in earlier papers are detailed; elimination of misattributed forms means that these ranges are shorter than the published literature suggests.

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