scholarly journals Calcareous nannofossil, ostracode and foraminifera biostratigraphy of Plio-Pleistocene deposits, Rhodes (Greece), with a correlation to the Vrica section (Italy)

2001 ◽  
Vol 20 (2) ◽  
pp. 143-154 ◽  
Author(s):  
Erik Thomsen ◽  
Tine L. Rasmussen ◽  
Annette Hastrup
Keyword(s):  
Deep Water ◽  
Brackish Water ◽  
Southern Italy ◽  
Early Pleistocene ◽  
Calcareous Nannofossil ◽  
Marine Deposits ◽  
First Occurrence ◽  
Degree Of Certainty ◽  
Relative Delay ◽  
Calcareous Nannofossil Biostratigraphy

Abstract. The Kalithea Bay section is situated on the southeastern coast of the island of Rhodes. The section comprises a sedimentary sequence ranging from brackish water gravel and nearshore sand to deep-water clay. The brackish water and nearshore deposits are assigned to the Kritika Formation, while the deep-water deposits are assigned to the Lindos Bay clay. Calcareous nannofossil biostratigraphy shows that the age of the marine sequence is Early Pleistocene. The brackish water sediments cannot be dated with any degree of certainty. The marine deposits are rich in ostracodes and foraminifera and several species have been recognized, which previously have been used as biostratigraphic markers in the Plio-Pleistocene deposits of Rhodes. Biostratigraphic correlation between the Kalithea Bay section and the Plio-Pleistocene boundary stratotype at Vrica, southern Italy, shows that the ostracodes and foraminifera events generally are diachronous relative to the calcareous nannofossil events. The only exception is the first occurrence of the benthic foraminifera Hyalinea balthica. As calcareous nannofossil events are thought to be virtually synchronous within the Mediterranean region, it is concluded that the diachroneity is due to a relative delay in the appearance of ostracodes and foraminifera at Kalithea, caused by differences in the palaeobathymetric settings between the two sites.

scholarly journals Pleistocene Calcareous Nannofossil Biostratigraphy and Gephyrocapsid Occurrence in Site U1431D, IODP 349, South China Sea

Geosciences ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 388
Author(s):  
Jose Dominick S. Guballa ◽  
Alyssa M. Peleo-Alampay
Keyword(s):  
South China Sea ◽  
South China ◽  
Emiliania Huxleyi ◽  
Calcareous Nannofossil ◽  
Local Climate ◽  
China Sea ◽  
Climate Anomalies ◽  
First Occurrence ◽  
Calcareous Nannofossil Biostratigraphy ◽  
Morphologic Changes

We reinvestigated the Pleistocene calcareous nannofossil biostratigraphy of Site U1431D (International Ocean Discovery Program (IODP) Expedition 349) in the South China Sea (SCS). Twelve calcareous nannofossil Pleistocene datums are identified in the site. The analysis confirms that the last occurrence (LO) of Calcidiscus macintyrei is below the first occurrence (FO) of large Gephyrocapsa spp. (>5.5 μm). The FO of medium Gephyrocapsa spp. (4–5.5 μm) is also identified in the samples through morphometric measurements, which was unreported in shipboard results. Magnetobiochronologic calibrations of the numerical ages of LO of Pseudoemiliania lacunosa and FO of Emiliania huxleyi are underestimated and need reassessment. Other potential markers such as a morphological turnover of circular to elliptical variants of Pseudoemiliania lacunosa and a small Gephyrocapsa acme almost synchronous with the FO of Emiliania huxleyi may offer biostratigraphic significance in the SCS. The morphologic changes in Gephyrocapsa coccoliths are also examined for the first time in Site U1431D. Placolith length and bridge angle changes are comparable with other ocean basins, suggesting that morphologic changes are most likely evolutionary novelties rather than being caused by local climate anomalies.

scholarly journals Biostratigraphic constraints of the Early Toarcian Oceanic Anoxic Event: new data from calcareous nannofossil investigations of Boreal and Tethyan sections

2019 ◽  
Author(s):  
Stefano Visentin ◽  
Elisabetta Erba ◽  
Joerg Mutterlose
Keyword(s):  
Calcareous Nannofossil ◽  
Northern Germany ◽  
Lower Saxony ◽  
Oceanic Anoxic Event ◽  
Anoxic Event ◽  
First Occurrence ◽  
Calcareous Nannofossil Biostratigraphy ◽  
Posidonia Shale ◽  
Boreal Realm ◽  
Interval Expression

Calcareous nannofossil biostratigraphy was carried out in Upper Pliensbachian – Lower Toarcian sediments, which cover the Toarcian Oceanic Anoxic Event (T-OAE) interval. In particular, semiquantitative analyses were performed on a total of 156 samples in the composite Sogno Core (Lombardy Basin, Southern Alps) representing a pelagic Tethyan section. Quantitative investigations were applied to additional 168 samples across the Amaltheenton Fm. and Posidonienschiefer Fm., from two cores of the Boreal Realm (Lower Saxony Basin, northern Germany). Primary and secondary events of the Tethyan and Boreal zonations were recognized, allowing the identifications of the NJT5, NJT6 nannofossil Zones for the Sogno Core and the NJ5, NJ6, NJ7 Zones for the German sections, respectively. The sequence of nannofossil biohorizons is generally consistent with data available for various areas at lower and higher latitudes, confirming their reproducibility and reliability for intra and inter-regional correlations. Geochemistry evidences the presence of the negative C isotopic excursion across the “Fish Level” black shale interval expression of the T-OAE in the Sogno Core. The same anomaly is recorded in the German successions at the base of the Posidonia Shale witnessing the passage from well oxygenated to predominantly anoxic conditions. Our results show that the T-OAE C isotopic excursion recorded in the Sogno Core is excellently constrained by the first occurrence (FO) of Carinolithus superbus at the onset and the last occurrence (LO) of Mitrolithus jansae at the end. A significant decrease in abundance and size of Schizosphaerella punctulata (the “S. punctulata crisis”) and an abundance drop of M. jansae further characterise the T-OAE perturbation. Only S. punctulata shows a recovery at the end of the T-OAE, while M. jansae barely survived the palaeoenviromental stress and disappeared soon after its termination. The extreme rareness of S. punctulata and the absence of M. jansae in the Boreal Realm prevent the recognition of the “S. punctulata crisis” and the M. jansae decline. Our study reveals the LO of Biscutum finchii together with the FO of C. superbus as an additional event approximating the onset of the C isotopic excursion exclusively in the German successions. Further events, such as the LOs of Biscutum grandis, Crepidolithus granulatus and Parhabdolithus liasicus are detected within the C isotopic anomaly exclusively in the German sections. Nannofossil biostratigraphy permits the effective dating and correlating of Early Jurassic major palaeoceanographic events and particularly of the T-OAE which are of a great importance to derive a definitive model for the Posidonia Shale deposition.

Latest Villafranchian climate and landscape reconstructions at Pirro Nord (southern Italy)

Geology ◽  
2019 ◽  
Vol 47 (9) ◽  
pp. 829-832 ◽  
Author(s):  
Hugues-Alexandre Blain ◽  
Ana Fagoaga ◽  
Francisco Javier Ruiz-Sánchez ◽  
Josep Francesc Bisbal-Chinesta ◽  
Massimo Delfino
Keyword(s):  
Southern Italy ◽  
Numerical Data ◽  
Summer Rainfall ◽  
Distribution Patterns ◽  
Early Pleistocene ◽  
Mean Annual Precipitation ◽  
Mean Annual Temperature ◽  
Climate Conditions ◽  
First Occurrence ◽  
The Mean

Abstract Early Pleistocene terrestrial climate conditions in the Mediterranean region, especially between 1.3 and 1.7 Ma, are poorly understood. Here, the amphibian and reptile fossil record from 24 fissures (Cava Pirro) of the Pirro Nord karstic complex (southern Italy) is used to infer quantitative paleoclimatic and paleoenvironmental reconstructions. These numerical data indicate that the mean annual temperature may have been somewhat lower (–1.6 to –3.6 °C compared to modern temperatures) than that of today, and the mean annual precipitation slightly higher (+90 to +240 mm) than modern values. Seasonality was more pronounced, with cooler summers (–0.4 to –2.0 °C) and much colder winters (–1.2 to –6.0 °C). Rainfall distribution patterns during the year show more precipitation during the winter (+14 to +43 mm), with quantities of summer rainfall (–1.7 to +6.6 mm) being similar to modern values. The associated landscape comprised an open dry environment with scattered patches of woodland, locally along water courses or around swamps. This ecological scenario fits with early Pleistocene cold conditions, where the first occurrence of some eastern emigrants suggests a scenario of trans-Adriatic dispersal, as may have also occurred for the earliest European hominins.

scholarly journals Quantative calcareous nannofossil biostratigraphy of Bay Akrotiri section (Cefallinia island, W. Greece). Tracing the gephyrocapsid size-trend in an early Pleistocene terrigenous sequence

2018 ◽  
Vol 34 (2) ◽  
pp. 645 ◽  
Author(s):  
M. V. TRIANTAPHYLLOU
Keyword(s):  
Quantitative Analysis ◽  
Distribution Patterns ◽  
Early Pleistocene ◽  
Calcareous Nannofossil ◽  
Evolutionary Lineage ◽  
Calcareous Nannofossil Biostratigraphy ◽  
Terrigenous Sequence

Bay Akrotiri section represents a thick terrigenous sequence laying along the southern part of Paliki peninsula (southwest Cefallinia). The data of the calcareous nannofossil quantitative analysis indicate that the studied sediments are ranging in terms of age between 1.95 Ma and 1.238 Ma approximately. The provided distribution patterns clearly depict an apparent evolutionary lineage close to the Plio/Pleistocene boundary, from small Gephyrocapsa placoliths to larger forms of gephyrocapsids.

scholarly journals Biostratigraphic constraints of the Early Toarcian Oceanic Anoxic Event: new data from calcareous nannofossil investigations of Boreal and Tethyan sections

2019 ◽  
Author(s):  
Stefano Visentin ◽  
Elisabetta Erba ◽  
Joerg Mutterlose
Keyword(s):  
Calcareous Nannofossil ◽  
Northern Germany ◽  
Lower Saxony ◽  
Oceanic Anoxic Event ◽  
Anoxic Event ◽  
First Occurrence ◽  
Calcareous Nannofossil Biostratigraphy ◽  
Posidonia Shale ◽  
Boreal Realm ◽  
Interval Expression

Calcareous nannofossil biostratigraphy was carried out in Upper Pliensbachian – Lower Toarcian sediments, which cover the Toarcian Oceanic Anoxic Event (T-OAE) interval. In particular, semiquantitative analyses were performed on a total of 156 samples in the composite Sogno Core (Lombardy Basin, Southern Alps) representing a pelagic Tethyan section. Quantitative investigations were applied to additional 168 samples across the Amaltheenton Fm. and Posidonienschiefer Fm., from two cores of the Boreal Realm (Lower Saxony Basin, northern Germany). Primary and secondary events of the Tethyan and Boreal zonations were recognized, allowing the identifications of the NJT5, NJT6 nannofossil Zones for the Sogno Core and the NJ5, NJ6, NJ7 Zones for the German sections, respectively. The sequence of nannofossil biohorizons is generally consistent with data available for various areas at lower and higher latitudes, confirming their reproducibility and reliability for intra and inter-regional correlations. Geochemistry evidences the presence of the negative C isotopic excursion across the “Fish Level” black shale interval expression of the T-OAE in the Sogno Core. The same anomaly is recorded in the German successions at the base of the Posidonia Shale witnessing the passage from well oxygenated to predominantly anoxic conditions. Our results show that the T-OAE C isotopic excursion recorded in the Sogno Core is excellently constrained by the first occurrence (FO) of Carinolithus superbus at the onset and the last occurrence (LO) of Mitrolithus jansae at the end. A significant decrease in abundance and size of Schizosphaerella punctulata (the “S. punctulata crisis”) and an abundance drop of M. jansae further characterise the T-OAE perturbation. Only S. punctulata shows a recovery at the end of the T-OAE, while M. jansae barely survived the palaeoenviromental stress and disappeared soon after its termination. The extreme rareness of S. punctulata and the absence of M. jansae in the Boreal Realm prevent the recognition of the “S. punctulata crisis” and the M. jansae decline. Our study reveals the LO of Biscutum finchii together with the FO of C. superbus as an additional event approximating the onset of the C isotopic excursion exclusively in the German successions. Further events, such as the LOs of Biscutum grandis, Crepidolithus granulatus and Parhabdolithus liasicus are detected within the C isotopic anomaly exclusively in the German sections. Nannofossil biostratigraphy permits the effective dating and correlating of Early Jurassic major palaeoceanographic events and particularly of the T-OAE which are of a great importance to derive a definitive model for the Posidonia Shale deposition.

scholarly journals Early-Middle Miocene from Kotaphi hill section (Nicosia, Cyprus): preliminary biostratigraphy and paleoceanographic implications

2016 ◽  
Vol 47 (1) ◽  
pp. 62
Author(s):  
M. Athanasiou ◽  
M. Triantaphyllou ◽  
M. Dimiza ◽  
A. Gogou ◽  
I. Bouloubassi ◽  
...  
Keyword(s):  
High Resolution ◽  
Key Words ◽  
Middle Miocene ◽  
High Abundance ◽  
Common Occurrence ◽  
Calcareous Nannofossil ◽  
Preliminary Results ◽  
Marine Deposits ◽  
Total Absence ◽  
Calcareous Nannofossil Biostratigraphy

Calcareous nannofossil biostratigraphy from Kotaphi Hill section allowed not only the biostratigraphic zonation of the Miocene units but also provided evidence for a distinct warm phase known as the Middle Miocene Climate Optimum (MMCO). Kotaphi Hill section is located in Agrokipia village (Nicosia region, Cyprus) and consists of cyclic marine deposits of the Pakhna Formation. High resolution sampling has been conducted and 84 samples were collected. Preliminary results indicated that several important calcareous nannofossil events can be consistently recognized along the studied section. High abundances of Discoaster druggii and Highest occurrence (HO) of Sphenolithus procerus suggest the presence of NN2 biozone while, LO of Sphenolithus belemnos has been used to recognize the base of biozone NN3. Upwards, Lowest Common Occurrence (LCO) of Sphenolithus heteromorphus marked the NN3-4 boundary-level. Biozone NN4 in Kotaphi Hill section is featured by high abundance of S. heteromorphus whereas total absence of the species together with the LO of Helicosphaera walbedorfensis mark the Paracme Beginning (PB) of S. heteromorphus interval. High abundance of warm indicators such as Discoasterids, S. heteromorphus, S. moriformis and Helicosphaera carteri observed in our material may partly reflect the warm phase of MMCO. Key words: Agrokipia village, Pakhna Formation, Cyprus, Sphenolithus heteromorphus, Middle Miocene Climate Optimum.

scholarly journals Last snails standing since the Early Pleistocene, a tale of Calliostomatidae (Gastropoda) living in deep-water coral habitats in the north-eastern Atlantic

Zootaxa ◽  
2019 ◽  
Vol 4613 (1) ◽  
pp. 93-110
Author(s):  
LEON HOFFMAN ◽  
LYDIA BEUCK ◽  
BART VAN HEUGTEN ◽  
MARC LAVALEYE ◽  
ANDRÉ FREIWALD
Keyword(s):  
Atlantic Ocean ◽  
Mediterranean Sea ◽  
Deep Water ◽  
Southern Italy ◽  
Early Pleistocene ◽  
Ne Atlantic ◽  
The North ◽  
North Eastern ◽  
Ne Atlantic Ocean ◽  
Water Coral

Three species in the gastropod genus Calliostoma are confirmed as living in Deep-Water Coral (DWC) habitats in the NE Atlantic Ocean: Calliostoma bullatum (Philippi, 1844), C. maurolici (Seguenza, 1876) and C. leptophyma Dautzenberg & Fischer, 1896. Up to now, C. bullatum was only known as fossil from Early to Mid-Pleistocene outcrops in DWC-related habitats in southern Italy; our study confirmed its living presence in DWC off Mauritania. A discussion is provided on the distribution of DWC-related calliostomatids in the NE Atlantic and the Mediterranean Sea from the Pleistocene to the present. 

Bio- and lithostratigraphy of lower Pleistocene marine successions in western Emilia (Italy) and their implications for the first occurrence of Arctica islandica in the Mediterranean Sea

2019 ◽  
Vol 92 (2) ◽  
pp. 549-569 ◽  
Author(s):  
Gaia Crippa ◽  
Michele Azzarone ◽  
Cinzia Bottini ◽  
Stefania Crespi ◽  
Fabrizio Felletti ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Depositional Environment ◽  
Early Pleistocene ◽  
Calcareous Nannofossil ◽  
Arctica Islandica ◽  
Ecological Requirements ◽  
Lower Pleistocene ◽  
First Occurrence ◽  
The Mediterranean ◽  
First Time

AbstractThe Arda and Stirone marine successions (Italy) represent key sections for the early Pleistocene; they were deposited continuously within a frame of climate change, recording the Calabrian cooling as testified by the occurrence of the “northern guests,” such as the bivalve Arctica islandica. In addition, although the first occurrence of A. islandica in the Mediterranean Sea was used as the main criterion to mark the former Pliocene-Pleistocene boundary, the age of this bioevent was never well constrained. Here, we describe the Stirone depositional environment and constrain for the first time the section age using calcareous nannofossil and foraminifera biostratigraphy. We also correlate the Arda and Stirone sections using complementary biostratigraphic and magnetostratigraphic data. Our results indicate that A. islandica first occurred in both the successions slightly below the top of the CNPL7 biozone (dated at 1.71 Ma). Comparisons with other lower Pleistocene Mediterranean marine successions indicate that the stratigraphically lowest level where A. islandica first occurred in the Mediterranean Sea is in the Arda and Stirone sections; these environments satisfied the ecological requirements for the establishment and the proliferation of the species, which only subsequently (late Calabrian) has been retrieved in southern Italy and other areas of the Mediterranean Sea.

scholarly journals LATE MIOCENE CALCAREOUS NANNOFOSSIL STRATIGRAPHY AND BIOEVENTS CORRELATION: KALIDONIA CASE SECTION (NW CRETE, GREECE)

2018 ◽  
Vol 40 (1) ◽  
pp. 1
Author(s):  
S. Bellas ◽  
D. Frydas ◽  
H. Keupp
Keyword(s):  
Deep Water ◽  
Late Miocene ◽  
Messinian Salinity Crisis ◽  
Calcareous Nannofossils ◽  
Calcareous Nannofossil ◽  
Type Section ◽  
First Occurrence ◽  
Upper Tortonian ◽  
Depositional Cycle ◽  
Quantitative Approaches

Calcareous nannofossils are widely used for biostratigraphic correlations. Quantitative approaches enable better understanding of reliability of bioevents. In order to refine the late Miocene stratigraphy ofNW Crete, the deposits of Kalidonia basin along its type section are here investigated. It was possible to distinguish the Tortonian/Messinian boundary by NNlla & NNllb, CN9a & CN9b, MNNlla & MNNllb biozones. Reticulofenestra pseudoumbilicus PB (Paracme Beginning) and R. rotaria FO (First Occurrence) proved to act as additional significant biohorizons improving the stratigraphie evolution of the studied paleobasin and providing a tight biochronologic framework. The Kalidonia section fully covers an undisturbed marine depositional cycle from the upper Tortonian to upper Messinian, where a predominant deep water fades (DWF) is followed by transitional sediments (TF) and the sequence closes at the top by a reefal-bioclastic fades (RF) relative to the 'Calcare di Base ' in Italy indicating the 'Messinian Salinity Crisis Event.

Earliest Miocene calcareous nannofossil biostratigraphy from the low-latitude Pisco Basin (Peru)

Stratigraphy ◽  
2019 ◽  
Vol 16 (2) ◽  
pp. 87-105
Author(s):  
Emilia R. Belia ◽  
Kevin E. Nick ◽  
Erika Bedoya Agudelo ◽  
David K. Watkins
Keyword(s):  
Calcareous Nannofossil ◽  
Low Latitude ◽  
Calcareous Nannofossil Biostratigraphy
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