THE USE OF CARBON AND OXYGEN STABLE ISOTOPES IN THE STUDY OF GLOBAL PALAEOCEANOGRAPHIC CHANGES: EXAMPLES FROM THE CRETACEOUS SEDIMENT ROCKS OF WESTERN GREECE

In the present paper we examine the use of carbon and oxygen stable isotopes in the study of global palaeoceanographic changes, with special reference to the oceanic anoxic events (OAEs). The analysis of stable isotopes was applied to the examination of Cretaceous sediments from the Ionian and Pindos zones of Western Greece. In the Ionian zone the carbon and oxygen stable isotopes, combined with biostratigraphic data, record the palaeoenvironmental change corresponding to the anoxic events Bonarelli (Cenomanian/Turonian, OAE2) and Paquier (Lower Albian, OAE1b). In the Pindos zone, within the Cretaceous sediments, we observed two organic-carbon-rich levels. According to the biostratigraphic and isotopie analysis, the first level corresponds to an OAE of Santonian age. This local oceanic anoxic event is described for the first time. The second level, Aptian - Albian age, possibly correlates to either the Paquier event (OAE 1b) or the Selli event (OAE 1a), which in Greece were until now known only in the Ionian zone.

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CRETACEOUS OCEANIC ANOXIC EVENTS IN WESTERN CONTINENTAL GREECE

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.16832 ◽

2018 ◽

Vol 36 (2) ◽

pp. 846 ◽

Cited By ~ 4

Author(s):

V. Karakitsios ◽

H. Tsikos ◽

Y. Van Breugel ◽

I. Bakopoulos ◽

L. Koletti

Keyword(s):

Black Shale ◽

Oceanic Anoxic Event ◽

Anoxic Event ◽

Anoxic Events ◽

Organic Sediments ◽

Preliminary Study ◽

Western Greece

Integrated chemostratigraphy and biostratigraphy in Cretaceous pelagic carbonate successions and associated organic sediments of the Ionian basin (western Greece) show the first documentation of the Cenomanian Turonian (OAE)2 and Lower Albian (OAE)1b Oceanic Anoxic Events from western Greece. Preliminary study of the Pindos basin (western Greece) has also identified a black shale horizon which may corresponds to the Lower Albian (OAE)1b Oceanic Anoxic Event.

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Thrombolitic and coral buildups in the Upper Albian of the Fahdene basin (North Tunisia): stratigraphy, sedimentology and genesis

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.183.3.217 ◽

2012 ◽

Vol 183 (3) ◽

pp. 217-231 ◽

Cited By ~ 4

Author(s):

Mohsen Layeb ◽

Moez Ben Fadhel ◽

Mohamed Ben Youssef

Keyword(s):

Small Scale ◽

Original Structure ◽

Carbonate Precipitation ◽

Anoxic Zone ◽

Northern Tunisia ◽

Oceanic Anoxic Event ◽

Internal Structures ◽

Anoxic Event ◽

Anoxic Environment ◽

First Time

Abstract Within the Upper Albian marl/limestone pelagic to hemi-pelagic successions of Fahdene basin (northern Tunisia), small-scale thrombolitic and coral buildups were recognized for the first time. The exceptionally well-exposed and well-preserved buildups (i.e. Oued Siliana and Jebel Srassif buildups) were investigated for their biostratigraphic, petrographic, and genesis character. The vertical succession is characterized as shallowing upward and comprise four to nine conical and/or lenticular bioherms/biostromes (up to 4 m in diameter). Basal buildups consist of four to six deep water microbial thrombolites and are generally associated with the uppermost organic-rich black shale of the Mouelha member which corresponds to the Oceanic Anoxic Event OAE1d. These buildups change stratigraphic upward into three hermatypic hexacorallian thrombolites with abundant fossils and bioturbation traces. The geometry and the observed internal structures of the thrombolites suggest that microbial activity thrived carbonate precipitation and subsequent lithification, which in turn favoured preservation of the original structure of the buildups. The microbial thrombolites formed within or near the anoxic zone (related to the Oceanic Anoxic Event OAE1d) whereas the coral thrombolites grew in the photic zone. We suggest that the onset of the microbial thrombolites was induced by the presence of an eutrophic, hypersaline, and anoxic environment which is enhanced by the Late Albian sea level rise. Nevertheless, flourishing of metazoans that lead to the coral thrombolites was associated with an oxygenated and oligotrophic environment. Halokinetic dynamics and tilted-block fault systems provided conduits for nutrient-rich fluids and hydrocarbons which fueled chemosynthetic-based communities.

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Corrigendum to “High resolution osmium data record three distinct pulses of magmatic activity during cretaceous Oceanic Anoxic Event 2 (OAE-2)” [Geochim. Cosmochim. Acta 285 (2020) 257–273]

Geochimica et Cosmochimica Acta ◽

10.1016/j.gca.2020.09.022 ◽

2020 ◽

Vol 290 ◽

pp. 424-425

Author(s):

Daniel L. Sullivan ◽

Alan D. Brandon ◽

James Eldrett ◽

Steven C. Bergman ◽

Shawn Wright ◽

...

Keyword(s):

High Resolution ◽

Magmatic Activity ◽

Oceanic Anoxic Event ◽

Oceanic Anoxic Event 2 ◽

Anoxic Event ◽

Data Record

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Progressive palaeoenvironmental change during the Late Barremian–Early Aptian as prelude to Oceanic Anoxic Event 1a: Evidence from the Gorgo a Cerbara section (Umbria-Marche basin, central Italy)

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2011.01.025 ◽

2011 ◽

Vol 302 (3-4) ◽

pp. 396-406 ◽

Cited By ~ 66

Author(s):

Melody Stein ◽

Karl B. Föllmi ◽

Stéphane Westermann ◽

Alexis Godet ◽

Thierry Adatte ◽

...

Keyword(s):

Central Italy ◽

Oceanic Anoxic Event ◽

Palaeoenvironmental Change ◽

Anoxic Event

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Time series analysis (orbital cycles) of the uppermost Cenomanian-Lower Turonian sequence on the southern Tethyan margin using foraminifera

Geologica Carpathica ◽

10.2478/v10096-010-0004-5 ◽

2010 ◽

Vol 61 (2) ◽

pp. 111-120 ◽

Cited By ~ 5

Author(s):

Mohamed Soua

Keyword(s):

Time Series ◽

Time Series Analysis ◽

Oceanic Anoxic Event ◽

Series Analysis ◽

Orbital Cycles ◽

Anoxic Event ◽

Minimum Zone ◽

First Time ◽

Shed Light ◽

Oxygen Minimum

Time series analysis (orbital cycles) of the uppermost Cenomanian-Lower Turonian sequence on the southern Tethyan margin using foraminiferaTime series analysis has been performed for the first time on the Cenomanian-Turonian sequence in Central Tunisia in order to shed light on its Milankovitch-like cyclicity. This analysis was applied to two foraminiferal genera: the biserialHeterohelix, an oxygen-minimum zone (OMZ) dweller, and the triserialGuembelitria, a eutrophic surface dweller. Average sedimentary rates and the duration of the oceanic anoxic event (OAE2) in each studied section were estimated. The fluctuations in abundance of these two opportunistic species can be related mainly to both precessional (ca. 20 kyr) and eccentricity (100 and 400 kyr) cyclicity suggesting that changes in surface water fertility were linked to climate changes in the Milankovitch frequency band.

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Global controls on phosphatization of fossils during the toarcian oceanic anoxic event

Scientific Reports ◽

10.1038/s41598-021-03482-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sinjini Sinha ◽

A. D. Muscente ◽

James D. Schiffbauer ◽

Matt Williams ◽

Günter Schweigert ◽

...

Keyword(s):

Lower Jurassic ◽

X Ray ◽

Oceanic Anoxic Event ◽

Exceptional Preservation ◽

Level Change ◽

Environmental Controls ◽

Anoxic Basins ◽

Anoxic Event ◽

Anoxic Events ◽

Posidonia Shale

AbstractKonservat-Lagerstätten—deposits with exceptionally preserved fossils—vary in abundance across geographic and stratigraphic space due to paleoenvironmental heterogeneity. While oceanic anoxic events (OAEs) may have promoted preservation of marine lagerstätten, the environmental controls on their taphonomy remain unclear. Here, we provide new data on the mineralization of fossils in three Lower Jurassic Lagerstätten—Strawberry Bank (UK), Ya Ha Tinda (Canada), and Posidonia Shale (Germany) —and test the hypothesis that they were preserved under similar conditions. Biostratigraphy indicates that all three Lagerstätten were deposited during the Toarcian OAE (TOAE), and scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) show that each deposit contains a variety of taxa preserved as phosphatized skeletons and tissues. Thus, despite their geographic and paleoenvironmental differences, all of these Lagerstätten were deposited in settings conducive to phosphatization, indicating that the TOAE fostered exceptional preservation in marine settings around the world. Phosphatization may have been fueled by phosphate delivery from climatically-driven sea level change and continental weathering, with anoxic basins acting as phosphorus traps.

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The Late Hauterivian Faraoni ‘Oceanic Anoxic Event’: an update

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.185.6.359 ◽

2014 ◽

Vol 185 (6) ◽

pp. 359-377 ◽

Cited By ~ 6

Author(s):

François Baudin ◽

Laurent Riquier

Keyword(s):

Middle Part ◽

Time Interval ◽

Oceanic Anoxic Event ◽

Anoxic Event ◽

Anoxic Events ◽

The Mediterranean ◽

Definition Of ◽

Geochemical Studies ◽

New Occurrences

AbstractMost oceanic anoxic events (OAEs) took place during the middle part of the Cretaceous and the Late Hauterivian probably recorded the first anoxic event within this peculiar time interval. The so-called Faraoni event (~131 Ma) was initially defined as a short-lived anoxic event restricted to the Mediterranean domain. Since its recognition, numerous geochemical studies were conducted on the Faraoni event and new occurrences of this event were suggested outside the Tethyan domain. This paper presents an update on the Late Hauterivian Faraoni event and examines if this event agrees with the definition of OAEs.

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Palaeoepidemiology in extinct vertebrate populations: factors influencing skeletal health in Jurassic marine reptiles

Royal Society Open Science ◽

10.1098/rsos.190264 ◽

2019 ◽

Vol 6 (7) ◽

pp. 190264 ◽

Cited By ~ 2

Author(s):

Judith M. Pardo-Pérez ◽

Benjamin Kear ◽

Erin E. Maxwell

Keyword(s):

A Priori ◽

Skeletal Health ◽

Oceanic Anoxic Event ◽

Skeletal Injury ◽

Individual Health ◽

Marine Reptiles ◽

Factors Influencing ◽

Palaeoenvironmental Change ◽

Anoxic Event ◽

Ecosystem Level

Palaeoepidemiological studies related to palaeoecology are rare, but have the potential to provide information regarding ecosystem-level characteristics by measuring individual health. In order to assess factors underlying the prevalence of pathologies in large marine vertebrates, we surveyed ichthyosaurs (Mesozoic marine reptiles) from the Posidonienschiefer Formation (Early Jurassic: Toarcian) of southwestern Germany. This Formation provides a relatively large sample from a geologically and geographically restricted interval, making it ideal for generating baseline data for a palaeoepidemiological survey. We examined the influence of taxon, anatomical region, body size, ontogeny and environmental change, as represented by the early Toarcian Oceanic Anoxic Event, on the prevalence of pathologies, based on a priori ideas of factors influencing population skeletal health. Our results show that the incidence of pathologies is dependent on taxon, with the small-bodied genus Stenopterygius exhibiting fewer skeletal pathologies than other genera. Within Stenopterygius , we detected more pathologies in large adults than in smaller size classes. Stratigraphic horizon, a proxy for palaeoenvironmental change, did not influence the incidence of pathologies in Stenopterygius . The quantification of the occurrence of pathologies within taxa and across guilds is critical to constructing more detailed hypotheses regarding changes in the prevalence of skeletal injury and disease through Earth history.

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Extent and duration of marine anoxia during the Frasnian–Famennian (Late Devonian) mass extinction in Poland, Germany, Austria and France

Geological Magazine ◽

10.1017/s0016756804008866 ◽

2004 ◽

Vol 141 (2) ◽

pp. 173-193 ◽

Cited By ~ 151

Author(s):

DAVID BOND ◽

PAUL B. WIGNALL ◽

GRZEGORZ RACKI

Keyword(s):

Gamma Ray ◽

Gamma Ray Spectrometry ◽

Late Devonian ◽

Oceanic Anoxic Event ◽

Fabric Analysis ◽

Anoxic Event ◽

Anoxic Events ◽

Frasnian Stage ◽

Early Late ◽

Sediment Fabric

The intensity and extent of anoxia during the two Kellwasser anoxic events has been investigated in a range of European localities using a multidisciplinary approach (pyrite framboid assay, gamma-ray spectrometry and sediment fabric analysis). The results reveal that the development of the Lower Kellwasser Horizon in the early Late rhenana Zone (Frasnian Stage) in German type sections does not always coincide with anoxic events elsewhere in Europe and, in some locations, seafloor oxygenation improves during this interval. Thus, this anoxic event is not universally developed. In contrast, the Upper Kellwasser Horizon, developed in the Late linguiformis Zone (Frasnian Stage) in Germany correlates with a European-wide anoxic event that is manifest as an intensification of anoxia in basinal locations to the point that stable euxinic conditions were developed (for example, in the basins of the Holy Cross Mountains, Poland). The interval also saw the spread of dysoxic waters into very shallow water (for instance, reefal) locations, and it seems reasonable to link the contemporaneous demise of many marine taxa to this phase of intense and widespread anoxia. In basinal locations, euxinic conditions persisted into the earliest Famennian with little change of depositional conditions. Only in the continental margin location of Austria was anoxia not developed at any time in the Late Devonian. Consequently it appears that the Upper Kellwasser anoxic event was an epicontinental seaway phenomenon, caused by the upward expansion of anoxia from deep basinal locales rather than an ‘oceanic’ anoxic event that has spilled laterally into epicontinental settings.

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