Earth:Cenomanian-Turonian boundary event

From HandWiki
Short description: Anoxic extinction event in the Cretaceous period
System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Paleogene Paleocene Danian younger
Cretaceous Upper/
Late
Maastrichtian 66.0 72.1
Campanian 72.1 83.6
Santonian 83.6 86.3
Coniacian 86.3 89.8
Turonian 89.8 93.9
Cenomanian 93.9 100.5
Lower/
Early
Albian 100.5 ≈113.0
Aptian ≈113.0 ≈125.0
Barremian ≈125.0 ≈129.4
Hauterivian ≈129.4 ≈132.9
Valanginian ≈132.9 ≈139.8
Berriasian ≈139.8 ≈145.0
Jurassic Upper/
Late
Tithonian older
Subdivision of the Cretaceous system
according to the ICS, as of 2017.[1]

The Cenomanian-Turonian boundary event, also known as the Cenomanian-Turonian extinction, Cenomanian-Turonian oceanic anoxic event (OAE 2), and referred to also as the Bonarelli event,[2] was one of two anoxic extinction events in the Cretaceous period. (The other being the earlier Selli event, or OAE 1a, in the Aptian.[3]) The Cenomanian-Turonian oceanic anoxic event is considered to be the most recent truly global oceanic anoxic event in Earth's geologic history.[4] Selby et al. in 2009 concluded the OAE 2 occurred approximately 91.5 ± 8.6 Ma,[5] though estimates published by Leckie et al. (2002) are given as 93–94 Ma.[6] The Cenomanian-Turonian boundary has been refined in 2012 to 93.9 ± 0.15 Ma.[7] There was a large carbon cycle disturbance during this time period,[8][9] signified by a large positive carbon isotope excursion.[10][11][12] However, apart from the carbon cycle disturbance, there were also large disturbances in the ocean's nitrogen,[13] oxygen,[14] phosphorus,[15][16][17] sulphur,[18] and iron cycles.[19]

Background

The Cenomanian and Turonian stages were first noted by D'Orbigny between 1843 and 1852. The global type section for this boundary is located in the Bridge Creek Limestone Member of the Greenhorn Formation near Pueblo, Colorado, which are bedded with the Milankovitch orbital signature. Here, a positive carbon-isotope event is clearly shown, although none of the characteristic, organic-rich black shale is present. It has been estimated that the isotope shift lasted approximately 850,000 years longer than the black shale event, which may be the cause of this anomaly in the Colorado type section.[20] A significantly expanded OAE2 interval from southern Tibet documents a complete, more detailed, and finer-scale structures of the positive carbon isotope excursion that contains multiple shorter-term carbon isotope stages amounting to a total duration of 820 ±25 ka.[21]

The level is also known as the Bonarelli event because of 1-to-2-metre (3 ft 3 in to 6 ft 7 in) layer of thick, black shale that marks the boundary and was first studied by Guido Bonarelli (it) in 1891.[22] It is characterized by interbedded black shales, chert and radiolarian sands and is estimated to span a 400,000-year interval. Planktonic foraminifera do not exist in this Bonarelli level, and the presence of radiolarians in this section indicates relatively high productivity and an availability of nutrients.[23] In the Western Interior Seaway, the Cenomanian-Turonian boundary event is associated with the Benthonic Zone, characterised by a higher density of benthic foraminifera relative to planktonic foraminifera, although the timing of the appearance of the Benthonic Zone is not uniformly synchronous with the onset of the oceanic anoxic event and is thus cannot be used to consistently demarcate its beginning.[24]

Timeline

The total duration of OAE2 has been estimated at 0.82 ± 0.025 Myr[21] or 0.71 ± 0.17 Myr.[25] At high latitudes, the event lasted for a shorter time: only ~600 kyr.[26] Biodiversity patterns of planktic foraminifera indicate that the Cenomanian-Turonian extinction occurred in five phases. Phase I, which took place from 313,000 to 55,000 years before the onset of the anoxic event, witnessed a stratified water column and high planktonic foraminiferal diversity, suggesting a stable marine environment. Phase II, characterised by significant environmental perturbations, lasted from 55,000 years before OAE2 until its onset and witnessed a decline in rotaliporids and heterohelicids, a zenith of schackoinids and hedbergellids, a 'large form eclipse' during which foraminifera exceeding 150 microns disappeared, and the start of a trend of dwarfism among many foraminifera. This phase also saw an enhanced oxygen minimum zone and increased productivity in surface waters. Phase III lasted for 100,000 to 900,000 years and was coincident with the Bonarelli Level's deposition and exhibited extensive proliferation of radiolarians, indicative of extremely eutrophic conditions. Phase IV lasted for around 35,000 years and was most notable for the increase in the abundance of hedbergellids and schackoinids, being extremely similar to Phase II, with the main difference being that rotaliporids were absent from Phase IV. Phase V was a recovery interval lasting 118,000 years and marked the end of the 'large form eclipse' that began in Phase II; heterohelicids and hedbergellids remained in abundance during this phase, pointing to continued environmental disturbance during this phase.[27]

Causes

Climate change

Earth pronouncedly warmed just before the beginning of OAE2.[28] The Cenomanian-Turonian interval represents one of the hottest intervals of the entire Phanerozoic eon,[29] and it boasted the highest carbon dioxide concentrations of the Cretaceous period.[30] Even before OAE2, during the late Cenomanian, tropical sea surface temperatures (SSTs) were very warm, about 27-29 °C.[31] The onset of OAE2 was concurrent with a 4-5 °C rise in shelf sea temperatures.[32] Mean tropical SSTs during OAE2 have been conservatively estimated to have been at least 30 °C, but may have reached as high as 36 °C.[33] Minimum SSTs in mid-latitude oceans were >20 °C.[34] This exceptional warmth persisted until the Turonian-Coniacian boundary.[35]

One possible cause of this hothouse was sub-oceanic volcanism. During the middle of the Cretaceous period, the rate of crustal production reached a peak, which may have been related to the rifting of the newly formed Atlantic Ocean.[36] It was also caused by the widespread melting of hot mantle plumes under the ocean crust, at the base of the lithosphere, which may have resulted in the thickening of the oceanic crust in the Pacific and Indian Oceans. The resulting volcanism would have sent large quantities of carbon dioxide into the atmosphere, leading to an increase in global temperatures. Several independent events related to large igneous provinces (LIPs) occurred around the time of OAE2. A multitude of LIPs were active during OAE2: the Madagascar,[37][38] Caribbean,[39][40][41] Gorgona,[42] Ontong Java,[37] and High Arctic LIPs.[43][44][45] The abundance of LIPs at this time reflects a major overturning in mantle convection.[46] Trace metals such as chromium (Cr), scandium (Sc), copper (Cu) and cobalt (Co) have been found at the Cenomanian-Turonian boundary, which suggests that an LIP could have been one of the main basic causes involved in the contribution of the event.[47] The timing of the peak in trace metal concentration coincides with the middle of the anoxic event, suggesting that the effects of the LIPs may have occurred during the event, but may not have initiated the event. Other studies linked the lead (Pb) isotopes of OAE-2 to the Caribbean-Colombian and the Madagascar LIPs.[48] An osmium isotope excursion coeval with OAE2 strongly suggests submarine volcanism as its cause;[49] in the Pacific, an unradiogenic osmium spike began about 350 kyr before the onset of OAE2 and terminated around 240 kyr after OAE2's beginning;[50] the osmium isotope data from a highly expanded OAE2 interval in southern Tibet show multiple osmium excursions with the most pronounced one lagging the onset of OAE2 by ≈50 kyr that was probably related to the ocean connectivity change at ~94.5 Ma.[51] Osmium data also reveal that three distinct pulses of intense volcanism occurred ~60, ~270, and ~400 kyr after OAE2's onset, prolonging it.[52] Positive neodymium isotope excursions provide additional indications of pervasive volcanism as a cause of OAE2.[53] Enrichments in zinc further bolster and reinforce the existence of extensive hydrothermal volcanism,[54] as do extreme negative δ53Cr excursions.[55] The absence of geographically widespread mercury (Hg) anomalies resulting from OAE2 has been suggested to be because of the limited dispersal range of this heavy metal by submarine volcanism.[56] A modeling study performed in 2011 confirmed that it is possible that a LIP may have initiated the event, as the model revealed that the peak amount of carbon dioxide degassing from volcanic LIP degassing could have resulted in more than 90 percent global deep-ocean anoxia.[57]

Later on, when anoxia became widespread, the production of nitrous oxide, a greenhouse gas about 1,000 times more potent than carbon dioxide, drastically increased because of elevated nitrification and denitrification rates. This powerful positive feedback mechanism is what may have enabled extremely hot temperatures to persist in spite of the supercharged organic carbon burial associated with anoxic events.[58]

Plenus Cool Event

Large-scale organic carbon burial acted as a negative feedback loop that partially mitigated the warming effects of volcanic discharge of carbon dioxide, resulting in the Plenus Cool Event during the Metoicoceras geslinianum European ammonite biozone.[59] Global average temperatures fell to around 4 °C lower than they were pre-OAE2.[31] Equatorial SSTs dropped by 2.5–5.5 °C.[60] This cooling event was insufficient at completely stopping the rise in global temperatures. This negative feedback was ultimately overridden, as global temperatures continued to shoot up in sync with continued volcanic release of carbon dioxide following the Plenus Cool Event,[59] although this theory has been criticised and the warming after the Plenus Cool Event attributed to decreased silicate weathering instead.[61]

Ocean acidification

Within the oceans, the emission of SO2, H2S, CO2, and halogens would have increased the acidity of the water, causing the dissolution of carbonate, and a further release of carbon dioxide. Evidence of ocean acidification can be gleaned from δ44/40Ca increases coeval with the extinction event,[62][63][64] as well as coccolith malformation and dwarfism.[65] Ocean acidification was exacerbated by a positive feedback loop of increased heterotrophic respiration in highly biologically productive waters, elevating seawater concentrations of carbon dioxide and further decreasing pH.[66]

Anoxia and euxinia

When the volcanic activity declined, this run-away greenhouse effect would have likely been put into reverse. The increased CO2 content of the oceans could have increased organic productivity in the ocean surface waters. The consumption of this newly abundant organic life by aerobic bacteria would produce anoxia and mass extinction.[67] An acceleration of the hydrological cycle induced by warmer global temperatures drove greater fluxes of nutrient runoff into the oceans, fuelling primary productivity.[68][69] The global environmental disturbance that resulted in these conditions increased atmospheric and oceanic temperatures. Extreme hothouse conditions encouraged ocean stratification.[70] Boundary sediments show an enrichment of trace elements, and contain elevated δ13C values.[71][72] The positive δ13C excursion found at the Cenomanian-Turonian boundary is one of the main carbon isotope events of the Mesozoic. It represents one of the largest disturbances in the global carbon cycle from the past 110 million years. This δ13C excursion indicates a significant increase in the burial rate of organic carbon, indicating the widespread deposition and preservation of organic carbon-rich sediments and that the ocean was depleted of oxygen at the time.[73][74][75] Depletion of manganese in sediments corresponding to OAE2 provides additional strong evidence of severe bottom water oxygen depletion.[54] An increase in the abundance of the planktonic foraminifer Heterohelix provides further evidence still of anoxia.[76][52] The resulting elevated levels of carbon burial would account for the black shale deposition in the ocean basins.[71] The proto-North Atlantic in particular was a hotbed of carbon burial during OAE2 as it was in later, less severe anoxic events.[77]

Sulphate reduction increased during OAE2,[19] causing euxinia, a type of anoxia defined by sulphate reduction and hydrogen sulphide production, to occur during OAE2, as revealed by negative δ53Cr excursions,[78] positive δ98Mo excursions,[79] a low seawater molybdenum inventory,[80] and molecular biomarkers of green sulfur bacteria.[81][82][83]

OAE2 began on the southern margins of the proto-North Atlantic, from where anoxia spread across the rest of the proto-North Atlantic and then into the Western Interior Seaway (WIS) and the epicontinental seas of the Western Tethys.[84] Anoxic waters spread rapidly throughout the WIS due to marine transgression and a powerful cyclonic circulation resulting from an imbalance between precipitation in the north and evaporation in the south.[85] Anoxia was especially intense in the eastern North Sea, evidenced by its very positive δ13C values.[86] Thanks to persistent upwelling, some marine regions, such as the South Atlantic, were able to remain partially oxygenated at least intermittently.[87] Indeed, redox states of oceans vary geographically, bathymetrically and temporally during OAE2.[88]

Milankovitch cycles

It has been hypothesised that the Cenomanian-Turonian boundary event occurred during a period of very low variability in Earth's insolation, which has been theorised to be the result of coincident nodes in all orbital parameters. Barring chaotic perturbations in Earth's and Mars' orbits, the simultaneous occurrence of nodes of orbital eccentricity, axial precession, and obliquity on Earth occurs approximately every 2.45 million years.[89] Numerous other oceanic anoxic events occurred throughout the extremely warm greenhouse conditions of the Middle Cretaceous,[90] and it has been suggested that these Middle Cretaceous ocean anoxic events occurred cyclically in accordance with orbital cycle patterns.[89] The mid-Cenomanian Event (MCE), which occurred in the Rotalipora cushmani planktonic foraminifer biozone, has been argued to be another example supporting this hypothesis of regular oceanic anoxic events governed by Milankovitch cycles.[90] The MCE took place approximately 2.4 million years before the Cenomanian-Turonian oceanic anoxic event, roughly at the time when an anoxic event would be expected to occur given such a cycle.[89] Geochemical evidence from a sediment core in the Tarfaya Basin is indicative of the main positive carbon isotope excursion occurring during a prolonged eccentricity minimum. Carbon isotope shifts smaller in scale observed in this core likely reflected variability in obliquity.[91] Ocean Drilling Program Site 1138 in the Kerguelen Plateau yields evidence of a 20,000 to 70,000 year periodicity in changes in sedimentation, suggesting that either obliquity or precession governed the large-scale burial of organic carbon.[92] Within the OAE2 positive δ13C excursion, short eccentricity scale carbon isotope variability is documented in a significantly expanded OAE2 interval from southern Tibet;[21] periodic negative δ13C excursions paced by the short eccentricity cycle are easily detectable in southwestern Utah too.[93]

Enhanced phosphorus recycling

The phosphorus retention ability of seafloor sediments declined during OAE2,[15][94] revealed by a decline in reactive phosphorus species within OAE2 sediments.[95] The mineralisation of seafloor phosphorus into apatite was inhibited by the significantly lower pH of seawater and much warmer temperatures during the Cenomanian and Turonian compared to the present day, which meant that significantly more phosphorus was recycled back into ocean water after being deposited on the sea floor during this time. This would have intensified a positive feedback loop in which phosphorus is recycled faster into anoxic seawater compared to oxygen-rich water, which in turn fertilises the water, causes increased eutrophication, and further depletes the seawater of oxygen.[16] The influx of volcanically erupted and chemically weathered sulphate into the ocean also inhibited phosphorus burial by increasing hydrogen sulphide production,[96] which hinders the burial of phosphorus through sorption to iron oxyhydroxide phases.[18] OAE2 may have occurred during a peak in a 5-6 Myr cycle governing phosphorus availability; at this and other peaks in this oscillation, an increase in chemical weathering would have increased the marine phosphorus inventory and sparked a positive feedback loop of increasing productivity, anoxia, and phosphorus recycling that was only ended by a negative feedback of increased atmospheric oxygenation and wildfire activity that decreased chemical weathering, a feedback which operated on a much longer timescale.[17] Enhanced phosphorus recycling would have resulted in an abundance of nitrogen fixing bacteria, increasing the availability of yet another limiting nutrient and supercharging primary productivity through nitrogen fixation.[97] The ratio of bioavailable nitrogen to bioavailable phosphorus, which is 16:1 in the present, fell precipitously as the ocean transitioned from being oxic and nitrate-dominated to anoxic and ammonium-dominated.[58] A potent feedback loop of nitrogen fixation, productivity, deoxygenation, nitrogen removal, and phosphorus recycling was created.[13] Bacterial hopanoids indicate populations of nitrogen fixing cyanobacteria were high during OAE2, providing a rich supply of nitrates and nitrites.[98] Negative δ15N values reveal the dominance of ammonium through regenerative nutrient loops in the proto-North Atlantic.[99]

Decreased sulphide oxidation

In the present day, sulphidic waters are generally prevented from spreading throughout the water column by the oxidation of sulphide with nitrate. However, during OAE2, the inventory of seawater nitrate was lower, meaning that chemolithoautotrophic oxidation of sulphides with nitrates was inefficient at preventing the spread of euxinia.[100]

Sea level rise

A marine transgression in the latest Cenomanian resulted in an increase in average water depth, causing seawater to become less eutrophic in shallow, epicontinental seas. Turnovers in marine biota in such epicontinental seas have been suggested to be driven more so by changes in water depth rather than anoxia.[101] Sea level rise also contributed to anoxia by transporting terrestrial plant matter from inundated lands seaward, providing an abundant source of sustenance for eutrophicating microorganisms.[102]

Geological effects

Phosphate deposition

A phosphogenic event occurred in the Bohemian Cretaceous Basin during the peak of oceanic anoxia. Phosphorus liberation in the pore water environment, several centimetres below the interface between seafloor sediments and the water column, enabled the precipitation of phosphate through biological mediation by microorganisms.[103]

Increase in weathering

Strontium and calcium isotope ratios both indicate that silicate weathering increased over the course of OAE2. Because of its effectiveness as a carbon sink on geologic timescales, the uptick in sequestration of carbon dioxide by the lithosphere may have helped to stabilise global temperatures after global temperatures soared.[104] Particularly so at high latitudes, where the increase in weatherability was very pronounced.[105]

Biotic effects

Changes in oceanic biodiversity and its implications

The event brought about the extinction of the pliosaurs, and most ichthyosaurs. Coracoids of Maastrichtian age were once interpreted by some authors as belonging to ichthyosaurs, but these have since been interpreted as plesiosaur elements instead.[106]

Although the cause is still uncertain, the result starved the Earth's oceans of oxygen for nearly half a million years, causing the extinction of approximately 27 percent of marine invertebrates, including certain planktic and benthic foraminifera, mollusks, bivalves, dinoflagellates and calcareous nannofossils.[67] Planktonic foraminifera that dwelt in deeper waters were especially hard hit by the expansion of oxygen minimum zones.[107] In Whadi El Ghaib, a site in Sinai, Egypt, the foraminiferal community during OAE2 was low in diversity and dominated by taxa that were extremely tolerant of low salinity, anoxic water.[108] In the southeastern Indian Ocean, off the coast of Australia, the planktonic foraminifer Microhedbergella was highly abundant,[109] while Heterohelix thrived in reducing waters in the South Atlantic.[76][52] The alterations in diversity of various marine invertebrate species such as calcareous nannofossils are reflective and characteristic of oligotrophy and ocean warmth in an environment with short spikes of productivity followed by long periods of low fertility.[110] A study performed in the Cenomanian-Turonian boundary of Wunstorf, Germany, reveal the uncharacteristic dominance of a calcareous nannofossil species, Watznaueria, present during the event. Unlike the Biscutum species, which prefer mesotrophic conditions and were generally the dominant species before and after the C/T boundary event; Watznaueria species prefer warm, oligotrophic conditions.[111] In the Ohaba-Ponor section in Romania, the presence of Watznaueria barnesae indicates warm conditions, while the abundances of Biscutum constans, Zeugrhabdotus erectus, and Eprolithus floralis peak during cool intervals.[110] Sites in Colorado, England , France , and Sicily show an inverse relationship between atmospheric carbon dioxide levels and the size of calcareous nannoplankton.[112] Radiolarians also suffered heavy losses in OAE2, one of their highest diversity losses in the Cretaceous.[113] Rudist bivalves suffered high extinction rates combined with low origination rates during OAE2.[114]

The diversity of trace fossils sharply plummeted during the beginning of the Cenomanian-Turonian boundary event. The recovery interval after the anoxic event's conclusion features an abundance of Planolites and is characterised overall by a high degree of bioturbation.[115]

At the time, there were also peak abundances of the green algal groups Botryococcus and prasinophytes, coincident with pelagic sedimentation. The abundances of these algal groups are strongly related to the increase of both the oxygen deficiency in the water column and the total content of organic carbon. The evidence from these algal groups suggest that there were episodes of halocline stratification of the water column during the time. A species of freshwater dinocyst—Bosedinia—was also found in the rocks dated to the time and these suggest that the oceans had reduced salinity.[116][117]

Changes in terrestrial biodiversity

No major change in terrestrial ecosystems is known to have been synchronous with the marine transgression associated with OAE2, although the loss of freshwater floodplain habitat has been speculated to have possibly resulted in the demise of some freshwater taxa. In fossiliferous rocks in southwestern Utah, a local extirpation of some metatherians and brackish water vertebrates is associated with the later marine regression following OAE2 in the Turonian. Whatever the nature and magnitude of terrestrial extinctions at or near the Cenomanian-Turonian boundary was, it was most likely caused mainly by other factors than eustatic sea level fluctuations.[118] The effect of the ecological crisis on terrestrial plants has been concluded to have been inconsequential, in contrast to extinction events driven by terrestrial large igneous provinces.[119]

See also

References

  1. "International Chronostratigraphic Chart". https://stratigraphy.org/ICSchart/ChronostratChart2021-10.jpg. 
  2. Cetean, Claudia G.; Balc, Ramona; Kaminski, Michael A.; Filipescu, Sorin (August 2008). "Biostratigraphy of the Cenomanian-Turonian boundary in the Eastern Carpathians (Dâmboviţa Valley): preliminary observations". Studia Universitatis Babeş-Bolyai, Geologia 53 (1): 11–23. doi:10.5038/1937-8602.53.1.2. http://discovery.ucl.ac.uk/18643/. 
  3. Li, Yong-Xiang; Bralower, Timothy J.; Montañez, Isabel P.; Osleger, David A.; Arthur, Michael A.; Bice, David M.; Herbert, Timothy D.; Erba, Elisabetta et al. (15 July 2008). "Toward an orbital chronology for the early Aptian Oceanic Anoxic Event (OAE1a, ≈120 Ma)". Earth and Planetary Science Letters 271 (1–4): 88–100. doi:10.1016/j.epsl.2008.03.055. Bibcode2008E&PSL.271...88L. https://pennstate.pure.elsevier.com/en/publications/toward-an-orbital-chronology-for-the-early-aptian-oceanic-anoxic-. Retrieved 17 March 2023. 
  4. Petrizzo, Maria Rose; Amaglio, Giulia; Watkins, David K.; MacLeod, Kenneth G.; Huber, Brian T.; Hasegawa, Takashi; Wolfgring, Erik (19 August 2022). "Biotic and Paleoceanographic Changes Across the Late Cretaceous Oceanic Anoxic Event 2 in the Southern High Latitudes (IODP Sites U1513 and U1516, SE Indian Ocean)". Paleoceanography and Paleoclimatology 37 (9): e2022PA004474. doi:10.1029/2022PA004474. PMID 36247808. Bibcode2022PaPa...37.4474P. 
  5. Selby, David; Mutterlose, Jörg; Condon, Daniel J. (July 2009). "U–Pb and Re–Os geochronology of the Aptian/Albian and Cenomanian/Turonian stage boundaries: Implications for timescale calibration, osmium isotope seawater composition and Re–Os systematics in organic-rich sediments". Chemical Geology 265 (3–4): 394–409. doi:10.1016/j.chemgeo.2009.05.005. Bibcode2009ChGeo.265..394S. http://nora.nerc.ac.uk/id/eprint/7741/. Retrieved 17 March 2023. 
  6. Leckie, R; Bralower, T.; Cashman, R. (2002). "Oceanic anoxic events and plankton evolution: Biotic response to tectonic forcing during the mid-Cretaceous". Paleoceanography and Paleoclimatology 17 (3): 1–29. doi:10.1029/2001pa000623. Bibcode2002PalOc..17.1041L. https://www.geo.umass.edu/faculty/leckie/Leckie%20et%20al.%202002.pdf. 
  7. Meyers, Stephen R.; Siewert, Sarah E.; Singer, Brad S.; Sageman, Bradley B.; Condon, Daniel J.; Obradovich, John D.; Jicha, Brian R.; Sawyer, David A. (January 2012). "Intercalibration of radioisotopic and astrochronologic time scales for the Cenomanian-Turonian boundary interval, Western Interior Basin, USA". Geology 40 (1): 7–10. doi:10.1130/g32261.1. ISSN 1943-2682. Bibcode2012Geo....40....7M. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/40/1/7/130721/Intercalibration-of-radioisotopic-and?redirectedFrom=fulltext. Retrieved 2 April 2023. 
  8. Paul, C. R. C.; Lamolda, M. A.; Mitchell, S. F.; Vaziri, M. R.; Gorostidi, A.; Marshall, J. D. (15 June 1999). "The Cenomanian–Turonian boundary at Eastbourne (Sussex, UK): a proposed European reference section". Palaeogeography, Palaeoclimatology, Palaeoecology 150 (1–2): 83–121. doi:10.1016/S0031-0182(99)00009-7. Bibcode1999PPP...150...83P. https://www.sciencedirect.com/science/article/abs/pii/S0031018299000097. Retrieved 28 January 2023. 
  9. Arthur, Michael A.; Dean, Walter E.; Pratt, Lisa M. (20 October 1988). "Geochemical and climatic effects of increased marine organic carbon burial at the Cenomanian/Turonian boundary". Nature 335 (6192): 714–717. doi:10.1038/335714a0. Bibcode1988Natur.335..714A. https://www.nature.com/articles/335714a0. Retrieved 28 January 2023. 
  10. Jarvis, Ian; Gale, Andrew S.; Jenkyns, Hugh C.; Pearce, Martin A. (3 July 2006). "Secular variation in Late Cretaceous carbon isotopes: a new δ13C carbonate reference curve for the Cenomanian–Campanian (99.6–70.6 Ma)". Geological Magazine 143 (5): 561–608. doi:10.1017/S0016756806002421. Bibcode2006GeoM..143..561J. https://www.cambridge.org/core/journals/geological-magazine/article/abs/secular-variation-in-late-cretaceous-carbon-isotopes-a-new-13c-carbonate-reference-curve-for-the-cenomaniancampanian-996706-ma/CA45840104D8CDFF05652AF85F5FC888. Retrieved 18 March 2023. 
  11. Grosheny, Danièle; Beaudoin, Bernard; Morel, Laurence; Desmares, Delphine (October 2006). "High-resolution biotratigraphy and chemostratigraphy of the Cenomanian/Turonian boundary event in the Vocontian Basin, southeast France". Cretaceous Research 27 (5): 629–640. doi:10.1016/j.cretres.2006.03.005. Bibcode2006CrRes..27..629G. https://www.sciencedirect.com/science/article/abs/pii/S0195667106000383. Retrieved 11 April 2023. 
  12. Jarvis, Ian; Carson, G. A.; Cooper, M. K. E.; Hart, M. B.; Leary, P. N.; Tocher, B. A.; Horne, D.; Rosenfeld, A. (March 1988). "Microfossil Assemblages and the Cenomanian-Turonian (late Cretaceous) Oceanic Anoxic Event". Cretaceous Research 9 (1): 3–103. doi:10.1016/0195-6671(88)90003-1. Bibcode1988CrRes...9....3J. https://www.sciencedirect.com/science/article/abs/pii/0195667188900031. Retrieved 27 April 2023. 
  13. 13.0 13.1 Junium, Christopher K.; Arthur, Michael A. (3 March 2007). "Nitrogen cycling during the Cretaceous, Cenomanian-Turonian Oceanic Anoxic Event II". Geochemistry, Geophysics, Geosystems 8 (3): 1–18. doi:10.1029/2006GC001328. Bibcode2007GGG.....8.3002J. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2006GC001328. Retrieved 25 April 2023. 
  14. Peryt, D.; Wyrwicka, K. (September 1993). "The Cenomanian/Turonian boundary event in Central Poland". Palaeogeography, Palaeoclimatology, Palaeoecology 104 (1–4): 185–197. doi:10.1016/0031-0182(93)90130-B. Bibcode1993PPP...104..185P. https://www.sciencedirect.com/science/article/abs/pii/003101829390130B. Retrieved 28 January 2023. 
  15. 15.0 15.1 Mort, Haydon P.; Adatte, Thierry; Föllmi, Karl B.; Keller, Gerta; Steinmann, Philipp; Matera, Virginie; Berner, Zsolt; Stüben, Doris (1 June 2007). "Phosphorus and the roles of productivity and nutrient recycling during oceanic anoxic event 2". Geology 35 (6): 483–486. doi:10.1130/G23475A.1. Bibcode2007Geo....35..483M. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/35/6/483/129857/Phosphorus-and-the-roles-of-productivity-and. Retrieved 11 April 2023. 
  16. 16.0 16.1 Papadomanolaki, Nina M.; Lenstra, Wytze K.; Wolthers, Mariette; Slomp, Caroline P. (1 July 2022). "Enhanced phosphorus recycling during past oceanic anoxia amplified by low rates of apatite authigenesis". Science Advances 8 (26): eabn2370. doi:10.1126/sciadv.abn2370. PMID 35776794. Bibcode2022SciA....8N2370P. 
  17. 17.0 17.1 Handoh, Itsuki C.; Lenton, Timothy M. (8 October 2003). "Periodic mid-Cretaceous oceanic anoxic events linked by oscillations of the phosphorus and oxygen biogeochemical cycles". Global Biogeochemical Cycles 17 (4): 3-1-3-11. doi:10.1029/2003GB002039. Bibcode2003GBioC..17.1092H. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2003GB002039. Retrieved 14 June 2023. 
  18. 18.0 18.1 Gomes, Maya L.; Hurtgen, Matthew T.; Sageman, Bradley B. (21 December 2015). "Biogeochemical sulfur cycling during Cretaceous oceanic anoxic events: A comparison of OAE1a and OAE2". Paleoceanography and Paleoclimatology 31 (2): 233–251. doi:10.1002/2015PA002869. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015PA002869. Retrieved 19 December 2022. 
  19. 19.0 19.1 Okhouchi, N.; Kawamura, K.; Kajiwara, Y.; Wada, E.; Okada, M.; Kanamatsu, T.; Taira, A. (1 June 1999). "Sulfur isotope records around Livello Bonarelli (northern Apennines, Italy) black shale at the Cenomanian-Turonian boundary". Geology 27 (6): 535–538. doi:10.1130/0091-7613(1999)027<0535:SIRALB>2.3.CO;2. Bibcode1999Geo....27..535O. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/27/6/535/207117/Sulfur-isotope-records-around-Livello-Bonarelli. Retrieved 19 December 2022. 
  20. Sageman, Bradley B.; Meyers, Stephen R.; Arthur, Michael A. (1 February 2006). "Orbital time scale and new C-isotope record for Cenomanian-Turonian boundary stratotype". Geology 34 (2): 125. doi:10.1130/G22074.1. Bibcode2006Geo....34..125S. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/34/2/125/129449/Orbital-time-scale-and-new-C-isotope-record-for?redirectedFrom=fulltext. Retrieved 17 March 2023. 
  21. 21.0 21.1 21.2 Li, Yong-Xiang; Montañez, Isabel P.; Liu, Zhonghui; Ma, Lifeng (March 2017). "Astronomical constraints on global carbon-cycle perturbation during Oceanic Anoxic Event 2 (OAE2)". Earth and Planetary Science Letters 462: 35–46. doi:10.1016/j.epsl.2017.01.007. ISSN 0012-821X. Bibcode2017E&PSL.462...35L. https://www.sciencedirect.com/science/article/abs/pii/S0012821X17300134. Retrieved 17 March 2023. 
  22. G. Bonarelli, Il territorio di Gubbio - Notizie geologiche, Roma 1891
  23. G. Parisi, F. Piergiovanni e M. Marcucci, Il livello Bonarelli nell'area umbro-marchigiana, in Stratigrafia del Mesozoico e Cenozoico nell'area Umbro-Marchigiana, Roma, 1989
  24. Bryant, Raquel; Belanger, Christina L. (19 January 2023). "Spatial heterogeneity in benthic foraminiferal assemblages tracks regional impacts of paleoenvironmental change across Cretaceous OAE2". Paleobiology 49 (3): 431–453. doi:10.1017/pab.2022.47. 
  25. Eldrett, James S.; Ma, Chao; Bergman, Steven C.; Lutz, Brendan; Gregory, F. John; Dodsworth, Paul; Phipps, Mark; Hardas, Petros et al. (September–December 2015). "An astronomically calibrated stratigraphy of the Cenomanian, Turonian and earliest Coniacian from the Cretaceous Western Interior Seaway, USA: Implications for global chronostratigraphy". Cretaceous Research 56: 316–344. doi:10.1016/j.cretres.2015.04.010. Bibcode2015CrRes..56..316E. https://www.sciencedirect.com/science/article/abs/pii/S0195667115000622. Retrieved 13 June 2023. 
  26. Xu, Kang; Zhong, Yi; Tsikos, H.; Chen, Hongjin; Li, Yawei (16 December 2023). "Orbital-paced Oceanic Anoxic Event 2 evolution and astrochronology in the Mentelle Basin (Australia) at southern high latitudes" (in en). Palaeogeography, Palaeoclimatology, Palaeoecology: 111973. doi:10.1016/j.palaeo.2023.111973. https://linkinghub.elsevier.com/retrieve/pii/S0031018223005916. Retrieved 30 December 2023. 
  27. Coccioni, Rodolfo; Luciani, Valeria (1 April 2004). "Planktonic foraminifera and environmental changes across the Bonarelli Event (OAE2, latest Cenomanian) in its type area: A high-resolution study from the tethyan reference Bottaccione section (Gubbio, Central Italy)". Journal of Foraminiferal Research 34 (2): 109–129. doi:10.2113/0340109. https://www.researchgate.net/publication/250084952. Retrieved 30 December 2022. 
  28. Bottini, Cinzia; Erba, Elisabetta (10 August 2018). "Mid-Cretaceous paleoenvironmental changes in the western Tethys". Climate of the Past 14 (8): 1147–1163. doi:10.5194/cp-14-1147-2018. Bibcode2018CliPa..14.1147B. https://cp.copernicus.org/articles/14/1147/2018/cp-14-1147-2018-discussion.html. Retrieved 14 June 2023. 
  29. Scotese, Christopher Robert; Song, Haijun; Mills, Benjamin J. W.; Van der Meer, Douwe G. (April 2021). "Phanerozoic paleotemperatures: The earth's changing climate during the last 540 million years". Earth-Science Reviews 215: 103503. doi:10.1016/j.earscirev.2021.103503. Bibcode2021ESRv..21503503S. https://www.sciencedirect.com/science/article/abs/pii/S0012825221000027#:~:text=The%20history%20of%20global%20changes,and%20cooling%20episodes%20(chronotemps).. Retrieved 10 June 2023. 
  30. Hong, Sung Kyung; Lee, Yong Il (15 April 2012). "Evaluation of atmospheric carbon dioxide concentrations during the Cretaceous". Earth and Planetary Science Letters 327-328: 23–28. doi:10.1016/j.epsl.2012.01.014. Bibcode2012E&PSL.327...23H. https://www.sciencedirect.com/science/article/abs/pii/S0012821X12000246. Retrieved 13 June 2023. 
  31. 31.0 31.1 Forster, Astrid; Schouten, Stephan; Moriya, Kazuyoshi; Wilson, Paul A.; Sinninghe Damsté, Jaap S. (14 March 2007). "Tropical warming and intermittent cooling during the Cenomanian/Turonian oceanic anoxic event 2: Sea surface temperature records from the equatorial Atlantic". Paleoceanography and Paleoclimatology 22 (1): 1–14. doi:10.1029/2006PA001349. Bibcode2007PalOc..22.1219F. 
  32. Voigt, Silke; Gale, Andrew S.; Flögel, Sascha (8 December 2004). "Midlatitude shelf seas in the Cenomanian-Turonian greenhouse world: Temperature evolution and North Atlantic circulation: CENOMANIAN-TURONIAN TEMPERATURE EVOLUTION" (in en). Paleoceanography and Paleoclimatology 19 (4): 1–17. doi:10.1029/2004PA001015. http://doi.wiley.com/10.1029/2004PA001015. Retrieved 4 September 2023. 
  33. Wilson, Paul A.; Norris, Richard D.; Cooper, Matthew J. (1 July 2002). "Testing the Cretaceous greenhouse hypothesis using glassy foraminiferal calcite from the core of the Turonian tropics on Demerara Rise". Geology 30 (7): 607–610. doi:10.1130/0091-7613(2002)030<0607:TTCGHU>2.0.CO;2. Bibcode2002Geo....30..607W. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/30/7/607/191749/Testing-the-Cretaceous-greenhouse-hypothesis-using?redirectedFrom=fulltext. Retrieved 5 April 2023. 
  34. O'Brien, Charlotte L.; Robinson, Stuart A.; Pancost, Richard D.; Sinninghe Damsté, Jaap S.; Schouten, Stefan; Lunt, Daniel J.; Alsenz, Heiko; Bornemann, André et al. (September 2017). "Cretaceous sea-surface temperature evolution: Constraints from TEX86 and planktonic foraminiferal oxygen isotopes". Earth-Science Reviews 172: 224–247. doi:10.1016/j.earscirev.2017.07.012. Bibcode2017ESRv..172..224O. 
  35. Forster, Astrid; Schouten, Stefan; Baas, Marianne; Sinninghe Damsté, Jaap S. (1 October 2007). "Mid-Cretaceous (Albian–Santonian) sea surface temperature record of the tropical Atlantic Ocean" (in en). Geology 35 (10): 919–922. doi:10.1130/G23874A.1. ISSN 0091-7613. https://pubs.geoscienceworld.org/geology/article/35/10/919-922/129719. Retrieved 4 September 2023. 
  36. Poulsen, Christopher J.; Gendaszek, Andrew S.; Jacob, Robert L. (1 February 2003). "Did the rifting of the Atlantic Ocean cause the Cretaceous thermal maximum?". Geology 31 (2): 115–118. doi:10.1130/0091-7613(2003)031<0115:DTROTA>2.0.CO;2. Bibcode2003Geo....31..115P. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/31/2/115/192533/Did-the-rifting-of-the-Atlantic-Ocean-cause-the. Retrieved 17 March 2023. 
  37. 37.0 37.1 Scaife, J. D.; Ruhl, Micha; Dickson, A. J.; Mather, Tamsin A.; Jenkyns, Hugh C.; Percival, L. M. E.; Hesselbo, Stephen P.; Cartwright, J. et al. (1 November 2017). "Sedimentary Mercury Enrichments as a Marker for Submarine Large Igneous Province Volcanism? Evidence From the Mid-Cenomanian Event and Oceanic Anoxic Event 2 (Late Cretaceous)". Geochemistry, Geophysics, Geosystems 18 (12): 4253–4275. doi:10.1002/2017GC007153. Bibcode2017GGG....18.4253S. 
  38. Sinton, C. W.; Duncan, R. A. (1 December 1997). "Potential links between ocean plateau volcanism and global ocean anoxia at the Cenomanian-Turonian boundary" (in en). Economic Geology 92 (7–8): 836–842. doi:10.2113/gsecongeo.92.7-8.836. ISSN 1554-0774. http://pubs.geoscienceworld.org/economicgeology/article/92/7-8/836/21768/Potential-links-between-ocean-plateau-volcanism. Retrieved 25 September 2023. 
  39. Serrano, Lina; Ferrari, Luca; López Martínez, Margarita; Petrone, Chiara Maria; Jaramillo, Carlos (15 September 2011). "An integrative geologic, geochronologic and geochemical study of Gorgona Island, Colombia: Implications for the formation of the Caribbean Large Igneous Province". Earth and Planetary Science Letters 309 (3–4): 324–336. doi:10.1016/j.epsl.2011.07.011. Bibcode2011E&PSL.309..324S. https://www.sciencedirect.com/science/article/abs/pii/S0012821X11004262. Retrieved 22 April 2023. 
  40. Du Vivier, Alice D. C.; Selby, David; Sageman, Bradley B.; Jarvis, Ian; Gröcke, Darren R.; Voigt, Silke (1 March 2014). "Marine 187Os/188Os isotope stratigraphy reveals the interaction of volcanism and ocean circulation during Oceanic Anoxic Event 2". Earth and Planetary Science Letters 389: 23–33. doi:10.1016/j.epsl.2013.12.024. ISSN 0012-821X. 
  41. Joo, Young Ji; Sageman, Bradley B.; Hurtgen, Matthew T. (1 April 2020). "Data-model comparison reveals key environmental changes leading to Cenomanian-Turonian Oceanic Anoxic Event 2". Earth-Science Reviews 203: 103123. doi:10.1016/j.earscirev.2020.103123. ISSN 0012-8252. 
  42. Kerr, Andrew C.; Tarney, John (1 April 2005). "Tectonic evolution of the Caribbean and northwestern South America: The case for accretion of two Late Cretaceous oceanic plateaus". Geology 33 (4): 269–272. doi:10.1130/G21109.1. Bibcode2005Geo....33..269K. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/33/4/269/29564/Tectonic-evolution-of-the-Caribbean-and. Retrieved 8 April 2023. 
  43. Naber, T.V.; Grasby, S.E.; Cuthbertson, J.P.; Rayner, N.; Tegner, C. (16 December 2020). "New constraints on the age, geochemistry, and environmental impact of High Arctic Large Igneous Province magmatism: Tracing the extension of the Alpha Ridge onto Ellesmere Island, Canada" (in en). Geological Society of America Bulletin 133 (7–8): 1695–1711. doi:10.1130/B35792.1. ISSN 0016-7606. 
  44. Davis, William J.; Schröder-Adams, Claudia J.; Galloway, Jennifer M.; Herrle, Jens O.; Pugh, Adam T. (24 June 2016). "U–Pb geochronology of bentonites from the Upper Cretaceous Kanguk Formation, Sverdrup Basin, Arctic Canada: constraints on sedimentation rates, biostratigraphic correlations and the late magmatic history of the High Arctic Large Igneous Province" (in en). Geological Magazine 154 (4): 757–776. doi:10.1017/S0016756816000376. ISSN 0016-7568. https://www.cambridge.org/core/journals/geological-magazine/article/abs/upb-geochronology-of-bentonites-from-the-upper-cretaceous-kanguk-formation-sverdrup-basin-arctic-canada-constraints-on-sedimentation-rates-biostratigraphic-correlations-and-the-late-magmatic-history-of-the-high-arctic-large-igneous-province/8244FCB0AE74E7E6E1E967F6E07FD178. Retrieved 14 September 2023. 
  45. Schröder-Adams, Claudia J.; Herrle, Jens O.; Selby, David; Quesnel, Alex; Froude, Gregory (1 April 2019). "Influence of the High Arctic Igneous Province on the Cenomanian/Turonian boundary interval, Sverdrup Basin, High Canadian Arctic". Earth and Planetary Science Letters 511: 76–88. doi:10.1016/j.epsl.2019.01.023. Bibcode2019E&PSL.511...76S. https://www.sciencedirect.com/science/article/abs/pii/S0012821X19300494. Retrieved 22 April 2023. 
  46. Maher, Jr., Harmon D. (January 2001). "Manifestations of the Cretaceous High Arctic Large Igneous Province in Svalbard" (in en). The Journal of Geology 109 (1): 91–104. doi:10.1086/317960. ISSN 0022-1376. https://www.journals.uchicago.edu/doi/10.1086/317960. Retrieved 16 September 2023. 
  47. Ernst, Richard E.; Youbi, Nasrrddine (July 2017). "How Large Igneous Provinces affect global climate, sometimes cause mass extinctions, and represent natural markers in the geological record". Palaeogeography, Palaeoclimatology, Palaeoecology 478: 30–52. doi:10.1016/j.palaeo.2017.03.014. Bibcode2017PPP...478...30E. https://www.sciencedirect.com/science/article/abs/pii/S0031018217302857. Retrieved 2 April 2023. 
  48. Kuroda, J.; Ogawa, N.; Tanimizu, M.; Coffin, M.; Tokuyama, H.; Kitazato, H.; Ohkouchi, N. (15 April 2007). "Contemporaneous massive subaerial volcanism and late cretaceous Oceanic Anoxic Event 2". Earth and Planetary Science Letters 256 (1–2): 211–223. doi:10.1016/j.epsl.2007.01.027. ISSN 0012-821X. Bibcode2007E&PSL.256..211K. https://www.researchgate.net/publication/222125939. Retrieved 28 March 2023. 
  49. Matsumoto, Hironao; Coccioni, Rodolfo; Frontalini, Fabrizio; Shirai, Kotaro; Jovane, Luigi; Trindade, Ricardo; Savian, Jairo F.; Koroda, Junichiro (11 January 2022). "Mid-Cretaceous marine Os isotope evidence for heterogeneous cause of oceanic anoxic events". Nature Communications 13 (1): 239. doi:10.1038/s41467-021-27817-0. PMID 35017487. Bibcode2022NatCo..13..239M. 
  50. Du Vivier, A. D. C.; Selby, David; Condon, Daniel J.; Takashima, R.; Nishi, H. (15 October 2015). "Pacific 187Os/188Os isotope chemistry and U–Pb geochronology: Synchroneity of global Os isotope change across OAE 2". Earth and Planetary Science Letters 428: 204–216. doi:10.1016/j.epsl.2015.07.020. Bibcode2015E&PSL.428..204D. 
  51. Li, Yong-Xiang; Liu, Xinyu; Selby, David; Liu, Zhonghui; Montañez, Isabel P.; Li, Xianghui (15 January 2022). "Enhanced ocean connectivity and volcanism instigated global onset of Cretaceous Oceanic Anoxic Event 2 (OAE2) ∼94.5 million years ago" (in en). Earth and Planetary Science Letters 578: 117331. doi:10.1016/j.epsl.2021.117331. https://linkinghub.elsevier.com/retrieve/pii/S0012821X21005872. Retrieved 4 September 2023. 
  52. 52.0 52.1 52.2 Sullivan, Daniel L.; Brandon, Alan D.; Eldrett, James; Bergman, Steven C.; Wright, Shawn; Minisini, Daniel (15 September 2020). "High resolution osmium data record three distinct pulses of magmatic activity during cretaceous Oceanic Anoxic Event 2 (OAE-2)" (in en). Geochimica et Cosmochimica Acta 285: 257–273. doi:10.1016/j.gca.2020.04.002. https://linkinghub.elsevier.com/retrieve/pii/S0016703720302271. Retrieved 30 December 2023. 
  53. Zheng, Xin-Yuan; Jenkyns, Hugh C.; Gale, Andrew S.; Ward, David J.; Henderson, Gideon M. (1 February 2016). "A climatic control on reorganization of ocean circulation during the mid-Cenomanian event and Cenomanian-Turonian oceanic anoxic event (OAE 2): Nd isotope evidence". Geology 44 (2): 151–154. doi:10.1130/G37354.1. Bibcode2016Geo....44..151Z. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/44/2/151/132055/A-climatic-control-on-reorganization-of-ocean?redirectedFrom=fulltext. Retrieved 14 June 2023. 
  54. 54.0 54.1 Turgeon, Steven; Brumsack, Hans-Jürgen (15 November 2006). "Anoxic vs dysoxic events reflected in sediment geochemistry during the Cenomanian–Turonian Boundary Event (Cretaceous) in the Umbria–Marche Basin of central Italy". Chemical Geology 234 (3–4): 321–339. doi:10.1016/j.chemgeo.2006.05.008. Bibcode2006ChGeo.234..321T. https://www.sciencedirect.com/science/article/abs/pii/S0009254106002713. Retrieved 14 June 2023. 
  55. Holmden, C.; Jacobson, A. D.; Sageman, B. B.; Hurtgen, M. T. (1 August 2016). "Response of the Cr isotope proxy to Cretaceous Ocean Anoxic Event 2 in a pelagic carbonate succession from the Western Interior Seaway". Geochimica et Cosmochimica Acta 186: 277–295. doi:10.1016/j.gca.2016.04.039. ISSN 0016-7037. https://www.sciencedirect.com/science/article/pii/S0016703716302083. Retrieved 25 September 2023. 
  56. Percival, Lawrence M. E.; Jenkyns, Hugh C.; Mather, Tamsin A.; Dickson, Alexander J.; Batenburg, Sietske J.; Ruhl, Micha; Hesselbo, Stephen B.; Barclay, Richard et al. (October 2018). "Does large igneous province volcanism always perturb the mercury cycle? Comparing the records of Oceanic Anoxic Event 2 and the end-Cretaceous to other Mesozoic events". American Journal of Science 318 (8): 799–860. doi:10.2475/08.2018.01. Bibcode2018AmJS..318..799P. https://www.ajsonline.org/content/318/8/799. Retrieved 28 March 2023. 
  57. Flögel, S.; Wallmann, K.; Poulsen, C. J.; Zhou, J.; Oschlies, A.; Voigt, S.; Kuhnt, W. (May 2011). "Simulating the biogeochemical effects of volcanic CO2 degassing on the oxygen-state of the deep ocean during the Cenomanian/Turonian Anoxic Event (OAE2)". Earth and Planetary Science Letters 305 (3–4): 371–384. doi:10.1016/j.epsl.2011.03.018. ISSN 0012-821X. Bibcode2011E&PSL.305..371F. https://www.researchgate.net/publication/230584254. Retrieved 2 April 2023. 
  58. 58.0 58.1 Naafs, B. David A.; Monteiro, Fanny M.; Pearson, Ann; Higgins, Meytal B.; Pancost, Richard D.; Ridgwell, Andy (10 December 2019). "Fundamentally different global marine nitrogen cycling in response to severe ocean deoxygenation". Proceedings of the National Academy of Sciences of the United States of America 116 (50): 24979–24984. doi:10.1073/pnas.1905553116. PMID 31767742. Bibcode2019PNAS..11624979N. 
  59. 59.0 59.1 Jarvis, Ian; Lignum, John S.; Gröcke, Darren R.; Jenkyns, Hugh C.; Pearce, Martin A. (19 July 2011). "Black shale deposition, atmospheric CO2 drawdown, and cooling during the Cenomanian-Turonian Oceanic Anoxic Event". Paleoceanography and Paleoclimatology 26 (3): 1–17. doi:10.1029/2010PA002081. Bibcode2011PalOc..26.3201J. 
  60. Sinninghe Damsté, Jaap S.; Van Bentum, Elisabeth C.; Reichart, Gert-Jan; Pross, Jörg; Schouten, Stefan (15 April 2010). "A CO2 decrease-driven cooling and increased latitudinal temperature gradient during the mid-Cretaceous Oceanic Anoxic Event 2". Earth and Planetary Science Letters 293 (1–2): 97–103. doi:10.1016/j.epsl.2010.02.027. Bibcode2010E&PSL.293...97S. https://www.sciencedirect.com/science/article/abs/pii/S0012821X10001299. Retrieved 13 June 2023. 
  61. Percival, Lawrence M. E.; Van Helmond, N. A. G. M.; Selby, David; Goderis, S.; Claeys, P. (26 September 2020). "Complex Interactions Between Large Igneous Province Emplacement and Global-Temperature Changes During the Cenomanian-Turonian Oceanic Anoxic Event (OAE 2)". Paleoceanography and Paleoclimatology 35 (10). doi:10.1029/2020PA004016. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020PA004016. Retrieved 13 June 2023. 
  62. Du Vivier, Alice D. C.; Jacobson, Andrew D.; Lehn, Gregory O.; Selby, David; Hurtgen, Matthew T.; Sageman, Bradley B. (15 April 2015). "Ca isotope stratigraphy across the Cenomanian–Turonian OAE 2: Links between volcanism, seawater geochemistry, and the carbonate fractionation factor". Earth and Planetary Science Letters 416: 121–131. doi:10.1016/j.epsl.2015.02.001. Bibcode2015E&PSL.416..121D. 
  63. Fantle, Matthew S.; Ridgwell, Andy (5 August 2020). "Towards an understanding of the Ca isotopic signal related to ocean acidification and alkalinity overshoots in the rock record". Chemical Geology 547: 119672. doi:10.1016/j.chemgeo.2020.119672. Bibcode2020ChGeo.54719672F. https://www.sciencedirect.com/science/article/abs/pii/S0009254120302114. Retrieved 23 April 2023. 
  64. Kitch, Gabriella Dawn (December 2021). "Calcium isotope ratios of malformed foraminifera reveal biocalcification stress preceded OAE2". Identifying and Constraining Biocalcification Stress from Geologic Ocean Acidification Events (PhD). Northwestern University. ProQuest 2617262217. Retrieved 4 September 2023.
  65. Hönisch, Bärbel; Ridgwell, Andy; Schmidt, Daniela N.; Thomas, Ellen; Gibbs, Samantha J.; Sluijs, Appy; Zeebe, Richard; Kump, Lee et al. (2 March 2012). "The Geological Record of Ocean Acidification". Science 335 (6072): 1058–1063. doi:10.1126/science.1208277. PMID 22383840. Bibcode2012Sci...335.1058H. https://www.science.org/doi/abs/10.1126/science.1208277. Retrieved 28 June 2023. 
  66. Jones, Matthew M.; Sageman, Bradley B.; Selby, David; Jacobson, Andrew D.; Batenburg, Sietske J.; Riquier, Laurent; MacLeod, Kenneth G.; Huber, Brian T. et al. (19 January 2023). "Abrupt episode of mid-Cretaceous ocean acidification triggered by massive volcanism". Nature Geoscience 16 (1): 169–174. doi:10.1038/s41561-022-01115-w. Bibcode2023NatGe..16..169J. https://www.nature.com/articles/s41561-022-01115-w. Retrieved 24 April 2023. 
  67. 67.0 67.1 "Submarine eruption bled Earth's oceans of oxygen". New Scientist. 16 July 2008. https://www.newscientist.com/article/mg19926655.300-submarine-eruption-bled-earths-oceans-of-oxygen.html. (Subscription content?)
  68. Chen, Hongjin; Xu, Zhaokai; Bayon, Germain; Lim, Dhongil; Batenburg, Sietske J.; Petrizzo, Maria Rose; Hasegawa, Takashi; Li, Tiegang (1 February 2022). "Enhanced hydrological cycle during Oceanic Anoxic Event 2 at southern high latitudes: New insights from IODP Site U1516". Global and Planetary Change 209: 103735. doi:10.1016/j.gloplacha.2022.103735. ISSN 0921-8181. https://www.sciencedirect.com/science/article/pii/S0921818122000029. Retrieved 30 December 2023. 
  69. Meyers, Philip A.; Bernasconi, Stefano M.; Forster, Astrid (December 2006). "Origins and accumulation of organic matter in expanded Albian to Santonian black shale sequences on the Demerara Rise, South American margin". Organic Geochemistry 37 (12): 1816–1830. doi:10.1016/j.orggeochem.2006.08.009. Bibcode2006OrGeo..37.1816M. https://www.sciencedirect.com/science/article/abs/pii/S0146638006002142. Retrieved 14 June 2023. 
  70. Kalanat, Behnaz; Vaziri-Moghaddam, Hossein (1 November 2019). "The Cenomanian/Turonian boundary interval deep-sea deposits in the Zagros Basin (SW Iran): Bioevents, carbon isotope record and palaeoceanographic model". Palaeogeography, Palaeoclimatology, Palaeoecology 533: 109238. doi:10.1016/j.palaeo.2019.109238. ISSN 0031-0182. https://www.sciencedirect.com/science/article/pii/S0031018219300987. Retrieved 25 September 2023. 
  71. 71.0 71.1 Kerr, Andrew C. (July 1998). "Oceanic plateau formation: a cause of mass extinction and black shale deposition around the Cenomanian–Turonian boundary?". Journal of the Geological Society 155 (4): 619–626. doi:10.1144/gsjgs.155.4.0619. Bibcode1998JGSoc.155..619K. https://www.researchgate.net/publication/228366167. Retrieved 17 March 2023. 
  72. Brčić, Vlatko; Glumac, Bosiljka; Fuček, Ladislav; Grizelj, Anita; Horvat, Marija; Posilović, Hrvoje; Mišur, Ivan (July 2017). "The Cenomanian–Turonian boundary in the northwestern part of the Adriatic Carbonate Platform (Ćićarija Mtn., Istria, Croatia): characteristics and implications". Facies 63 (3): 1–20. doi:10.1007/s10347-017-0499-7. https://www.researchgate.net/publication/316581707. Retrieved 2 July 2023. 
  73. Nagm, Emad; El-Qot, Gamal; Wilmsen, Markus (December 2014). "Stable-isotope stratigraphy of the Cenomanian–Turonian (Upper Cretaceous) boundary event (CTBE) in Wadi Qena, Eastern Desert, Egypt". Journal of African Earth Sciences 100: 524–531. doi:10.1016/j.jafrearsci.2014.07.023. ISSN 1464-343X. Bibcode2014JAfES.100..524N. https://www.sciencedirect.com/science/article/abs/pii/S1464343X14002428. Retrieved 17 March 2023. 
  74. Jenkyns, Hugh C. (March 2010). "Geochemistry of oceanic anoxic events: REVIEW". Geochemistry, Geophysics, Geosystems 11 (3): n/a. doi:10.1029/2009GC002788. Bibcode2010GGG....11.3004J. 
  75. Schlanger, S. O.; Arthur, M. A.; Jenkyns, Hugh C.; Scholle, P. A. (1987). "The Cenomanian-Turonian Oceanic Anoxic Event, I. Stratigraphy and distribution of organic carbon-rich beds and the marine δ 13 C excursion". Geological Society, London, Special Publications 26 (1): 371–399. doi:10.1144/GSL.SP.1987.026.01.24. ISSN 0305-8719. Bibcode1987GSLSP..26..371S. 
  76. 76.0 76.1 Sullivan, Daniel L.; Brandon, Alan D.; Eldrett, James; Bergman, Steven C.; Wright, Shawn; Minisini, Daniel (1 December 2020). "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 290: 424–425. doi:10.1016/j.gca.2020.09.022. ISSN 0016-7037. https://www.sciencedirect.com/science/article/pii/S001670372030586X. Retrieved 30 December 2023. 
  77. Jones, Matthew M.; Sageman, Bradley B.; Meyers, Stephen R. (20 April 2018). "Turonian Sea Level and Paleoclimatic Events in Astronomically Tuned Records From the Tropical North Atlantic and Western Interior Seaway" (in en). Paleoceanography and Paleoclimatology 33 (5): 470–492. doi:10.1029/2017PA003158. ISSN 2572-4517. https://onlinelibrary.wiley.com/doi/10.1029/2017PA003158. Retrieved 4 September 2023. 
  78. Wang, Xiangli; Reinhard, Christopher T.; Planavsky, Noah J.; Owens, Jeremy D.; Lyons, Timothy W.; Johnson, Thomas M. (1 July 2016). "Sedimentary chromium isotopic compositions across the Cretaceous OAE2 at Demerara Rise Site 1258". Chemical Geology 429: 85–92. doi:10.1016/j.chemgeo.2016.03.006. Bibcode2016ChGeo.429...85W. https://www.sciencedirect.com/science/article/abs/pii/S000925411630119X. Retrieved 14 June 2023. 
  79. Westermann, Stéphane; Vance, Derek; Cameron, Vyllinniskii; Archer, Corey; Robinson, Stuart A. (15 October 2014). "Heterogeneous oxygenation states in the Atlantic and Tethys oceans during Oceanic Anoxic Event 2" (in en). Earth and Planetary Science Letters 404: 178–189. doi:10.1016/j.epsl.2014.07.018. https://linkinghub.elsevier.com/retrieve/pii/S0012821X14004683. Retrieved 25 September 2023. 
  80. Goldberg, Tatiana; Poulton, Simon W.; Wagner, Thomas; Kolonic, Sadat F.; Rehkämper, Mark (15 April 2016). "Molybdenum drawdown during Cretaceous Oceanic Anoxic Event 2". Earth and Planetary Science Letters 440: 81–91. doi:10.1016/j.epsl.2016.02.006. Bibcode2016E&PSL.440...81G. https://www.sciencedirect.com/science/article/abs/pii/S0012821X16300176. Retrieved 14 June 2023. 
  81. Sinninghe Damsté, Jaap S.; Köster, Jürgen (30 May 1998). "A euxinic southern North Atlantic Ocean during the Cenomanian/Turonian oceanic anoxic event". Earth and Planetary Science Letters 158 (3–4): 165–173. doi:10.1016/S0012-821X(98)00052-1. Bibcode1998E&PSL.158..165S. https://www.sciencedirect.com/science/article/abs/pii/S0012821X98000521. Retrieved 14 June 2023. 
  82. Kuypers, Marcel M. M.; Pancost, Richard D.; Nijenhuis, Ivar A.; Sinninghe Damsté, Jaap S. (9 October 2002). "Enhanced productivity led to increased organic carbon burial in the euxinic North Atlantic basin during the late Cenomanian oceanic anoxic event". Paleoceanography and Paleoclimatology 17 (4): 3-1-3-13. doi:10.1029/2000PA000569. Bibcode2002PalOc..17.1051K. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2000PA000569. Retrieved 14 June 2023. 
  83. Pancost, Richard D.; Crawford, Neal; Magness, Simon; Turner, Andy; Jenkyns, Hugh C.; Maxwell, James R. (1 May 2004). "Further evidence for the development of photic-zone euxinic conditions during Mesozoic oceanic anoxic events". Journal of the Geological Society 161 (3): 353–364. doi:10.1144/0016764903-059. Bibcode2004JGSoc.161..353P. https://pubs.geoscienceworld.org/jgs/article-abstract/161/3/353/94311/Further-evidence-for-the-development-of-photic. Retrieved 14 June 2023. 
  84. Zhai, Ruixiang; Zeng, Zhiyu; Zhang, Ruiling; Yao, Weiqi (August 2023). "The response of nitrogen and sulfur cycles to ocean deoxygenation across the Cenomanian-Turonian boundary". Global and Planetary Change 227: 104182. doi:10.1016/j.gloplacha.2023.104182. Bibcode2023GPC...22704182Z. 
  85. Elderbak, Khalifa; Leckie, R. Mark (May 2016). "Paleocirculation and foraminiferal assemblages of the Cenomanian–Turonian Bridge Creek Limestone bedding couplets: Productivity vs. dilution during OAE2". Cretaceous Research 60: 52–77. doi:10.1016/j.cretres.2015.11.009. Bibcode2016CrRes..60...52E. https://www.sciencedirect.com/science/article/abs/pii/S019566711530118X. Retrieved 2 July 2023. 
  86. Hilbrecht, Heinz; Hubberten, Hans-W.; Oberhänsli, Hedwig (May 1992). "Biogeography of planktonic foraminifera and regional carbon isotope variations: productivity and water masses in late Cretaceous Europe". Palaeogeography, Palaeoclimatology, Palaeoecology 92 (3–4): 407–421. doi:10.1016/0031-0182(92)90093-K. Bibcode1992PPP....92..407H. https://www.sciencedirect.com/science/article/abs/pii/003101829290093K. Retrieved 2 July 2023. 
  87. Forster, Astrid; Kuypers, Marcel M. M.; Turgeon, Steven C.; Brumsack, Hans-J.; Petrizzo, Maria Rose; Sinninghe Damsté, Jaap S. (1 October 2008). "The Cenomanian/Turonian oceanic anoxic event in the South Atlantic: New insights from a geochemical study of DSDP Site 530A". Palaeogeography, Palaeoclimatology, Palaeoecology 267 (3–4): 256–283. doi:10.1016/j.palaeo.2008.07.006. Bibcode2008PPP...267..256F. https://www.sciencedirect.com/science/article/abs/pii/S0031018208004082. Retrieved 28 June 2023. 
  88. Orbitally driven redox fluctuations during Cretaceous Oceanic Anoxic Event 2 (OAE2) revealed by a new magnetic proxy
  89. 89.0 89.1 89.2 Mitchell, Ross N.; Bice, David M.; Montanari, Alessandro; Cleaveland, Laura C.; Christianson, Keith T.; Coccioni, Rodolfo; Hinnov, Linda A. (1 March 2008). "Oceanic anoxic cycles? Orbital prelude to the Bonarelli Level (OAE 2)". Earth and Planetary Science Letters 267 (1–2): 1–16. doi:10.1016/j.epsl.2007.11.026. Bibcode2008E&PSL.267....1M. https://www.sciencedirect.com/science/article/abs/pii/S0012821X07007546. Retrieved 2 January 2023. 
  90. 90.0 90.1 Coccioni, Rodolfo; Galeotti, Simone (15 January 2003). "The mid-Cenomanian Event: prelude to OAE 2". Palaeogeography, Palaeoclimatology, Palaeoecology 190: 427–440. doi:10.1016/S0031-0182(02)00617-X. Bibcode2003PPP...190..427C. https://www.researchgate.net/publication/223718129. Retrieved 22 January 2023. 
  91. Kuhnt, Wolfgang; Holbourn, Ann E.; Beil, Sebastian; Aquit, Mohamed; Krawczyk, Tim; Flögel, Sascha; Chellai, El Hassane; Jabour, Haddou (11 August 2017). "Unraveling the onset of Cretaceous Oceanic Anoxic Event 2 in an extended sediment archive from the Tarfaya-Laayoune Basin, Morocco". Paleoceanography and Paleoclimatology 32 (8): 923–946. doi:10.1002/2017PA003146. Bibcode2017PalOc..32..923K. https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2017PA003146. Retrieved 5 April 2023. 
  92. Dickson, Alexander J.; Saker-Clark, Matthew; Jenkyns, Hugh C.; Bottini, Cinzia; Erba, Elisabetta; Russo, Fabio; Gorbanenko, Olga; Naafs, Bernhard D. A. et al. (14 June 2016). "A Southern Hemisphere record of global trace-metal drawdown and orbital modulation of organic-matter burial across the Cenomanian–Turonian boundary (Ocean Drilling Program Site 1138, Kerguelen Plateau)". Sedimentology 64 (1): 186–203. doi:10.1111/sed.12303. https://onlinelibrary.wiley.com/doi/full/10.1111/sed.12303. Retrieved 7 April 2023. 
  93. Laurin, Jiří; Barclay, Richard S.; Sageman, Bradley B.; Dawson, Robin R.; Pagani, Mark; Schmitz, Mark; Eaton, Jeffrey; McInerney, Francesca A. et al. (15 June 2019). "Terrestrial and marginal-marine record of the mid-Cretaceous Oceanic Anoxic Event 2 (OAE 2): High-resolution framework, carbon isotopes, CO2 and sea-level change". Palaeogeography, Palaeoclimatology, Palaeoecology 524: 118–136. doi:10.1016/j.palaeo.2019.03.019. ISSN 0031-0182. https://www.sciencedirect.com/science/article/pii/S0031018218308277. Retrieved 30 December 2023. 
  94. Mort, Haydon P.; Adatte, Thierry; Keller, Gerta; Bartels, David; Föllmi, Karl B.; Steinmann, Philipp; Berner, Zsolt; Chellai, E. H. (October–December 2008). "Organic carbon deposition and phosphorus accumulation during Oceanic Anoxic Event 2 in Tarfaya, Morocco". Cretaceous Research 29 (5–6): 1008–1023. doi:10.1016/j.cretres.2008.05.026. Bibcode2008CrRes..29.1008M. https://www.sciencedirect.com/science/article/abs/pii/S0195667108000761. Retrieved 11 April 2023. 
  95. Beil, Sebastian; Kuhnt, Wolfgang; Holbourn, Ann; Scholtz, Florian; Oxmann, Julian; Wallmann, Klaus; Lorenzen, Janne; Aquit, Mohamed et al. (29 April 2020). "Cretaceous oceanic anoxic events prolonged by phosphorus cycle feedbacks". Climate of the Past 16 (2): 757–782. doi:10.5194/cp-16-757-2020. Bibcode2020CliPa..16..757B. https://cp.copernicus.org/articles/16/757/2020/. Retrieved 14 June 2023. 
  96. Poulton, Simon W.; Henkel, Susann; März, Christian; Urquhart, Hannah; Flögel, Sascha; Kasten, Sabine; Sinninghe Damsté, Jaap S.; Wagner, Thomas (1 November 2015). "A continental-weathering control on orbitally driven redox-nutrient cycling during Cretaceous Oceanic Anoxic Event 2". Geology 43 (11): 963–966. doi:10.1130/G36837.1. Bibcode2015Geo....43..963P. 
  97. Monteiro, F. M.; Pancost, Richard D.; Ridgwell, Andy; Donnadieu, Yannick (15 December 2012). "Nutrients as the dominant control on the spread of anoxia and euxinia across the Cenomanian-Turonian oceanic anoxic event (OAE2): Model-data comparison". Paleoceanography and Paleoclimatology 27 (4): 1–17. doi:10.1029/2012PA002351. Bibcode2012PalOc..27.4209M. 
  98. Karakitsios, Vassilis; Tsikos, Harilaos; van Breugel, Yvonne; Koletti, Lyda; Damsté, Jaap S. Sinninghe; Jenkyns, Hugh C. (2006). "First evidence for the Cenomanian–Turonian oceanic anoxic event (OAE2, 'Bonarelli' event) from the Ionian Zone, western continental Greece". International Journal of Earth Sciences 96 (2): 343–352. doi:10.1007/s00531-006-0096-4. Bibcode2007IJEaS..96..343K. http://eprints.ru.ac.za/645/1/tsikos_first_evidence.pdf. Retrieved 2020-03-11. 
  99. Ruebsam, Wolfgang; Schwark, Lorenz (May 2023). "Phytoplankton dynamics and nitrogen cycling during Oceanic Anoxic Event 2 (Cenomanian/Turonian) in the upwelling zone of the NE proto-North Atlantic". Global and Planetary Change 224: 104117. doi:10.1016/j.gloplacha.2023.104117. Bibcode2023GPC...22404117R. https://www.sciencedirect.com/science/article/abs/pii/S0921818123000905. Retrieved 2 July 2023. 
  100. Scholz, Florian; Beil, Sebastian; Flögel, Sascha; Lehmann, Moritz F.; Holbourn, Ann; Wallmann, Klaus; Kuhnt, Wolfgang (1 July 2019). "Oxygen minimum zone-type biogeochemical cycling in the Cenomanian-Turonian Proto-North Atlantic across Oceanic Anoxic Event 2". Earth and Planetary Science Letters 517: 50–60. doi:10.1016/j.epsl.2019.04.008. Bibcode2019E&PSL.517...50S. https://www.sciencedirect.com/science/article/abs/pii/S0012821X19302055. Retrieved 1 May 2023. 
  101. Pierce, Martin A.; Jarvis, Ian; Tocher, Bruce A. (1 September 2009). "The Cenomanian–Turonian boundary event, OAE2 and palaeoenvironmental change in epicontinental seas: New insights from the dinocyst and geochemical records". Palaeogeography, Palaeoclimatology, Palaeoecology 280 (1–2): 207–234. doi:10.1016/j.palaeo.2009.06.012. Bibcode2009PPP...280..207P. https://www.sciencedirect.com/science/article/abs/pii/S0031018209002272. Retrieved 28 January 2023. 
  102. Jenkyns, Hugh C. (March 1980). "Cretaceous anoxic events: from continents to oceans". Journal of the Geological Society 137 (2): 171–188. doi:10.1144/gsjgs.137.2.0171. Bibcode1980JGSoc.137..171J. https://www.lyellcollection.org/doi/abs/10.1144/gsjgs.137.2.0171. Retrieved 8 April 2023. 
  103. Al-Bassam, Khaldoun; Magna, Tomáš; Vodrážka, Radek; Čech, Stanislav (May 2019). "Mineralogy and geochemistry of marine glauconitic siliciclasts and phosphates in selected Cenomanian–Turonian units, Bohemian Cretaceous Basin, Czech Republic: Implications for provenance and depositional environment". Geochemistry 79 (2): 347–368. doi:10.1016/j.chemer.2019.05.003. Bibcode2019ChEG...79..347A. https://www.sciencedirect.com/science/article/abs/pii/S1611586418300192. Retrieved 12 April 2023. 
  104. Blättler, Clara L.; Jenkyns, Hugh C.; Reynard, Linda M.; Henderson, Gideon M. (1 September 2011). "Significant increases in global weathering during Oceanic Anoxic Events 1a and 2 indicated by calcium isotopes". Earth and Planetary Science Letters 309 (1–2): 77–88. doi:10.1016/j.epsl.2011.06.029. Bibcode2011E&PSL.309...77B. https://www.sciencedirect.com/science/article/abs/pii/S0012821X11004006. Retrieved 8 April 2023. 
  105. Chen, Hongjin; Bayon, Germain; Xu, Zhaokai; Li, Tiegang (1 January 2023). "Hafnium isotope evidence for enhanced weatherability at high southern latitudes during Oceanic Anoxic Event 2". Earth and Planetary Science Letters 601: 117910. doi:10.1016/j.epsl.2022.117910. Bibcode2023E&PSL.60117910C. 
  106. Sachs, Sven; Grant-Mackie, Jack A. (March 2003). "An ichthyosaur fragment from the Cretaceous of Northland, New Zealand". Journal of the Royal Society of New Zealand 33 (1): 307–314. doi:10.1080/03014223.2003.9517732. https://www.researchgate.net/publication/37988379. Retrieved 2 April 2023. 
  107. Erbacher, Jochen; Thurow, Jürgen; Littke, Ralf (1 June 1996). "Evolution patterns of radiolaria and organic matter variations: A new approach to identify sea-level changes in mid-Cretaceous pelagic environments". Geology 24 (6): 499–502. doi:10.1130/0091-7613(1996)024<0499:EPORAO>2.3.CO;2. Bibcode1996Geo....24..499E. https://pubs.geoscienceworld.org/gsa/geology/article-abstract/24/6/499/190794/Evolution-patterns-of-radiolaria-and-organic. Retrieved 2 July 2023. 
  108. Gertsch, B.; Keller, G.; Adatte, Thierry; Berner, Z.; Kassab, A. S.; Tantawy, A. A. A.; El-Sabbagh, A. M.; Stueben, D. (22 October 2008). "Cenomanian–Turonian transition in a shallow water sequence of the Sinai, Egypt". International Journal of Earth Sciences 99: 165–182. doi:10.1007/s00531-008-0374-4. https://link.springer.com/article/10.1007/s00531-008-0374-4?error=cookies_not_supported&code=ea1fa292-957c-463e-adf3-cc889831ff4a. Retrieved 11 April 2023. 
  109. Petrizzo, Maria Rose; Watkins, David K.; MacLeod, Kenneth G.; Hasegawa, Takashi; Huber, Brian T.; Batenburg, Sietske J.; Kato, Tomonori (November 2021). "Exploring the paleoceanographic changes registered by planktonic foraminifera across the Cenomanian-Turonian boundary interval and Oceanic Anoxic Event 2 at southern high latitudes in the Mentelle Basin (SE Indian Ocean)" (in en). Global and Planetary Change 206: 103595. doi:10.1016/j.gloplacha.2021.103595. https://linkinghub.elsevier.com/retrieve/pii/S0921818121001806. Retrieved 30 December 2023. 
  110. 110.0 110.1 Melinte-Dobrinescu, Mihaela Carmen; Bojar, Ana-Voica (October–December 2008). "Biostratigraphic and isotopic record of the Cenomanian–Turonian deposits in the Ohaba-Ponor section (SW Haţeg, Romania)". Cretaceous Research 29 (5–6): 1024–1034. doi:10.1016/j.cretres.2008.05.018. Bibcode2008CrRes..29.1024M. https://www.sciencedirect.com/science/article/abs/pii/S0195667108000785. Retrieved 2 April 2023. 
  111. Linnert, Christian; Mutterlose, Jörg; Erbacher, Jochen (February 2010). "Calcareous nannofossils of the Cenomanian/Turonian boundary interval from the Boreal Realm (Wunstorf, northwest Germany)". Marine Micropaleontology 74 (1–2): 38–58. doi:10.1016/j.marmicro.2009.12.002. ISSN 0377-8398. Bibcode2010MarMP..74...38L. 
  112. Faucher, G.; Erba, Elisabetta; Bottini, Cinzia (2013). "Life in extreme Oceans: Calcareous Nannoplankton adaptations and strategies during Oceanic Anoxic Event 2". Journal of Nannoplankton Research. https://air.unimi.it/handle/2434/225428. Retrieved 21 April 2023. 
  113. Erbacher, J.; Thurow, J. (March 1997). "Influence of oceanic anoxic events on the evolution of mid-Cretaceous radiolaria in the North Atlantic and western Tethys". Marine Micropaleontology 30 (1–3): 139–158. doi:10.1016/S0377-8398(96)00023-0. Bibcode1997MarMP..30..139E. https://www.sciencedirect.com/science/article/abs/pii/S0377839896000230. Retrieved 19 April 2023. 
  114. Johnson, C. C.; Kauffman, Erle G. (23 November 2005). "Originations, radiations and extinctions of Cretaceous rudistid bivalve species in the Caribbean Province". Extinction Events in Earth History. Berlin: Springer. pp. 305–324. doi:10.1007/BFb0011154. ISBN 978-3-540-47071-7. https://link.springer.com/chapter/10.1007/BFb0011154. 
  115. Naimi, Mohammed Nadir; Cherif, Amine; Mahboubi, Chikh Younes; Benyoucef, Madani (10 June 2022). "Ichnology of the Cenomanian–Turonian boundary event in the southern Tethyan margin (Khanguet Grouz section, Ouled Nail Range, Algeria)". Arabian Journal of Geosciences 15 (12). doi:10.1007/s12517-022-10420-y. https://link.springer.com/article/10.1007/s12517-022-10420-y. Retrieved 9 April 2023. 
  116. Prauss, Michael L. (April 2012). "The Cenomanian/Turonian Boundary event (CTBE) at Tarfaya, Morocco: Palaeoecological aspects as reflected by marine palynology". Cretaceous Research 34: 233–256. doi:10.1016/j.cretres.2011.11.004. ISSN 0195-6671. Bibcode2012CrRes..34..233P. 
  117. Fonseca, Carolina; Mendonça Filho, João Graciano; Lézin, Carine; de Oliveira, António Donizeti; Duarte, Luís V. (December 2019). "Organic matter deposition and paleoenvironmental implications across the Cenomanian-Turonian boundary of the Subalpine Basin (SE France): Local and global controls". International Journal of Coal Geology 218: 103364. doi:10.1016/j.coal.2019.103364. 
  118. Eaton, Jeffrey G.; Kirkland, James I.; Hutchinson, J. Howard; Denton, Robert; O'Neill, Robert C.; Parrish, J. Michael (1 May 1997). "Nonmarine extinction across the Cenomanian-Turonian boundary, southwestern Utah, with a comparison to the Cretaceous-Tertiary extinction event". Geological Society of America Bulletin 109 (5): 560–567. doi:10.1130/0016-7606(1997)109<0560:NEATCT>2.3.CO;2. Bibcode1997GSAB..109..560E. https://pubs.geoscienceworld.org/gsa/gsabulletin/article-abstract/109/5/560/183244/Nonmarine-extinction-across-the-Cenomanian. Retrieved 2 April 2023. 
  119. Galasso, Francesca; Heimhofer, Ulrich; Schneebeli-Hermann, Elke (22 February 2023). "The Cenomanian/Turonian boundary in light of new developments in terrestrial palynology". Scientific Reports 13 (1): 3074. doi:10.1038/s41598-023-30072-6. PMID 36813802. Bibcode2023NatSR..13.3074G. 

Further reading