The Paquier Event (OAE1b) was an oceanic anoxic event (OAE) that occurred around 111 million years ago (Ma), in the Albian geologic stage, during a climatic interval of Earth's history known as the Middle Cretaceous Hothouse (MKH).[1]

Causes

Pulsed volcanic activity of the Kerguelen Plateau is suggested to be the cause of OAE1b based on mercury anomalies recorded from this interval.[2] Five different mercury anomalies relative to total organic carbon are known from strata from the Jiuquan Basin spanning the OAE1b interval, strongly supporting a causal relationship with massive volcanism.[3] Prominent negative osmium isotope excursions coeval with biotic changes among planktonic foraminifera further confirm the occurrence of multiple episodes of submarine volcanic activity over the course of OAE1b.[4] Nonetheless, volcanism is not unequivocally supported as OAE1b's mainspring. Mercury anomalies associated with OAE1b have been interpreted by some to reflect mineralisation associated with salt diapirism instead of volcanism.[5] Another line of evidence contradicting the volcanism hypothesis involves the massive diachrony between thallium isotope records and intervals of deoxygenation.[6]

Global warming intensified chemical weathering, leading to increased terrestrial inputs of organic matter into oceans and lakes. This promoted eutrophication that rapidly depleted bodies of water of dissolved oxygen.[7] A contemporary increase in 187Os/188Os reflects an increase in continentally derived, radiogenic osmium sources in the ocean, confirming an increase in terrestrial runoff.[8]

Alternatively, rather than volcanism, some research points to orbital cycles as the governing cause of OAE1b. It has been hypothesised that enhanced monsoonal activity modulated by Earth's axial precession drove the development of OAE1b. Evidence supporting this explanation includes regular variations in detrital and weathering indices between humid intervals of high weathering and anoxia and drier intervals of decreased weathering and better oxygenated waters; these variations are suggested to correspond to precession cycles.[9] A different analysis of orbital forcing purports the long eccentricity cycle as the most significant orbital driver of monsoonal modulation.[10] δ18O records in planktic foraminifera from the Boreal Ocean show a 100 kyr periodicity, indicating that the short eccentricity cycle governed the ingression of hot Tethyan waters into the Boreal Ocean and consequent Boreal warming.[11] The 405 kyr eccentricity cycle appears to have dominated the advance and retreat of anoxia in the Vocontian Basin.[12]

The tectonic isolation of the Atlantic and Tethys Oceans restricted their ventilation, enabling their stagnation and facilitating ideal conditions for thermohaline stratification, which would in turn promote the widespread development of anoxia during a speedily warming climate.[13]

OAE1b's coincidence with a peak in a 5-6 Myr oscillation in marine phosphorus accumulation suggests that enhanced phosphorus regeneration may have been one of the causal factors behind the development of widespread anoxia. As more phosphorus built up in marine environments and caused spikes in biological productivity and decreases in dissolved oxygen, it caused a strong positive feedback loop in which phosphorus deposited on the seafloor was recycled back into the water column at faster rates, facilitating further increase in productivity and decrease in seawater oxygen content. Eventually, a negative feedback loop of increased atmospheric oxygen terminated this phosphorus spike and the OAE itself by causing increased wildfire activity and a consequent decline in vegetation and chemical weathering.[14]

Effects

Unlike other OAEs during the MKH, such as the OAE1a and the OAE2, OAE1b was not associated with an extinction event of benthic foraminifera. Identical benthic foraminiferal assemblages occur both below and above the black shales deposited in association with OAE1b, indicating that this OAE was limited in its geographic and bathymetric extent. Although some parts of the ocean floor became devoid of life, benthic foraminifera survived in refugia and recolonised previously abandoned areas after the OAE with no faunal turnover.[15] Planktonic foraminifera, however, significantly declined during OAE1b.[16] In the eastern Pacific, the Paquier Level of OAE1b is associated with the demise of heterozoan-dominated carbonate production.[17]


As with other OAEs, OAE1b left its mark on the geologic record in the form of widespread and abundant deposition of black shales.[18][19][1]

See also

References

  1. 1 2 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. Bibcode:2021ESRv..21503503S. doi:10.1016/j.earscirev.2021.103503. S2CID 233579194. Retrieved 24 May 2023.
  2. ↑ Sabatino, Nadia; Ferraro, Serena; Coccioni, Rodolfo; Bonsignore, Maria; Del Core, Marianna; Tancredi, Vincenzo; Sprovieri, Mario (15 April 2018). "Mercury anomalies in upper Aptian-lower Albian sediments from the Tethys realm". Palaeogeography, Palaeoclimatology, Palaeoecology. 495: 163–170. doi:10.1016/j.palaeo.2018.01.008. Retrieved 8 September 2023.
  3. ↑ Zhao, Xiangdong; Zheng, Daran; Wang, He; Feng, Yanan; Xue, Naihua; Zhang, Haichun (17 March 2022). "Carbon cycle perturbation and mercury anomalies in terrestrial Oceanic Anoxic Event 1b from Jiuquan Basin, NW China". Geological Society London Special Publications. 521 (1): 185–196. Bibcode:2022GSLSP.521..185Z. doi:10.1144/SP521-2021-149. Retrieved 3 June 2023.
  4. ↑ Matsumoto, Hironao; Kuroda, Junichiro; Coccioni, Rodolfo; Frontalini, Fabrizio; Sakai, Saburo; Ogawa, Nakano O.; Okhouchi, Naohiko (28 July 2020). "Marine Os isotopic evidence for multiple volcanic episodes during Cretaceous Oceanic Anoxic Event 1b". Scientific Reports. 10 (1): 12601. Bibcode:2020NatSR..1012601M. doi:10.1038/s41598-020-69505-x. PMC 7387342. PMID 32724064.
  5. ↑ Galloway, Jennifer S.; Grasby, Stephen E.; Wang, Feiyue; Hadlari, Thomas; Dewing, Keith; Bodin, Stéphane; Sanei, Hamed (1 May 2023). "A mercury and trace element geochemical record across Oceanic Anoxic Event 1b in Arctic Canada". Palaeogeography, Palaeoclimatology, Palaeoecology. 617: 111490. Bibcode:2023PPP...617k1490G. doi:10.1016/j.palaeo.2023.111490. S2CID 257457455. Retrieved 13 June 2023.
  6. ↑ Wang, Yi; Bodin, Stéphane; Blusztajn, Jerzy S.; Ullmann, Clemens V.; Nielsen, Sune G. (5 September 2022). "Orbitally paced global oceanic deoxygenation decoupled from volcanic CO2 emission during the middle Cretaceous Oceanic Anoxic Event 1b (Aptian-Albian transition)". Geology. 50 (11): 1324–1328. Bibcode:2022Geo....50.1324W. doi:10.1130/G50553.1. S2CID 252105117. Retrieved 13 June 2023.
  7. ↑ Xu, Xiao-Tao; Shao, Long-Yi; Eriksson, Kenneth A.; Pang, Bo; Wang, Shuai; Yang, Cheng-Xue; Hou, Hai-Hai (January 2022). "Terrestrial records of the early Albian Ocean Anoxic Event: Evidence from the Fuxin lacustrine basin, NE China". Geoscience Frontiers. 13 (1): 101275. doi:10.1016/j.gsf.2021.101275. hdl:10919/111675.
  8. ↑ Matsumoto, Hironao; Shirai, Kotaro; Huber, Brian T.; MacLeod, Kenneth G.; Kuroda, Junichiro (1 March 2023). "High-resolution marine osmium and carbon isotopic record across the Aptian–Albian boundary in the southern South Atlantic: Evidence for enhanced continental weathering and ocean acidification". Palaeogeography, Palaeoclimatology, Palaeoecology. 613: 111414. doi:10.1016/j.palaeo.2023.111414. S2CID 256164843. Retrieved 8 September 2023.
  9. ↑ Benamara, Asmahane; Charbonnier, Guillaume; Adatte, Thierry; Spangenberg, Jorge E.; Föllmi, Karl B. (1 January 2020). "Precession-driven monsoonal activity controlled the development of the early Albian Paquier oceanic anoxic event (OAE1b): Evidence from the Vocontian Basin, SE France". Palaeogeography, Palaeoclimatology, Palaeoecology. 537: 109406. Bibcode:2020PPP...537j9406B. doi:10.1016/j.palaeo.2019.109406. S2CID 210287467. Retrieved 3 June 2023.
  10. ↑ Bodin, Stéphane; Charpentier, Mickaël; Ullmann, Clemens V.; Rudra, Arka; Sanei, Hamed (March 2023). "Carbon cycle during the late Aptian–early Albian OAE 1b: A focus on the Kilian–Paquier levels interval". Global and Planetary Change. 222: 104074. Bibcode:2023GPC...22204074B. doi:10.1016/j.gloplacha.2023.104074. hdl:10871/133016. S2CID 257065486. Retrieved 13 June 2023.
  11. ↑ Erbacher, Jochen; Friedrich, Oliver; Wilson, Paul A.; Lehmann, Jens; Weiss, Wolfgang (1 March 2011). "Short-term warming events during the boreal Albian (mid‑Cretaceous)". Geology. 39 (3): 223–226. Bibcode:2011Geo....39..223E. doi:10.1130/G31606.1. Retrieved 13 June 2023.
  12. ↑ Ait-Itto, Fatima-Zahra; Martinez, Mathieu; Deconinck, Jean-François; Bodin, Stéphane (October 2023). "Astronomical calibration of the OAE1b from the Col de Pré-Guittard section (Aptian–Albian), Vocontian Basin, France". Cretaceous Research. 150: 105618. doi:10.1016/j.cretres.2023.105618. S2CID 259320646. Retrieved 8 September 2023.
  13. ↑ Erbacher, Jochen; Huber, Brian T.; Norris, Richard D.; Markey, Molly (18 January 2001). "Increased thermohaline stratification as a possible cause for an ocean anoxic event in the Cretaceous period". Nature. 409 (6818): 325–327. doi:10.1038/35053041. PMID 11201737. S2CID 4381092. Retrieved 13 June 2023.
  14. ↑ 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. Bibcode:2003GBioC..17.1092H. doi:10.1029/2003GB002039. S2CID 140194325. Retrieved 14 June 2023.
  15. ↑ Holbourn, Ann; Kuhnt, Wolfgang (2001). "No extinctions during Oceanic Anoxic Event 1b: the Aptian-Albian benthic foraminiferal record of ODP Leg 171". Geological Society London Special Publications. 183 (1): 73–92. Bibcode:2001GSLSP.183...73H. doi:10.1144/gsl.sp.2001.183.01.04. S2CID 128820488. Retrieved 3 June 2023.
  16. ↑ Huber, B. T.; Leckie, R. M. (1 January 2011). "Planktic Foraminiferal Species Turnover Across Deep-Sea Aptian/ Albian Boundary Sections". The Journal of Foraminiferal Research. 41 (1): 53–95. doi:10.2113/gsjfr.41.1.53. ISSN 0096-1191. Retrieved 8 September 2023.
  17. ↑ Navarro-Ramirez, J. P.; Bodin, S.; Heimhofer, U.; Immenhauser, A. (1 April 2015). "Record of Albian to early Cenomanian environmental perturbation in the eastern sub-equatorial Pacific". Palaeogeography, Palaeoclimatology, Palaeoecology. 423: 122–137. doi:10.1016/j.palaeo.2015.01.025. ISSN 0031-0182. Retrieved 28 September 2023.
  18. ↑ Tsikos, Harilaos; Karakitsios, Vassilios; Van Breugel, Yvonne; Walsworth-Bell, Ben; Bombardiere, Luca; Petrizzo, Maria Rose; Sinnighe Damste, Jaap S.; Schouten, Stefan; Erba, Elisabetta; Premoli Silva, Isabella; Farrimond, Paul; Tyson, Richard; Jenkyns, Hugh C. (July 2004). "Organic-carbon deposition in the Cretaceous of the Ionian Basin, NW-Greece : The Paquier Event (OAE 1b) re-visited". Geological Magazine. 141 (4): 401–416. Bibcode:2004GeoM..141..401T. doi:10.1017/S0016756804009409. S2CID 130984561. Retrieved 3 June 2023.
  19. ↑ Talbi, Rachida; Lakhdar, Rached; Smati, Amor; Spiller, Reginal; Levey, Raymond (16 November 2018). "Aptian–Albian shale oil unconventional system as registration of Cretaceous oceanic anoxic sub-events in the southern Tethys (Bir M'Cherga basin, Tunisia)". Journal of Petroleum Exploration and Production Technology. 9 (2): 1007–1022. doi:10.1007/s13202-018-0577-6. ISSN 2190-0558.


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