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Swaby EJ, Coe AL, Ansorge J, Caswell BA, Hayward SAL, Mander L, Stevens LG, McArdle A. The fossil insect assemblage associated with the Toarcian (Lower Jurassic) oceanic anoxic event from Alderton Hill, Gloucestershire, UK. PLoS One 2024; 19:e0299551. [PMID: 38630753 PMCID: PMC11023202 DOI: 10.1371/journal.pone.0299551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 02/12/2024] [Indexed: 04/19/2024] Open
Abstract
Extreme global warming and environmental changes associated with the Toarcian (Lower Jurassic) Oceanic Anoxic Event (T-OAE, ~183 Mya) profoundly impacted marine organisms and terrestrial plants. Despite the exceptionally elevated abundances of fossil insects from strata of this age, only assemblages from Germany and Luxembourg have been studied in detail. Here, we focus on the insect assemblage found in strata recording the T-OAE at Alderton Hill, Gloucestershire, UK, where <15% of specimens have previously been described. We located all known fossil insects (n = 370) from Alderton Hill, and used these to create the first comprehensive taxonomic and taphonomic analysis of the entire assemblage. We show that a diverse palaeoentomofaunal assemblage is preserved, comprising 12 orders, 21 families, 23 genera and 21 species. Fossil disarticulation is consistent with insect decay studies. The number of orders is comparable with present-day assemblages from similar latitudes (30°-40°N), including the Azores, and suggests that the palaeoentomofauna reflects a life assemblage. At Alderton, Hemiptera, Coleoptera and Orthoptera are the commonest (56.1%) orders. The high abundance of Hemiptera (22.1%) and Orthoptera (13.4%) indicates well-vegetated islands, while floral changes related to the T-OAE may be responsible for hemipteran diversification. Predatory insects are relatively abundant (~10% of the total assemblage) and we hypothesise that the co-occurrence of fish and insects within the T-OAE represents a jubilee-like event. The marginally higher proportion of sclerotised taxa compared to present-day insect assemblages possibly indicates adaptation to environmental conditions or taphonomic bias. The coeval palaeoentomofauna from Strawberry Bank, Somerset is less diverse (9 orders, 12 families, 6 genera, 3 species) and is taphonomically biased. The Alderton Hill palaeoentomofauna is interpreted to be the best-preserved and most representative insect assemblage from Toarcian strata in the UK. This study provides an essential first step towards understanding the likely influence of the T-OAE on insects.
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Affiliation(s)
- Emily J. Swaby
- School of Environment, Earth and Ecosystem Sciences, The Open University, Walton Hall, Milton Keynes, Buckinghamshire, United Kingdom
| | - Angela L. Coe
- School of Environment, Earth and Ecosystem Sciences, The Open University, Walton Hall, Milton Keynes, Buckinghamshire, United Kingdom
| | - Jörg Ansorge
- Institut für Geologische Wissenschaften, Ernst-Moritz-Arndt-Universität Greifswald, Greifswald, Germany
| | - Bryony A. Caswell
- School of Environmental Science, Faculty of Science and Engineering, University of Hull, Hull, United Kingdom
| | - Scott A. L. Hayward
- School of Biosciences, University of Birmingham, Birmingham, United Kingdom
- Birmingham Institute of Forest Research, University of Birmingham, Birmingham, United Kingdom
| | - Luke Mander
- School of Environment, Earth and Ecosystem Sciences, The Open University, Walton Hall, Milton Keynes, Buckinghamshire, United Kingdom
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Yan Q, Li X, Kemp DB, Guo J, Zhang Z, Hu Y. Elevated atmospheric CO 2 drove an increase in tropical cyclone intensity during the early Toarcian hyperthermal. Proc Natl Acad Sci U S A 2023; 120:e2301018120. [PMID: 37428924 PMCID: PMC10629555 DOI: 10.1073/pnas.2301018120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 05/11/2023] [Indexed: 07/12/2023] Open
Abstract
The occurrence of sedimentary storm deposits around the Tethys Ocean during the early Toarcian hyperthermal (~183 Ma) suggests that intensified tropical cyclone (TC) activity occurred in response to CO2 rise and marked warming. However, this hypothesized linkage between extreme warmth and storm activity remains untested, and the spatial pattern of any changes in TCs is unclear. Here, model results show that there were two potential storm genesis centers over Tethys during the early Toarcian hyperthermal located around the northwestern and southeastern Tethys. The empirically determined doubling of CO2 concentration that accompanied the early Toarcian hyperthermal (~500 to ~1,000 ppmv) leads to increased probability of stronger storms over Tethys, in tandem with more favorable conditions for coastal erosion. These results match well with the geological occurrence of storm deposits during the early Toarcian hyperthermal and confirm that increased TC intensity would have accompanied global warming.
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Affiliation(s)
- Qing Yan
- Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing100029, China
- Key Laboratory of Meteorological Disaster/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing210044, China
| | - Xiang Li
- Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing100871, China
| | - David B. Kemp
- State Key Laboratory of Biogeology and Environmental Geology and Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan430074China
| | - Jiaqi Guo
- Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing100871, China
| | - Zhongshi Zhang
- Department of Atmospheric Science, School of Environmental Studies, China University of Geosciences, Wuhan430074, China
| | - Yongyun Hu
- Laboratory for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing100871, China
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Alnazghah M, Koeshidayatullah A, Al-Hussaini A, Amao A, Song H, Al-Ramadan K. Evidence for the early Toarcian Carbon Isotope Excursion (T-CIE) from the shallow marine siliciclastic red beds of Arabia. Sci Rep 2022; 12:18124. [PMID: 36302804 PMCID: PMC9613744 DOI: 10.1038/s41598-022-21716-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 09/30/2022] [Indexed: 12/30/2022] Open
Abstract
The Toarcian Oceanic Anoxic Event (T-OAE) and its corresponding Carbon Isotope Excursion (CIE) have been reported widely across the Tethyan region and globally. In Arabia, and based on ammonite dating, the time window of the T-OAE coincided with the deposition of the reddish siliciclastic unit of the Marrat Formation. However, no evidence of the T-OAE/CIE was ever reported from Arabia because these red beds were previously interpreted as continental deposits. Recently, these red beds have been recognized as shallow marine deposits which opened an opportunity to assess the occurrence and expression of T-OAE-CIE in Arabia. In this study, a multiproxy geochemical characterization was performed on the Toarcian Marrat Formation to infer the chemistry of the paleowater column and identify intervals of possible T-OAE/CIE in Arabia. While the low concentrations of redox-sensitive elements (Mo, U, V, Cr) may indicate a shallow oxic marine settings, the coupled negative δ13Corganic excursion and apparent increase in the chemical weathering suggests that the deposition of Marrat red beds coincided with the development of T-CIE and possibly time-equivalent to the T-OAE globally. The origin of reddening is interpreted to have occurred during the middle Marrat deposition due to the stabilization of unstable hydrous iron oxides to hematite under oxic marine conditions. The proposed model further indicates the possible development of source rocks in the deep, anoxic environment counterpart where the T-OAE may be expressed. Since our study documents the first record of the T-CIE and discuss the origin of shallow marine siliciclastic red beds in the Arabian Plate, this will have significant implications for the overall understanding of the T-CIE globally and for hydrocarbon exploration through realizations of potential new source rocks associated with the OAEs in the Toarcian and other time intervals.
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Affiliation(s)
- Mahmoud Alnazghah
- grid.454873.90000 0000 9113 8494Exploration Organization, Saudi Aramco, Dhahran, Saudi Arabia
| | - Ardiansyah Koeshidayatullah
- grid.412135.00000 0001 1091 0356Department of Geosciences, College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia ,grid.412135.00000 0001 1091 0356Center for Integrative Petroleum Research, College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
| | - Abdulkarim Al-Hussaini
- grid.454873.90000 0000 9113 8494Exploration Organization, Saudi Aramco, Dhahran, Saudi Arabia
| | - Abduljamiu Amao
- grid.412135.00000 0001 1091 0356Center for Integrative Petroleum Research, College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
| | - Haijun Song
- grid.503241.10000 0004 1760 9015State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Khalid Al-Ramadan
- grid.412135.00000 0001 1091 0356Department of Geosciences, College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia ,grid.412135.00000 0001 1091 0356Center for Integrative Petroleum Research, College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
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Ajuaba S, Sachsenhofer RF, Bechtel A, Galasso F, Gross D, Misch D, Schneebeli-Hermann E. Biomarker and compound-specific isotope records across the Toarcian CIE at the Dormettingen section in SW Germany. Int J Earth Sci 2022; 111:1631-1661. [PMID: 35707060 PMCID: PMC9188539 DOI: 10.1007/s00531-022-02196-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 04/14/2022] [Indexed: 06/15/2023]
Abstract
The Toarcian oceanic anoxic event (T-OAE) is associated with a prominent negative carbon isotope excursion (CIE; ~ 183 million years (Myr)). About 10-m-thick organic matter-rich sediments accumulated during the T-OAE in the Southwest German Basin (SWGB). Rock-Eval, maceral and biomarker analysis were used to determine variations of environmental conditions across the CIE interval. Carbon isotope records were determined for various n-alkanes, pristane and phytane to contribute to the reconstruction of the paleo-environment and to study the factors controlling molecular δ13C values. Geochemical redox indicators provide evidence for photic zone anoxia during the Toarcian CIE, which reached its maximum after deposition of the "Unterer Stein" marker horizon. The 2α-methylhopane index suggests enhanced activity of diazotrophic cyanobacteria, which is also supported by nitrogen isotope data. This distinguishes the SWGB from other basins with Toarcian black shale. Oxygen-depleted conditions, albeit with lower intensity continued after the CIE. All investigated compounds replicate the negative CIE, but the magnitudes vary considerably. The largest shift is observed for n-C27 (9‰) and reflects the combined effect of the global CIE and a major change in organic matter input (termination of terrigenous organic matter input). The shift for short-chain n-alkanes, pristane, and phytane, interpreted to reflect marine biomass, varies between 4.5 and 5.0‰. This is the highest value observed so far for any Toarcian section. δ13C values of pristane and phytane reach a minimum near the base of the CIE interval and increase upsection. Thus, the maximum negative isotope shift predates the strongest basin restriction by about 450 thousand years (kyr).
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Affiliation(s)
- Stephen Ajuaba
- Lehrstuhl Erdölgeologie, Montanuniversitaet Leoben, Peter-Tunner-Strasse 5, 8700 Leoben, Austria
| | - Reinhard F. Sachsenhofer
- Lehrstuhl Erdölgeologie, Montanuniversitaet Leoben, Peter-Tunner-Strasse 5, 8700 Leoben, Austria
| | - Achim Bechtel
- Lehrstuhl Erdölgeologie, Montanuniversitaet Leoben, Peter-Tunner-Strasse 5, 8700 Leoben, Austria
| | - Francesca Galasso
- Paläontologisches Institut und Museum, Universität Zürich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland
| | - Doris Gross
- Lehrstuhl Erdölgeologie, Montanuniversitaet Leoben, Peter-Tunner-Strasse 5, 8700 Leoben, Austria
| | - David Misch
- Lehrstuhl Erdölgeologie, Montanuniversitaet Leoben, Peter-Tunner-Strasse 5, 8700 Leoben, Austria
| | - Elke Schneebeli-Hermann
- Paläontologisches Institut und Museum, Universität Zürich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland
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Slater SM, Bown P, Twitchett RJ, Danise S, Vajda V. Global record of "ghost" nannofossils reveals plankton resilience to high CO 2 and warming. Science 2022; 376:853-856. [PMID: 35587965 DOI: 10.1126/science.abm7330] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Predictions of how marine calcifying organisms will respond to climate change rely heavily on the fossil record of nannoplankton. Declines in calcium carbonate (CaCO3) and nannofossil abundance through several past global warming events have been interpreted as biocalcification crises caused by ocean acidification and related factors. We present a global record of imprint-or "ghost"-nannofossils that contradicts this view, revealing exquisitely preserved nannoplankton throughout an inferred Jurassic biocalcification crisis. Imprints from two further Cretaceous warming events confirm that the fossil records of these intervals have been strongly distorted by CaCO3 dissolution. Although the rapidity of present-day climate change exceeds the temporal resolution of most fossil records, complicating direct comparison with past warming events, our findings demonstrate that nannoplankton were more resilient to past events than traditional fossil evidence suggests.
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Affiliation(s)
- Sam M Slater
- Department of Palaeobiology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden
| | - Paul Bown
- Department of Earth Sciences, University College London, London WC1E 6BT, UK
| | - Richard J Twitchett
- Department of Earth Sciences, The Natural History Museum, London SW7 5BD, UK
| | - Silvia Danise
- Dipartimento di Scienze della Terra, Università degli Studi di Firenze, Via La Pira 4, 50121 Firenze, Italy
| | - Vivi Vajda
- Department of Palaeobiology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden
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Font E, Duarte LV, Dekkers MJ, Remazeilles C, Egli R, Spangenberg JE, Fantasia A, Ribeiro J, Gomes E, Mirão J, Adatte T. Rapid light carbon releases and increased aridity linked to Karoo–Ferrar magmatism during the early Toarcian oceanic anoxic event. Sci Rep 2022; 12:4342. [PMID: 35288615 PMCID: PMC8921222 DOI: 10.1038/s41598-022-08269-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 03/03/2022] [Indexed: 11/09/2022] Open
Abstract
Large-scale release of isotopically light carbon is responsible for the carbon isotope excursion (CIE) of the Toarcian Oceanic Anoxic Event during the Lower Jurassic. Proposed sources include methane hydrate dissociation, volcanogenic outgassing of carbon dioxide and/or thermogenic methane release from the Karoo‐Ferrar magmatic province (southern Africa). Distinct small-scale shifts superimposed on the long-term CIE have been interpreted as rapid methane pulses linked to astronomically forced climate changes. In the Peniche reference section (Portugal), these small-scale shifts correspond to distinct brownish marly layers featuring markedly high mercury (Hg) and magnetic mineral concentration. Total organic carbon and Hg increase are uncorrelated, which suggests input of Hg into the atmosphere, possibly released after the intrusion of the Karoo-Ferrar sills into organic-rich sediments. Enhanced magnetic properties are associated with the presence of martite, washed-in oxidized magnetite, inferred to be due to increased aridity on the continental hinterland. This study provides strong evidence for a direct link between the Karoo-Ferrar magmatism, the carbon-isotope shifts and the resulting environmental changes.
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Heimdal TH, Goddéris Y, Jones MT, Svensen HH. Assessing the importance of thermogenic degassing from the Karoo Large Igneous Province (LIP) in driving Toarcian carbon cycle perturbations. Nat Commun 2021; 12:6221. [PMID: 34711826 PMCID: PMC8553747 DOI: 10.1038/s41467-021-26467-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 09/24/2021] [Indexed: 12/03/2022] Open
Abstract
The emplacement of the Karoo Large Igneous Province (LIP) occurred synchronously with the Toarcian crisis (ca. 183 Ma), which is characterized by major carbon cycle perturbations. A marked increase in the atmospheric concentration of CO2 (pCO2) attests to significant input of carbon, while negative carbon isotope excursions (CIEs) in marine and terrestrial records suggest the involvement of a 12C-enriched source. Here we explore the effects of pulsed carbon release from the Karoo LIP on atmospheric pCO2 and δ13C of marine sediments, using the GEOCLIM carbon cycle model. We show that a total of 20,500 Gt C replicates the Toarcian pCO2 and δ13C proxy data, and that thermogenic carbon (δ13C of -36 ‰) represents a plausible source for the observed negative CIEs. Importantly, an extremely isotopically depleted carbon source, such as methane clathrates, is not required in order to replicate the negative CIEs. Although exact values of individual degassing pulses represent estimates, we consider our emission scenario realistic as it incorporates the available geological knowledge of the Karoo LIP and a representative framework for Earth system processes during the Toarcian.
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Affiliation(s)
- Thea H. Heimdal
- grid.5510.10000 0004 1936 8921Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Oslo, Norway
| | - Yves Goddéris
- grid.462928.30000 0000 9033 1612Géosciences-Environnement Toulouse, CNRS-Université Paul Sabatier, Toulouse, France
| | - Morgan T. Jones
- grid.5510.10000 0004 1936 8921Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Oslo, Norway
| | - Henrik H. Svensen
- grid.5510.10000 0004 1936 8921Centre for Earth Evolution and Dynamics (CEED), University of Oslo, Oslo, Norway
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Wang Y, Ossa Ossa F, Wille M, Schurr S, Saussele ME, Schmid-Röhl A, Schoenberg R. Evidence for local carbon-cycle perturbations superimposed on the Toarcian carbon isotope excursion. Geobiology 2020; 18:682-709. [PMID: 32783292 DOI: 10.1111/gbi.12410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 07/09/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
A Jurassic negative carbon isotope excursion (CIE), co-evolved with Toarcian Oceanic Anoxic Event (OAE) at ~183 Ma, is suggested to be linked to a global carbon-cycle perturbation and is well documented for Toarcian terrestrial fossil woods and marine sediments around the globe. A theoretically coupled δ13 Ccarb -δ13 Corg pattern due to such dubbed global carbon-cycle event from the negative CIE in Dotternhausen Toarcian stratigraphic profile (southwest Germany) is unexpectedly disturbed by two-step δ13 Ccarb -δ13 Corg decoupling in which the last step, upper in the stratigraphic order, is of higher magnitude. However, the trigger(s) for these sudden decoupling disturbances are still poorly constrained. Here, connecting new carbon and oxygen isotope data with documentary lipid biomarkers shows that the global carbon cycle during the Toarcian OAE was disturbed by enhanced green sulfur bacteria (GSB) metabolisms and early diagenesis at local scales. The first step δ13 Ccarb -δ13 Corg decoupling was induced in the initial stage of the GSB bloom. The second step of much larger δ13 Ccarb -δ13 Corg decoupling arising from a GSB prosperity was, however, exaggerated by early diagenesis through the respiration of sulfate-reducing bacteria (SRB). Paleo-geographically distinct localities of the Tethys region show contrasting decoupled δ13 Ccarb -δ13 Corg patterns, which implies that the second-order carbon-cycle perturbations have pervasively and independently impacted the global carbon event during the Toarcian OAE.
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Affiliation(s)
- Yunfeng Wang
- Department of Geosciences, University of Tuebingen, Tuebingen, Germany
| | - Frantz Ossa Ossa
- Department of Geosciences, University of Tuebingen, Tuebingen, Germany
- Department of Geology, University of Johannesburg, Johannesburg, South Africa
| | - Martin Wille
- Institute of Geological Sciences, University of Bern, Bern, Switzerland
| | - Simon Schurr
- Institute of Geology and Paleontology, University of Muenster, Muenster, Germany
| | | | - Annette Schmid-Röhl
- Fossil Museum and Werkforum, Holcim (Süddeutschland) GmbH, Dotternhausen, Germany
| | - Ronny Schoenberg
- Department of Geosciences, University of Tuebingen, Tuebingen, Germany
- Department of Geology, University of Johannesburg, Johannesburg, South Africa
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Ullmann CV, Boyle R, Duarte LV, Hesselbo SP, Kasemann SA, Klein T, Lenton TM, Piazza V, Aberhan M. Warm afterglow from the Toarcian Oceanic Anoxic Event drives the success of deep-adapted brachiopods. Sci Rep 2020; 10:6549. [PMID: 32300235 DOI: 10.1038/s41598-020-63487-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 03/25/2020] [Indexed: 11/25/2022] Open
Abstract
Many aspects of the supposed hyperthermal Toarcian Oceanic Anoxic Event (T-OAE, Early Jurassic, c. 182 Ma) are well understood but a lack of robust palaeotemperature data severely limits reconstruction of the processes that drove the T-OAE and associated environmental and biotic changes. New oxygen isotope data from calcite shells of the benthic fauna suggest that bottom water temperatures in the western Tethys were elevated by c. 3.5 °C through the entire T-OAE. Modelling supports the idea that widespread marine anoxia was induced by a greenhouse-driven weathering pulse, and is compatible with the OAE duration being extended by limitation of the global silicate weathering flux. In the western Tethys Ocean, the later part of the T-OAE is characterized by abundant occurrences of the brachiopod Soaresirhynchia, which exhibits characteristics of slow-growing, deep sea brachiopods. The unlikely success of Soaresirhynchia in a hyperthermal event is attributed here to low metabolic rate, which put it at an advantage over other species from shallow epicontinental environments with higher metabolic demand.
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Oppo D, De Siena L, Kemp DB. A record of seafloor methane seepage across the last 150 million years. Sci Rep 2020; 10:2562. [PMID: 32054937 DOI: 10.1038/s41598-020-59431-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/29/2020] [Indexed: 11/29/2022] Open
Abstract
Seafloor methane seepage is a significant source of carbon in the marine environment. The processes and temporal patterns of seafloor methane seepage over multi-million-year time scales are still poorly understood. The microbial oxidation of methane can store carbon in sediments through precipitation of carbonate minerals, thus providing a record of past methane emission. In this study, we compiled data on methane-derived carbonates to build a proxy time series of methane emission over the last 150 My and statistically compared it with the main hypothesised geological controllers of methane emission. We quantitatively demonstrate that variations in sea level and organic carbon burial are the dominant controls on methane leakage since the Early Cretaceous. Sea level controls methane seepage variations by imposing smooth trends on timescales in the order of tens of My. Organic carbon burial is affected by the same cyclicities, and instantaneously controls methane release because of the geologically rapid generation of biogenic methane. Both the identified fundamental (26–27 My) and higher (12 My) cyclicities relate to global phenomena. Temporal correlation analysis supports the evidence that modern expansion of hypoxic areas and its effect on organic carbon burial may lead to higher seawater methane concentrations over the coming centuries.
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Abstract
Throughout Earth's history, variations in atmospheric CO2 concentration modulated climate. Understanding changes in atmospheric carbon cycle is therefore pivotal in predicting consequences of recent global warming. Here, we report stable carbon isotopes (δ13C) of molecular land plant fossils complemented by bulk organic and inorganic carbon fractions for early Toarcian (Early Jurassic) sediments that coincided with global warming and a carbon cycle perturbation. The carbon cycle perturbation is expressed by a negative excursion in the δ13C records established for the different substrates. Based on differences in the magnitude of the carbon isotope excursion recorded in land plants and marine substrates we infer that the early Toarcian warming was paralleled by an increase in atmospheric CO2 levels from ~500 ppmv to ~1000 ppmv. Our data suggest that rising atmospheric CO2 levels resulted from the injection of 12C-enriched methane and its subsequent oxidation to CO2. Based on the cyclic nature of the CIE we concluded that methane was released from climate sensitive reservoirs, in particular permafrost areas. Moderate volcanic CO2 emissions led to a destabilization of the labile permafrost carbon pool triggering the onset of Toarcian climate change only. The main carbon cycle perturbation then subsequently was driven by a self-sustained demise of a carbon-rich cryosphere progressing from mid to high latitudes as reflected by latitudinal climate gradients recorded in land plant carbon isotopes.
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Affiliation(s)
- Wolfgang Ruebsam
- Department of Organic and Isotope Geochemistry, Institute of Geoscience, University of Kiel, Kiel, Germany.
| | - Matías Reolid
- Departamento de Geología and CEACT, Universidad de Jaén, Jaén, Spain
| | - Lorenz Schwark
- Department of Organic and Isotope Geochemistry, Institute of Geoscience, University of Kiel, Kiel, Germany
- WA-OIGC, Curtin University, Perth, Australia
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12
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Them TR, Gill BC, Selby D, Gröcke DR, Friedman RM, Owens JD. Evidence for rapid weathering response to climatic warming during the Toarcian Oceanic Anoxic Event. Sci Rep 2017; 7:5003. [PMID: 28694487 PMCID: PMC5504049 DOI: 10.1038/s41598-017-05307-y] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 05/26/2017] [Indexed: 11/09/2022] Open
Abstract
Chemical weathering consumes atmospheric carbon dioxide through the breakdown of silicate minerals and is thought to stabilize Earth's long-term climate. However, the potential influence of silicate weathering on atmospheric pCO2 levels on geologically short timescales (103-105 years) remains poorly constrained. Here we focus on the record of a transient interval of severe climatic warming across the Toarcian Oceanic Anoxic Event or T-OAE from an open ocean sedimentary succession from western North America. Paired osmium isotope data and numerical modelling results suggest that weathering rates may have increased by 215% and potentially up to 530% compared to the pre-event baseline, which would have resulted in the sequestration of significant amounts of atmospheric CO2. This process would have also led to increased delivery of nutrients to the oceans and lakes stimulating bioproductivity and leading to the subsequent development of shallow-water anoxia, the hallmark of the T-OAE. This enhanced bioproductivity and anoxia would have resulted in elevated rates of organic matter burial that would have acted as an additional negative feedback on atmospheric pCO2 levels. Therefore, the enhanced weathering modulated by initially increased pCO2 levels would have operated as both a direct and indirect negative feedback to end the T-OAE.
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Affiliation(s)
- Theodore R Them
- Department of Geosciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24061, USA.
- Department of Earth, Ocean and Atmospheric Science & National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, 32306, USA.
| | - Benjamin C Gill
- Department of Geosciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24061, USA
| | - David Selby
- Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
| | - Darren R Gröcke
- Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
| | - Richard M Friedman
- Pacific Centre for Isotopic and Geochemical Research, Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Jeremy D Owens
- Department of Earth, Ocean and Atmospheric Science & National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, 32306, USA
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Pieńkowski G, Hodbod M, Ullmann CV. Fungal decomposition of terrestrial organic matter accelerated Early Jurassic climate warming. Sci Rep 2016; 6:31930. [PMID: 27554210 PMCID: PMC4995404 DOI: 10.1038/srep31930] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/26/2016] [Indexed: 12/04/2022] Open
Abstract
Soils - constituting the largest terrestrial carbon pool - are vulnerable to climatic warming. Currently existing uncertainties regarding carbon fluxes within terrestrial systems can be addressed by studies of past carbon cycle dynamics and related climate change recorded in sedimentary successions. Here we show an example from the Early Jurassic (early Toarcian, c. 183 mya) marginal-marine strata from Poland, tracking the hinterland response to climatic changes through a super-greenhouse event. In contrast to anoxia-related enhanced carbon storage in coeval open marine environments, Total Organic Carbon (TOC) concentrations in the Polish successions are substantially reduced during this event. Increasing temperature favoured fungal-mediated decomposition of plant litter - specifically of normally resistant woody tissues. The associated injection of oxidized organic matter into the atmosphere corresponds to abrupt changes in standing vegetation and may have contributed significantly to the amplified greenhouse climate on Earth. The characteristic Toarcian signature of multiple warm pulses coinciding with rapidly decreasing carbon isotope ratios may in part be the result of a radical reduction of the terrestrial carbon pool as a response to climate change.
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Affiliation(s)
- Grzegorz Pieńkowski
- Polish Geological Institute – National Research Institute, Rakowiecka 4, PL-00-975 Warszawa, Poland
| | - Marta Hodbod
- Polish Geological Institute – National Research Institute, Rakowiecka 4, PL-00-975 Warszawa, Poland
| | - Clemens V. Ullmann
- University of Exeter, Camborne School of Mines and Environment and Sustainability Institute, Penryn Campus, Penryn, Treliever Road, TE10 9FE, UK
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Ullmann CV, Thibault N, Ruhl M, Hesselbo SP, Korte C. Effect of a Jurassic oceanic anoxic event on belemnite ecology and evolution. Proc Natl Acad Sci U S A 2014; 111:10073-6. [PMID: 24982187 DOI: 10.1073/pnas.1320156111] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Toarcian oceanic anoxic event (T-OAE; ∼ 183 million y ago) is possibly the most extreme episode of widespread ocean oxygen deficiency in the Phanerozoic, coinciding with rapid atmospheric pCO2 increase and significant loss of biodiversity in marine faunas. The event is a unique past tipping point in the Earth system, where rapid and massive release of isotopically light carbon led to a major perturbation in the global carbon cycle as recorded in organic and inorganic C isotope records. Modern marine ecosystems are projected to experience major loss in biodiversity in response to enhanced ocean anoxia driven by anthropogenic release of greenhouse gases. Potential consequences of this anthropogenic forcing can be approximated by studying analog environmental perturbations in the past such as the T-OAE. Here we present to our knowledge the first organic carbon isotope record derived from the organic matrix in the calcite rostra of early Toarcian belemnites. We combine both organic and calcite carbon isotope analyses of individual specimens of these marine predators to obtain a refined reconstruction of the early Toarcian global exogenic carbon cycle perturbation and belemnite paleoecology. The organic carbon isotope data combined with measurements of oxygen isotope values from the same specimens allow for a more robust interpretation of the interplay between the global carbon cycle perturbation, environmental change, and biotic response during the T-OAE. We infer that belemnites adapted to environmental change by shifting their habitat from cold bottom waters to warm surface waters in response to expanded seafloor anoxia.
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15
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Abstract
AbstractWe consider the Anthropocene as a physical, chronostratigraphic unit across terrestrial and marine sedimentary facies, from both a present and a far future perspective, provisionally using an approximately 1950 CE base that approximates with the ‘Great Acceleration’, worldwide sedimentary incorporation of A-bomb-derived radionuclides and light nitrogen isotopes linked to the growth in fertilizer use, and other markers. More or less effective recognition of such a unit today (with annual/decadal resolution) is facies-dependent and variably compromised by the disturbance of stratigraphic superposition that commonly occurs at geologically brief temporal scales, and that particularly affects soils, deep marine deposits and the pre-1950 parts of current urban areas. The Anthropocene, thus, more than any other geological time unit, is locally affected by such blurring of its chronostratigraphic boundary with Holocene strata. Nevertheless, clearly separable representatives of an Anthropocene Series may be found in lakes, land ice, certain river/delta systems, in the widespread dredged parts of shallow-marine systems on continental shelves and slopes, and in those parts of deep-water systems where human-rafted debris is common. From a far future perspective, the boundary is likely to appear geologically instantaneous and stratigraphically significant.
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Affiliation(s)
- Jan Zalasiewicz
- Department of Geology, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Mark Williams
- Department of Geology, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Colin N. Waters
- British Geological Survey, Keyworth, Nottingham, NG12 5DP, UK
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16
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Danise S, Twitchett RJ, Little CTS, Clémence ME. The impact of global warming and anoxia on marine benthic community dynamics: an example from the Toarcian (Early Jurassic). PLoS One 2013; 8:e56255. [PMID: 23457537 PMCID: PMC3572952 DOI: 10.1371/journal.pone.0056255] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Accepted: 01/07/2013] [Indexed: 11/18/2022] Open
Abstract
The Pliensbachian-Toarcian (Early Jurassic) fossil record is an archive of natural data of benthic community response to global warming and marine long-term hypoxia and anoxia. In the early Toarcian mean temperatures increased by the same order of magnitude as that predicted for the near future; laminated, organic-rich, black shales were deposited in many shallow water epicontinental basins; and a biotic crisis occurred in the marine realm, with the extinction of approximately 5% of families and 26% of genera. High-resolution quantitative abundance data of benthic invertebrates were collected from the Cleveland Basin (North Yorkshire, UK), and analysed with multivariate statistical methods to detect how the fauna responded to environmental changes during the early Toarcian. Twelve biofacies were identified. Their changes through time closely resemble the pattern of faunal degradation and recovery observed in modern habitats affected by anoxia. All four successional stages of community structure recorded in modern studies are recognised in the fossil data (i.e. Stage III: climax; II: transitional; I: pioneer; 0: highly disturbed). Two main faunal turnover events occurred: (i) at the onset of anoxia, with the extinction of most benthic species and the survival of a few adapted to thrive in low-oxygen conditions (Stages I to 0) and (ii) in the recovery, when newly evolved species colonized the re-oxygenated soft sediments and the path of recovery did not retrace of pattern of ecological degradation (Stages I to II). The ordination of samples coupled with sedimentological and palaeotemperature proxy data indicate that the onset of anoxia and the extinction horizon coincide with both a rise in temperature and sea level. Our study of how faunal associations co-vary with long and short term sea level and temperature changes has implications for predicting the long-term effects of "dead zones" in modern oceans.
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Affiliation(s)
- Silvia Danise
- School of Geography, Earth and Environmental Sciences, Plymouth University, Plymouth, United Kingdom.
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Honisch B, Ridgwell A, Schmidt DN, Thomas E, Gibbs SJ, Sluijs A, Zeebe R, Kump L, Martindale RC, Greene SE, Kiessling W, Ries J, Zachos JC, Royer DL, Barker S, Marchitto TM, Moyer R, Pelejero C, Ziveri P, Foster GL, Williams B. The Geological Record of Ocean Acidification. Science 2012; 335:1058-63. [DOI: 10.1126/science.1208277] [Citation(s) in RCA: 672] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Affiliation(s)
- Micha Ruhl
- Palaeoecology, Institute of Environmental Biology, Faculty of Science, Utrecht University, Budapestlaan 4, NL-3584 CD, Utrecht, Netherlands
- Nordic Centre for Earth Evolution (NordCEE), Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, DK-1350, Copenhagen K, Denmark
| | - Nina R. Bonis
- Palaeoecology, Institute of Environmental Biology, Faculty of Science, Utrecht University, Budapestlaan 4, NL-3584 CD, Utrecht, Netherlands
- Shell Global Solutions International B.V., Kessler Park 1, 2288 GS, Rijswijk, Netherlands
| | - Gert-Jan Reichart
- Molecular Biogeochemistry, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Post Office Box 80.021, NL-3508 TA, Utrecht, Netherlands
| | - Jaap S. Sinninghe Damsté
- Molecular Biogeochemistry, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Post Office Box 80.021, NL-3508 TA, Utrecht, Netherlands
- Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Post Office Box 59, 1790 AB, Den Burg, Netherlands
| | - Wolfram M. Kürschner
- Palaeoecology, Institute of Environmental Biology, Faculty of Science, Utrecht University, Budapestlaan 4, NL-3584 CD, Utrecht, Netherlands
- Department of Geosciences, University of Oslo, Post Office Box 1047, Blindern, 0316 Oslo, Norway
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Zalasiewicz J, Williams M, Fortey R, Smith A, Barry TL, Coe AL, Bown PR, Rawson PF, Gale A, Gibbard P, Gregory FJ, Hounslow MW, Kerr AC, Pearson P, Knox R, Powell J, Waters C, Marshall J, Oates M, Stone P. Stratigraphy of the Anthropocene. Philos Trans A Math Phys Eng Sci 2011; 369:1036-55. [PMID: 21282159 DOI: 10.1098/rsta.2010.0315] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria. It is complex in time, space and process, and may be considered in terms of the scale, relative timing, duration and novelty of its various phenomena. The lithostratigraphic signal includes both direct components, such as urban constructions and man-made deposits, and indirect ones, such as sediment flux changes. Already widespread, these are producing a significant 'event layer', locally with considerable long-term preservation potential. Chemostratigraphic signals include new organic compounds, but are likely to be dominated by the effects of CO(2) release, particularly via acidification in the marine realm, and man-made radionuclides. The sequence stratigraphic signal is negligible to date, but may become geologically significant over centennial/millennial time scales. The rapidly growing biostratigraphic signal includes geologically novel aspects (the scale of globally transferred species) and geologically will have permanent effects.
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Affiliation(s)
- Jan Zalasiewicz
- Department of Geology, University of Leicester, Leicester LE1 7RH, UK.
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Whiteside JH, Olsen PE, Eglinton T, Brookfield ME, Sambrotto RN. Compound-specific carbon isotopes from Earth's largest flood basalt eruptions directly linked to the end-Triassic mass extinction. Proc Natl Acad Sci U S A 2010; 107:6721-5. [PMID: 20308590 DOI: 10.1073/pnas.1001706107] [Citation(s) in RCA: 180] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A leading hypothesis explaining Phanerozoic mass extinctions and associated carbon isotopic anomalies is the emission of greenhouse, other gases, and aerosols caused by eruptions of continental flood basalt provinces. However, the necessary serial relationship between these eruptions, isotopic excursions, and extinctions has never been tested in geological sections preserving all three records. The end-Triassic extinction (ETE) at 201.4 Ma is among the largest of these extinctions and is tied to a large negative carbon isotope excursion, reflecting perturbations of the carbon cycle including a transient increase in CO(2). The cause of the ETE has been inferred to be the eruption of the giant Central Atlantic magmatic province (CAMP). Here, we show that carbon isotopes of leaf wax derived lipids (n-alkanes), wood, and total organic carbon from two orbitally paced lacustrine sections interbedded with the CAMP in eastern North America show similar excursions to those seen in the mostly marine St. Audrie's Bay section in England. Based on these results, the ETE began synchronously in marine and terrestrial environments slightly before the oldest basalts in eastern North America but simultaneous with the eruption of the oldest flows in Morocco, a CO(2) super greenhouse, and marine biocalcification crisis. Because the temporal relationship between CAMP eruptions, mass extinction, and the carbon isotopic excursions are shown in the same place, this is the strongest case for a volcanic cause of a mass extinction to date.
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Kennedy M, Mrofka D, von der Borch C. Snowball Earth termination by destabilization of equatorial permafrost methane clathrate. Nature 2008; 453:642-5. [PMID: 18509441 DOI: 10.1038/nature06961] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2007] [Accepted: 03/18/2008] [Indexed: 11/09/2022]
Abstract
The start of the Ediacaran period is defined by one of the most severe climate change events recorded in Earth history--the recovery from the Marinoan 'snowball' ice age, approximately 635 Myr ago (ref. 1). Marinoan glacial-marine deposits occur at equatorial palaeolatitudes, and are sharply overlain by a thin interval of carbonate that preserves marine carbon and sulphur isotopic excursions of about -5 and +15 parts per thousand, respectively; these deposits are thought to record widespread oceanic carbonate precipitation during postglacial sea level rise. This abrupt transition records a climate system in profound disequilibrium and contrasts sharply with the cyclical stratigraphic signal imparted by the balanced feedbacks modulating Phanerozoic deglaciation. Hypotheses accounting for the abruptness of deglaciation include ice albedo feedback, deep-ocean out-gassing during post-glacial oceanic overturn or methane hydrate destabilization. Here we report the broadest range of oxygen isotope values yet measured in marine sediments (-25 per thousand to +12 per thousand) in methane seeps in Marinoan deglacial sediments underlying the cap carbonate. This range of values is likely to be the result of mixing between ice-sheet-derived meteoric waters and clathrate-derived fluids during the flushing and destabilization of a clathrate field by glacial meltwater. The equatorial palaeolatitude implies a highly volatile shelf permafrost pool that is an order of magnitude larger than that of the present day. A pool of this size could have provided a massive biogeochemical feedback capable of triggering deglaciation and accounting for the global postglacial marine carbon and sulphur isotopic excursions, abrupt unidirectional warming, cap carbonate deposition, and a marine oxygen crisis. Our findings suggest that methane released from low-latitude permafrost clathrates therefore acted as a trigger and/or strong positive feedback for deglaciation and warming. Methane hydrate destabilization is increasingly suspected as an important positive feedback to climate change that coincides with critical boundaries in the geological record and may represent one particularly important mechanism active during conditions of strong climate forcing.
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Affiliation(s)
- Martin Kennedy
- Department of Earth Science, University of California, Riverside, California 92521, USA.
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Abstract
Dramatic global warming, triggered by release of methane from clathrates, has been postulated to have occurred during the early Toarcian age in the Early Jurassic period. Kemp et al. claim that this methane was released at three points, as recorded by three sharp excursions of delta13C(org) of up to 3 per thousand magnitude. But they discount another explanation for the excursions: namely that some, perhaps all, of the rapid excursions could be a local signature of a euxinic basin caused by recycling of isotopically light carbon from the lower water column. This idea has been proposed previously (see ref. 3, for example) and is supported by the lack evidence for negative delta13C excursions in coeval belemnite rostra. Kemp et al. dismiss this alternative, claiming that each abrupt shift would have required the recycling of about double the amount of organic carbon that is currently present in the modern ocean; however, their measurements are not from an ocean but from a restricted, epicontinental seaway and so would not require whole-ocean mixing to achieve the excursions.
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Affiliation(s)
- Paul B Wignall
- School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK.
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Kemp DB, Coe AL, Cohen AS, Schwark L. Erratum: Astronomical pacing of methane release in the Early Jurassic period. Nature 2005; 438:696-696. [DOI: 10.1038/nature04361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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