Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T09:53:29.019Z Has data issue: false hasContentIssue false

The chemostratigraphy and environmental significance of the Marlstone and Junction Bed (Beacon Limestone, Toarcian, Lower Jurassic, Dorset, UK)

Published online by Cambridge University Press:  02 November 2021

Hugh C. Jenkyns*
Affiliation:
Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK
Sophie Macfarlane
Affiliation:
Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK
*
Author for correspondence: Hugh C. Jenkyns, Email: [email protected]

Abstract

Two fallen blocks of the Marlstone and stratigraphically overlying Junction Bed sampled on the beach below Doghouse Cliff in Dorset, UK (Wessex Basin) have been examined for carbon and oxygen isotopes of bulk carbonate as well as for strontium, carbon and oxygen isotopes and Mg:Ca ratios in the contained belemnites. The sequence, which contains most of the Toarcian zones and subzones within a metre or less of grey to yellow to pink, red and brown fossil-rich nodular limestone, is extremely condensed and lithologically similar to pelagic red limestones of the Tethyan Jurassic that are locally mineralized with Fe-Mn oxyhydroxides (e.g., Rosso Ammonitico). Strontium-isotope ratios of the contained belemnites are compatible with existing reference curves and both blocks show a rise to more radiogenic values post-dating the Pliensbachian–Toarcian boundary. The high degree of correlation between the relatively negative carbon and oxygen isotopes of the bulk carbonate is compatible with significant diagenetic overprint, and contrasts with higher carbon-isotope values in coeval condensed coccolith-rich limestones elsewhere. Evidence for the characteristic signature of the Toarcian Oceanic Anoxic Event, as represented by organic-rich sediment, is absent, possibly owing to a stratigraphic gap. Both blocks exhibit abrupt carbon-isotope shifts to lower values, one of which could represent the limbs of an incompletely recorded negative excursion associated with the Toarcian Oceanic Anoxic Event. That the Toarcian Oceanic Anoxic Event was also a significant hyperthermal is illustrated in both blocks by a drop in oxygen-isotope values and rise in Mg:Ca ratios of belemnites close to the base of the Junction Bed in the lowest part of the serpentinum zone.

Type
Original Article
Copyright
© The Author(s), 2021. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ager, DV (1956) The geographical distribution of brachiopods in the British Middle Lias. Quarterly Journal of the Geological Society of London 112, 157–87.CrossRefGoogle Scholar
Ainsworth, NR, Braham, W, Gregory, FJ, Johnson, B and King, C (1998) The lithostratigraphy of the latest Triassic to earliest Cretaceous of the English Channel and its adjacent areas. In Development, Evolution and Petroleum Geology of the Wessex Basin (ed. Underhill, JR), pp. 103–64. Geological Society of London, Special Publication no. 133.Google Scholar
Ainsworth, NR and Riley, LA (2010) Triassic to Middle Jurassic stratigraphy of the Kerr McGee 97/12-1 exploration well, offshore southern England. Marine and Petroleum Geology 27, 853–84.CrossRefGoogle Scholar
Al-Suwaidi, AH, Angelozzi, GN, Baudin, F, Damborenea, SE, Hesselbo, SP, Jenkyns, HC, Manceñido, MO and Riccardi, AC (2010) First record of the Early Toarcian oceanic anoxic event from the Southern Hemisphere, Neuquén Basin, Argentina. Journal of the Geological Society, London 167, 633–6.CrossRefGoogle Scholar
Anderson, TF and Arthur, MA (1983) Stable isotopes of oxygen and carbon and their application to sedimentologic and paleoenvironmental problems. In Stable Isotopes in Sedimentary Geology (contributors Arthur, MA, Anderson, TF, Kaplan, IR, Veizer, J and Land, LS), pp. 1151. Society of Economic Paleontologists and Mineralogists Short Course No. 10.Google Scholar
Arkell, WJ (1933) The Jurassic System in Great Britain. London: Oxford University Press, 681 pp.Google Scholar
Bailey, TR, Rosenthal, Y, McArthur, JM, van de Schootbrugge, B and Thirlwall, MF (2003) Paleoceanographic changes of the Late Pliensbachian–Early Toarcian interval: a possible link to the genesis of an Oceanic Anoxic Event. Earth and Planetary Science Letters 212, 307–20.CrossRefGoogle Scholar
Bernoulli, D and Jenkyns, HC (1974) Alpine, Mediterranean and central Atlantic Mesozoic facies in relation to the early evolution of the Tethys. In Modern and Ancient Geosynclinal Sedimentation (eds Dott, RH Jr and Shaver, RH), pp. 129–60. Society of Economic Paleontologists and Mineralogists Special Publication 19.CrossRefGoogle Scholar
Bodin, S, Krencker, FN, Kothe, T, Hoffmann, R, Mattioli, E, Heimhofer, U and Kabiri, L (2016) Perturbation of the carbon cycle during the late Pliensbachian–early Toarcian: new insight from high-resolution carbon isotope records in Morocco. Journal of African Earth Sciences 116, 89104.CrossRefGoogle Scholar
Boomer, I, Copestake, P, Page, K, Huxtable, J, Loy, T, Bown, P, Jones, TD, O’Callaghan, M, Hawkes, S, Halfacree, D and Reay, H (2021) Biotic and stable-isotope characterization of the Toarcian Ocean Anoxic Event through a carbonate–clastic sequence from Somerset, UK. In Carbon Cycle and Ecosystem Response to the Jenkyns Event in the Early Toarcian (Jurassic) (eds Reolid, M, Duarte, LV, Mattioli, E and Ruebsam, W). Geological Society of London, Special Publication no. 514, published online 5 July 2021. doi: 10.1144/SP514-2020-263.Google Scholar
Boomer, I, Lord, AR, Page, KN, Bown, PR, Lowry, FMD and Riding, JB (2009) The biostratigraphy of the Upper Pliensbachian–Toarcian (Lower Jurassic) sequence at Ilminster, Somerset. Journal of Micropalaeontology 28, 6785.CrossRefGoogle Scholar
Buckman, SS (1922) Jurassic chronology: II—preliminary studies. Certain Jurassic strata near Eypesmouth (Dorset); the Junction-Bed of Watton Cliff and associated rocks. Quarterly Journal of the Geological Society of London 78, 378457.CrossRefGoogle Scholar
Caruthers, AH, Gröcke, DR and Smith, PL (2011) The significance of an Early Jurassic (Toarcian) carbon-isotope excursion in Haida Gwaii (Queen Charlotte Islands), British Columbia, Canada. Earth and Planetary Science Letters 307, 1926.CrossRefGoogle Scholar
Chadwick, RA (1986) Extension tectonics in the Wessex Basin, southern England. Journal of the Geological Society, London 143, 465–88.CrossRefGoogle Scholar
Conti, MA and Monari, S (2003) Jurassic discohelicid gastropods from the Reatini Mountains (central Apennines, Italy) and their stratigraphical significance. Geologica Romana 36, 199213.Google Scholar
Cope, JCW, Getty, TA, Howarth, MK, Morton, N and Torrens, HS (1980) A Correlation of Jurassic Rocks in the British Isles; Part One: Introduction and Lower Jurassic. Geological Society of London, Special Report No. 14, 73 pp.Google Scholar
Cox, BM, Sumbler, MG and Ivimey-Cook, HC (1999) A formational framework for the Lower Jurassic of England and Wales (Onshore Area). British Geological Survey Research Report RR/99/01, 25 pp.Google Scholar
Cronan, DS, Galácz, A, Mindszenty, A, Moorby, SA and Polgari, M (1991) Tethyan ferromanganese oxide deposits from Jurassic rocks in Hungary. Journal of the Geological Society, London 148, 655–68.CrossRefGoogle Scholar
da Rocha, RB, Mattioli, E, Duarte, L, Pittet, B, Elmi, S, Mouterde, R, Cabral, MC, Comas-Rengifo, M, Gómez, J, Goy, A, Hesselbo, S, Jenkyns, HC, Littler, K, Mailliot, S, de Oliveira, LCV, Osete, ML, Perilli, N, Pinto, S, Ruget, C and Suan, G (2016) Base of the Toarcian Stage of the Lower Jurassic defined by the Global Boundary Stratotype Section and Point (GSSP) at the Peniche section (Portugal). Episodes 39, 460–81.CrossRefGoogle Scholar
Dera, G, Brigaud, B, Monna, F, Laffont, R, Pucéat, E, Deconinck, J-F, Pellenard, P, Joachimski, MM and Durlet, C (2011a) Climatic ups and downs in a disturbed Jurassic world. Geology 39, 215–18.CrossRefGoogle Scholar
Dera, G, Neige, P, Dommergues, JL and Brayard, A (2011b) Ammonite paleobiogeography during the Pliensbachian–Toarcian crisis (Early Jurassic) reflecting paleoclimate, eustasy, and extinctions. Global and Planetary Change 78, 92105.CrossRefGoogle Scholar
Dickson, AJ, Gill, BC, Ruhl, M, Jenkyns, HC, Porcelli, D, Idiz, E, Lyons, TW and van den Boorn, SH (2017) Molybdenum-isotope chemostratigraphy and paleoceanography of the Toarcian Oceanic Anoxic Event (Early Jurassic). Paleoceanography 328, 13829.Google Scholar
Ettinger, NP, Larson, TE, Kerans, C, Thibodeau, AM, Hattori, KE, Kacur, SM and Martindale, RC (2021) Ocean acidification and photic-zone anoxia at the Toarcian Oceanic Anoxic Event: insights from the Adriatic Carbonate Platform. Sedimentology 68, 63107.CrossRefGoogle Scholar
Fantasia, A, Föllmi, KB, Adatte, T, Spangenberg, JE and Montero-Serrano, JC (2018) The Early Toarcian oceanic anoxic event: paleoenvironmental and paleoclimatic change across the Alpine Tethys (Switzerland). Global and Planetary Change 162, 5368.CrossRefGoogle Scholar
Ferguson, JE, Henderson, GM, Kucera, M and Rickaby, REM (2008) Systematic change of foraminiferal Mg/Ca ratios across a strong salinity gradient. Earth and Planetary Science Letters 265, 153–66.CrossRefGoogle Scholar
Fernandez, A, Korte, C, Ullmann, CV, Looser, N, Wohlwend, S and Bernasconi, SM (2021) Reconstructing the magnitude of Early Toarcian (Jurassic) warming using the reordered clumped isotope compositions of belemnites. Geochimica et Cosmochimica Acta 293, 308–27.CrossRefGoogle Scholar
Fischer, AG and Garrison, RE (1967) Carbonate lithification on the sea floor. Journal of Geology 75, 488–96.CrossRefGoogle Scholar
Föllmi, KB (2016) Sedimentary condensation. Earth-Science Reviews 152, 143–80.CrossRefGoogle Scholar
Gómez, JJ and Goy, A (2011) Warming-driven mass extinction in the Early Toarcian (Early Jurassic) of northern and central Spain. Correlation with other time-equivalent European sections. Palaeogeography, Palaeoclimatology, Palaeoecology 306, 176–95.CrossRefGoogle Scholar
Gröcke, D, Hesselbo, SP and Findlay, DJ (2007) Atypical diagenetic effects on strontium-isotope composition of Early Jurassic belemnites, Queen Charlotte Islands, British Columbia, Canada. Canadian Journal of Earth Sciences 44, 181–97.CrossRefGoogle Scholar
Hallam, A (1967) A sedimentary and faunal study of the Blue Lias of Dorset and Glamorgan. Philosophical Transactions of the Royal Society, Series B 243, 144.Google Scholar
Han, Z, Hu, X, Kemp, DB and Li, J (2018) Carbonate-platform response to the Toarcian Oceanic Anoxic Event in the southern hemisphere: implications for climatic change and biotic platform demise. Earth and Planetary Science Letters 489, 5971.CrossRefGoogle Scholar
Harazim, D, van de Schootbrugge, B, Sorichter, K, Fiebig, J, Weug, A, Suan, G and Oschmann, W (2013) Spatial variability of watermass conditions within the European Epicontinental Seaway during the Early Jurassic (Pliensbachian–Toarcian). Sedimentology 60, 359–90.CrossRefGoogle Scholar
Hermoso, M, Le Callonnec, L, Minoletti, F, Renard, M and Hesselbo, SP (2009) Expression of the Early Toarcian negative carbon-isotope excursion in separated carbonate microfractions (Jurassic, Paris Basin). Earth and Planetary Science Letters 277, 194203.CrossRefGoogle Scholar
Hermoso, M, Minoletti, F, Rickaby, RE, Hesselbo, SP, Baudin, F and Jenkyns, HC (2012) Dynamics of a stepped carbon-isotope excursion: ultra high-resolution study of Early Toarcian environmental change. Earth and Planetary Science Letters 319, 4554.CrossRefGoogle Scholar
Hermoso, M and Pellenard, P (2014) Continental weathering and climatic changes inferred from clay mineralogy and paired carbon isotopes across the early to middle Toarcian in the Paris Basin. Palaeogeography, Palaeoclimatology, Palaeoecology 399, 385–93.CrossRefGoogle Scholar
Hesselbo, SP, Gröcke, DR, Jenkyns, HC, Bjerrum, CJ, Farrimond, P, Morgans Bell, HS and Green, OR (2000) Massive dissociation of gas hydrate during a Jurassic oceanic anoxic event. Nature 406, 392–5.CrossRefGoogle ScholarPubMed
Hesselbo, SP and Jenkyns, HC (1995) A comparison of the Hettangian to Bajocian successions of Dorset and Yorkshire. In Field Geology of the British Jurassic (ed. Taylor, PD), pp. 105–50. London: Geological Society of London.Google Scholar
Hesselbo, SP, Jenkyns, HC, Duarte, LV and Oliveira, LC (2007) Carbon-isotope record of the Early Jurassic (Toarcian) Oceanic Anoxic Event from fossil wood and marine carbonate (Lusitanian Basin, Portugal). Earth and Planetary Science Letters 253, 455–70.CrossRefGoogle Scholar
Hönisch, 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 Jr, Moyer, R, Pelejero, C, Ziveri, P, Foster, GL and Williams, BC (2012) The geological record of ocean acidification. Science 335, 1058–63.CrossRefGoogle ScholarPubMed
Howarth, MK (1957) The middle Lias of the Dorset coast. Quarterly Journal of the Geological Society of London 113, 185204.CrossRefGoogle Scholar
Howarth, MK (1980) The Toarcian age of the upper part of the Marlstone Rock Bed of England. Palaeontology 23, 637–56.Google Scholar
Howarth, MK (1992) The ammonite family Hildoceratidae in the Lower Jurassic of Britain. Part 1. Monograph of the Palaeontographical Society London 145 (Publ. No. 586), 1106 Google Scholar
Ikeda, M, Hori, RS, Ikehara, M, Miyashita, R, Chino, M and Yamada, K (2018) Carbon cycle dynamics linked with Karoo-Ferrar volcanism and astronomical cycles during Pliensbachian–Toarcian (Early Jurassic). Global and Planetary Change 170, 163–71.CrossRefGoogle Scholar
Immenhauser, A, Schoene, BR, Hoffmann, R and Niedermayr, A (2016) Mollusc and brachiopod skeletal hard parts: intricate archives of their marine environment. Sedimentology 63, 159.CrossRefGoogle Scholar
Jackson, JF (1922) Sections of the Junction-Bed and contiguous deposits. Quarterly Journal of the Geological Society of London 78, 436–48.Google Scholar
Jackson, JF (1926) The Junction-Bed of the Middle and Upper Lias on the Dorset Coast. Quarterly Journal of the Geological Society of London 82, 490525.CrossRefGoogle Scholar
Jenkyns, HC (1970) Fossil manganese nodules from the west Sicilian Jurassic. Eclogae Geologicae Helvetiae 63, 741–74.Google Scholar
Jenkyns, HC (1971) The genesis of condensed sequences in the Tethyan Jurassic. Lethaia 4, 327–52.CrossRefGoogle Scholar
Jenkyns, HC (2003) Evidence for rapid climate change in the Mesozoic–Palaeogene greenhouse world. Philosophical Transactions of the Royal Society of London, Series A 361, 1885–916.CrossRefGoogle ScholarPubMed
Jenkyns, HC (2010) Geochemistry of oceanic anoxic events. Geochemistry, Geophysics, Geosystems 11, Q03004. doi: 10.1029/2009GC002788 CrossRefGoogle Scholar
Jenkyns, HC and Clayton, CJ (1986) Black shales and carbon isotopes in pelagic sediments from the Tethyan Lower Jurassic. Sedimentology 33, 87106.CrossRefGoogle Scholar
Jenkyns, HC and Clayton, CJ (1997) Lower Jurassic epicontinental carbonates and mudstones from England and Wales: chemostratigraphic signals and the early Toarcian anoxic event. Sedimentology 44, 687706.CrossRefGoogle Scholar
Jenkyns, HC, Jones, CE, Gröcke, DR, Hesselbo, SP and Parkinson, DN (2002) Chemostratigraphy of the Jurassic System: applications, limitations and implications for palaeoceanography. Journal of the Geological Society, London 159, 351–78.CrossRefGoogle Scholar
Jenkyns, HC, Schouten-Huibers, L, Schouten, S and Sinninghe Damsté, JS (2012) Warm Middle Jurassic–Early Cretaceous high-latitude sea-surface temperatures from the Southern Ocean. Climate of the Past 8, 215–26.CrossRefGoogle Scholar
Jenkyns, HC and Senior, JR (1977) A Liassic palaeofault from Dorset. Geological Magazine 114, 4752.CrossRefGoogle Scholar
Jenkyns, HC and Senior, JR (1991) Geological evidence for intra-Jurassic faulting in the Wessex Basin and its margins. Journal of the Geological Society, London 148, 245–60.CrossRefGoogle Scholar
Jenkyns, HC and Torrens, HS (1971) Palaeogeographic evolution of Jurassic seamounts in Western Sicily. In Colloque du Jurassique méditerranéen (ed. Végh-Neubrandt, E), pp. 91104. Annales Instituti Geologici Publici Hungarici 54.Google Scholar
Jones, CE, Jenkyns, HC and Hesselbo, SP (1994) Strontium isotopes in Early Jurassic seawater. Geochimica et Cosmochimica Acta 58, 1285–301.CrossRefGoogle Scholar
Kafousia, N, Karakitsios, V, Mattioli, E, Kenjo, S and Jenkyns, HC (2014) The Toarcian Oceanic Anoxic Event in the Ionian Zone, Greece. Palaeogeography, Palaeoclimatology, Palaeoecology 393, 135–45.CrossRefGoogle Scholar
Karner, GD, Lake, SD and Dewey, JF (1987) The thermal and mechanical development of the Wessex Basin, southern England. In Continental Extensional Tectonics (eds Coward, MP, Dewey, JF and Hancock, PL), pp. 517–36. Geological Society of London, Special Publication no. 28.Google Scholar
Kemp, DB, Coe, AL, Cohen, AS and Schwark, L (2005) Astronomical pacing of methane release in the Early Jurassic period. Nature 437, 396–9.CrossRefGoogle ScholarPubMed
Kemp, DB, Coe, AL, Cohen, AS and Weedon, GP (2011) Astronomical forcing and chronology of the early Toarcian (Early Jurassic) oceanic anoxic event in Yorkshire, UK. Paleoceanography 26, PA4210. doi: 10.1029/2011PA002122.CrossRefGoogle Scholar
Kemp, DB and Izumi, K (2014) Multiproxy geochemical analysis of a Panthalassic margin record of the early Toarcian oceanic anoxic event (Toyora area, Japan). Palaeogeography, Palaeoclimatology, Palaeoecology 414, 332–41.CrossRefGoogle Scholar
Kemp, DB, Selby, D and Izumi, K (2020) Direct coupling between carbon release and weathering during the Toarcian oceanic anoxic event. Geology 48, 976–80.CrossRefGoogle Scholar
King, A (2011) Fossil nautiloids from the Upper Lias (Toarcian) ‘Junction Bed’ of the Ilminster Area, Somerset. Proceedings of the Somerset Archaeological and Natural History Society 154, 249–58.Google Scholar
Klein, RT, Lohmann, KC and Thayer, CW (1996) Bivalve skeletons record sea-surface temperature and δ18O via Mg/Ca and 18O/16O ratios. Geology 24, 415–18.2.3.CO;2>CrossRefGoogle Scholar
Li, Q, McArthur, JM and Atkinson, TC (2012) Lower Jurassic belemnites as indicators of palaeo-temperature. Palaeogeography, Palaeoclimatology, Palaeoecology 315–316, 3845.CrossRefGoogle Scholar
Littler, K, Hesselbo, SP and Jenkyns, HC (2010) A carbon-isotope perturbation at the Pliensbachian–Toarcian boundary: evidence from the Lias Group, NE England. Geological Magazine 147, 181–92.CrossRefGoogle Scholar
Marshall, JD (1992) Climatic and oceanographic isotopic signals from the carbonate rock record and their preservation. Geological Magazine 129, 143–60.CrossRefGoogle Scholar
Massari, F and Westphal, H (2011) Microbialites in the Middle–Upper Jurassic Ammonitico Rosso of the Southern Alps (Italy). In Stromatolites: Interaction of Microbes with Sediments (eds Tewari, V and Seckbach, J), pp. 223–50. Dordrecht: Springer.CrossRefGoogle Scholar
McArthur, JM, Algeo, TJ, van de Schootbrugge, B, Li, Q and Howarth, RJ (2008) Basinal restriction, black shales, Re-Os dating, and the Early Toarcian (Jurassic) oceanic anoxic event. Paleoceanography 23, PA4217. doi: 10.1029/2008PA001607.CrossRefGoogle Scholar
McArthur, JM, Donovan, DT, Thirlwall, MF, Fouke, BW and Mattey, D (2000) Strontium isotope profile of the early Toarcian (Jurassic) oceanic anoxic event, the duration of ammonite biozones, and belemnite palaeotemperatures. Earth and Planetary Science Letters 179, 269–85.CrossRefGoogle Scholar
McArthur, JM, Doyle, P, Leng, MJ, Reeves, K, Williams, CT, Garcia-Sanchez, R and Howarth, RJ (2007) Testing palaeo-environmental proxies in Jurassic belemnites: Mg/Ca, Sr/Ca, Na/Ca, δ18O and δ13C. Palaeogeography, Palaeoclimatology, Palaeoecology 252, 464–80.CrossRefGoogle Scholar
McArthur, JM, Howarth, RJ and Bailey, TR (2001) Strontium isotope stratigraphy: LOWESS version 3: best fit to the marine Sr-isotope curve for 0–509 Ma and accompanying look-up table for deriving numerical age. Journal of Geology 109, 155–70.CrossRefGoogle Scholar
McArthur, JM, Page, K, Duarte, LV, Thirlwall, MF, Li, Q, Weis, R and Comas-Rengifo, MJ (2019) Sr-isotope stratigraphy (87 Sr/86Sr) of the lowermost Toarcian of Peniche, Portugal, and its relation to ammonite zonations. Newsletters on Stratigraphy 53, 297–32.CrossRefGoogle Scholar
McElwain, JC, Wade-Murphy, J and Hesselbo, SP (2005) Changes in carbon dioxide during an oceanic anoxic event linked to intrusion into Gondwana coals. Nature 435, 479–82.CrossRefGoogle ScholarPubMed
Milliman, JD (1966) Submarine lithification of carbonate sediments. Science 153, 994–7.CrossRefGoogle ScholarPubMed
Müller, T, Jurikova, H, Gutjahr, M, Tomašových, A, Schlögl, J, Liebetrau, V, Duarte, LV, Milovský, R, Mattioli, E and Pittet, B (2020) Ocean acidification during the early Toarcian extinction event: evidence from boron isotopes in brachiopods. Geology 48, 1184–8.CrossRefGoogle Scholar
Mutterlose, J, Malkoc, M, Schouten, S, Sinninghe Damsté, JS and Forster, A (2010) TEX86 and stable δ18O paleothermometry of early Cretaceous sediments: implications for belemnite ecology and paleotemperature proxy application. Earth and Planetary Science Letters 298, 286–98.CrossRefGoogle Scholar
Nieto, LM, Ruiz-Ortiz, PA, Rey, J and Benito, MI (2008) Strontium-isotope stratigraphy as a constraint on the age of condensed levels: examples from the Jurassic of the Subbetic Zone (southern Spain). Sedimentology 55, 129.Google Scholar
Pálfy, J and Smith, PL (2000) Synchrony between Early Jurassic extinction, oceanic anoxic event, and the Karoo-Ferrar flood basalt volcanism. Geology 28, 747–50.2.0.CO;2>CrossRefGoogle Scholar
Percival, LME, Witt, MLI, Mather, TA, Hermoso, M, Jenkyns, HC, Hesselbo, SP, Al-Suwaidi, AH, Storm, MS, Xu, W and Ruhl, M (2015) Globally enhanced mercury deposition during the end-Pliensbachian extinction and Toarcian OAE: a link to the Karoo–Ferrar Large Igneous Province. Earth and Planetary Science Letters 428, 267–80.CrossRefGoogle Scholar
Percival, LME, Cohen, AS, Davies, MK, Dickson, AJ, Hesselbo, SP, Jenkyns, HC, Leng, MJ, Mather, TA, Storm, MS and Xu, W (2016) Osmium isotope evidence for two pulses of increased continental weathering linked to Early Jurassic volcanism and climate change. Geology 44, 759–62.CrossRefGoogle Scholar
Prescott, DM (1988) The geochemistry and palaeoenvironmental significance of iron pisoliths and ferromanganese crusts from the Jurassic of Mallorca, Spain. Eclogae Geologicae Helvetiae 81, 387414.Google Scholar
Raven, MJ and Dickson, JAD (1989) Fir-tree zoning: an indicator of pulsed crystallization in calcite cement crystals. Sedimentary Geology 65, 249–59.CrossRefGoogle Scholar
Remírez, MN and Algeo, TJ (2020) Carbon-cycle changes during the Toarcian (Early Jurassic) and implications for regional versus global drivers of the Toarcian oceanic anoxic event. Earth-Science Reviews 209, 103283. doi: 10.1016/j.earscirev.2020.103283.CrossRefGoogle Scholar
Reolid, M (2011) Palaeoenvironmental contexts for microbial communities from Fe-Mn crusts of Middle–Upper Jurassic hardgrounds (Betic-Rifian Cordillera). Revista Española de Paleontologia 26, 135–60.Google Scholar
Rosales, I, Quesada, S and Robles, S (2004a) Paleotemperature variations of Early Jurassic seawater recorded in geochemical trends of belemnites from the Basque–Cantabrian basin, northern Spain. Palaeogeography, Palaeoclimatology, Palaeoecology 203, 253–75.CrossRefGoogle Scholar
Rosales, I, Robles, S and Quesada, S (2004b) Elemental and oxygen isotope composition of Early Jurassic belemnites: salinity vs. temperature signals. Journal of Sedimentary Research 74, 342–54.CrossRefGoogle Scholar
Rosenthal, Y, Boyle, EA and Slowey, N (1997) Temperature control on the incorporation of magnesium, strontium, fluorine, and cadmium into benthic foraminiferal shells from Little Bahama Bank: prospects for thermocline paleoceanography. Geochimica et Cosmochimica Acta 61, 3633–43.CrossRefGoogle Scholar
Ruebsam, W, Reolid, M, Sabatino, N, Masetti, D and Schwark, L (2020) Molecular paleothermometry of the early Toarcian climate perturbation. Global and Planetary Change 195, 103351. doi: 10.1016/j.gloplacha.2020.103351.CrossRefGoogle Scholar
Sabatino, N, Neri, R, Bellanca, A, Jenkyns, HC, Baudin, F, Parisi, G and Masetti, D (2009) Carbon-isotope records of the Early Jurassic (Toarcian) oceanic anoxic event from the Valdorbia (Umbria–Marche Apennines) and Monte Mangart (Julian Alps) sections: palaeoceanographic and stratigraphic implications Sedimentology 56, 1307–28.CrossRefGoogle Scholar
Sabatino, N, Vlahović, I, Jenkyns, HC, Scopelliti, G, Neri, R, Prtoljan, B and Velić, I (2013) Carbon-isotope record and palaeoenvironmental changes during the early Toarcian oceanic anoxic event in shallow-marine carbonates of the Adriatic Carbonate Platform in Croatia. Geological Magazine 150, 1085–102.CrossRefGoogle Scholar
Scopelliti, G and Russo, V (2021) Petrographic and geochemical characterization of the Middle–Upper Jurassic Fe–Mn crusts and mineralizations from Monte Inici (north-western Sicily): genetic implications. International Journal of Earth Sciences 110, 559–82.CrossRefGoogle Scholar
Sellwood, BW, Durkin, MK and Kennedy, WJ (1970) Field meeting on the Jurassic and Cretaceous rocks of Wessex. Proceedings of the Geologists’ Association 81, 715–32.CrossRefGoogle Scholar
Sellwood, BW and Jenkyns, HC (1975) Basins and swells and the evolution of an epeiric sea (Pliensbachian–Bajocian of Great Britain). Journal of the Geological Society, London 131, 373–88.CrossRefGoogle Scholar
Storm, MS, Hesselbo, SP, Jenkyns, HC, Ruhl, M, Ullmann, CV, Xu, W, Leng, MJ, Riding, JB and Gorbanenko, O (2020) Orbital pacing and secular evolution of the Early Jurassic carbon cycle. Proceedings of the National Academy of Sciences 117, 3974–82.CrossRefGoogle ScholarPubMed
Suan, G, Mattioli, E, Pittet, B, Lécuyer, C, Suchéras-Marx, B, Duarte, LV, Philippe, M, Reggiani, L and Martineau, F (2010) Secular environmental precursors to Early Toarcian (Jurassic) extreme climate changes. Earth and Planetary Science Letters 290, 448–58.CrossRefGoogle Scholar
Suan, G, Nikitenko, BL, Rogov, MA, Baudin, F, Spangenberg, JE, Knyazev, VG, Glinskikh, LA, Goryacheva, AA, Adatte, T, Riding, JB and Föllmi, KB (2011) Polar record of Early Jurassic massive carbon injection. Earth and Planetary Science Letters 312, 102–13.CrossRefGoogle Scholar
Svensen, H, Planke, S, Chevallier, L, Malthe-Sørenssen, A, Corfu, F and Jamtveit, B (2007) Hydrothermal venting of greenhouse gases triggering Early Jurassic global warming. Earth and Planetary Science Letters 256, 554–66.CrossRefGoogle Scholar
Them, TR II, Gill, BC, Caruthers, AH, Gröcke, DR, Tulsky, ET, Martindale, RC, Poulton, TP and Smith, PL (2017) High-resolution carbon isotope records of the Toarcian Oceanic Anoxic Event (Early Jurassic) from North America and implications for the global drivers of the Toarcian carbon cycle. Earth and Planetary Science Letters 459, 118–26.CrossRefGoogle Scholar
Trecalli, A, Spangenberg, J, Adatte, T, Föllmi, KB and Parente, M (2012) Carbonate platform evidence of ocean acidification at the onset of the early Toarcian oceanic anoxic event. Earth and Planetary Science Letters 357, 214–25.CrossRefGoogle Scholar
Ullmann, CV, Boyle, R, Duarte, LV, Hesselbo, SP, Kasemann, SA, Klein, T, Lenton, TM, Piazza, V and Aberhan, M (2020) Warm afterglow from the Toarcian Oceanic Anoxic Event drives the success of deep-adapted brachiopods. Scientific Reports 10, 6549. doi: 10.1038/s41598-020-63487-6.CrossRefGoogle ScholarPubMed
Ullmann, CV, Campbell, HJ, Frei, R, Hesselbo, SP, von Strandmann, PAP and Korte, C (2013a) Partial diagenetic overprint of Late Jurassic belemnites from New Zealand: implications for the preservation potential of δ7Li values in calcite fossils. Geochimica et Cosmochimica Acta 120, 8096.CrossRefGoogle Scholar
Ullmann, CV, Hesselbo, SP and Korte, C (2013b) Tectonic forcing of Early to Middle Jurassic seawater Sr/Ca. Geology 41, 1211–14.CrossRefGoogle Scholar
Ullmann, CV and Pogge von Strandmann, PA (2017) The effect of shell secretion rate on Mg/Ca and Sr/Ca ratios in biogenic calcite as observed in a belemnite rostrum. Biogeosciences 14, 8997.CrossRefGoogle Scholar
Ullmann, CV, Thibault, N, Ruhl, M, Hesselbo, SP and Korte, C (2014) Effect of a Jurassic oceanic anoxic event on belemnite ecology and evolution. Proceedings of the National Academy of Sciences 111, 10073–6.CrossRefGoogle ScholarPubMed
Vakhrameyev, VA (1982) Classopollis pollen as an indicator of Jurassic and Cretaceous climate. International Geology Review 24, 1190–6.CrossRefGoogle Scholar
Vera, JA and Martín-Algarra, A (1994) Mesozoic stratigraphic breaks and pelagic stromatolites in the Betic Cordillera, Southern Spain. In Phanerozoic Stromatolites II (eds Bertrand-Sarfati, J and Monty, C), pp. 319–44. Dordrecht: Springer.CrossRefGoogle Scholar
Wendt, J (1968) Discohelix (Archaeogastropoda, Euomphalacea) as an index fossil in the Tethyan Jurassic. Palaeontology 11, 554–75.Google Scholar
Woodfine, RG, Jenkyns, HC, Sarti, M, Baroncini, F and Violante, C (2008) The response of two Tethyan carbonate platforms to the early Toarcian (Jurassic) oceanic anoxic event: environmental change and differential subsidence. Sedimentology 55, 1011–28.CrossRefGoogle Scholar
Xu, W, Ruhl, M, Jenkyns, HC, Hesselbo, SP, Riding, JB, Selby, D, Naafs, BDA, Weijers, JW, Pancost, RD, Tegelaar, EW and Idiz, EF (2017) Carbon sequestration in an expanded lake system during the Toarcian oceanic anoxic event. Nature Geoscience 10, 129–34.CrossRefGoogle Scholar
Xu, W, Ruhl, M, Jenkyns, HC, Leng, MJ, Huggett, JM, Minisini, D, Ullmann, CV, Riding, JB, Weijers, JW, Storm, MS and Percival, LM (2018) Evolution of the Toarcian (Early Jurassic) carbon-cycle and global climatic controls on local sedimentary processes (Cardigan Bay Basin, UK). Earth and Planetary Science Letters 484, 396411.CrossRefGoogle Scholar
Supplementary material: File

Jenkyns and Macfarlane supplementary material

Jenkyns and Macfarlane supplementary material

Download Jenkyns and Macfarlane supplementary material(File)
File 119.3 KB