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4. The Jurassic Period

Author

Hesselbo, S.P., primary, Ogg, J.G., additional, Ruhl, M., additional, Hinnov, L.A., additional, and Huang, C.J., additional

Published
2020
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7. New age constraints on the Lower Jurassic Pliensbachian–Toarcian Boundary at Chacay Melehue (Neuquén Basin, Argentina)

Author

Al-Suwaidi, A.H., Ruhl, M., Jenkyns, H.C., Damborenea, S.E., Manceñido, M.O., Condon, D.J., Angelozzi, G.N., Kamo, S.L., Storm, M., Riccardi, A.C., Hesselbo, S.P., Al-Suwaidi, A.H., Ruhl, M., Jenkyns, H.C., Damborenea, S.E., Manceñido, M.O., Condon, D.J., Angelozzi, G.N., Kamo, S.L., Storm, M., Riccardi, A.C., and Hesselbo, S.P.

Abstract

The Pliensbachian–Toarcian boundary interval is characterized by a ~ 3‰ negative carbon-isotope excursion (CIE) in organic and inorganic marine and terrestrial archives from sections in Europe, such as Peniche (Portugal) and Hawsker Bottoms, Yorkshire (UK). A new high-resolution organic-carbon isotope record, illustrating the same chemostratigraphic feature, is presented from the Southern Hemisphere Arroyo Chacay Melehue section, Chos Malal, Argentina, corroborating the global significance of this disturbance to the carbon cycle. The negative carbon-isotope excursion, mercury and organic-matter enrichment are accompanied by high-resolution ammonite and nannofossil biostratigraphy together with U–Pb CA-ID-TIMS geochronology derived from intercalated volcanic ash beds. A new age of ~ 183.73 + 0.35/− 0.50 Ma for the Pliensbachian–Toarcian boundary, and 182.77 + 0.11/− 0.15 for the tenuicostatum–serpentinum zonal boundary, is assigned based on high-precision U–Pb zircon geochronology and a Bayesian Markov chain Monte Carlo (MCMC) stratigraphic age model.

Published
2022

9. First record of the Early Toarcian Oceanic Anoxic Event from the Southern Hemisphere, Neuquen Basin, Argentina

Author

Al-Suwaidi, A.H., Angelozzi, G.N., Baudin, F., Damborenea, S.E., Hesselbo, S.P., Jenkyns, H.C., Mancenido, M.O., and Riccardi, A.C.

Subjects
Neuquen, Argentina (Province) -- Environmental aspects, Southern Hemisphere -- Environmental aspects, Basins (Geology) -- Environmental aspects, Ocean-atmosphere interaction -- Research, Earth sciences
Abstract

The first record of the Early Toarcian Oceanic Anoxic Event (c. 183 Ma) from the Southern Hemisphere is described from the Neuquen Basin, Argentina, identified chemostratigraphically on the basis of a relative increase in marine organic carbon and a characteristic negative carbon-isotope excursion ([[delta].sup.13][C.sub.org]) in bulk rock and fossil wood. The negative excursion of -6 [per thousand] in bulk organic carbon (falling to -31.3 [per thousand]) crosses the boundary of the tenuicostatum--hoelderi Andean ammonite Zones, equivalent to the tenuicostatum--falciferum/serpentinum zones of Europe. These data indicate that the Early Toarcian Oceanic Anoxic Event was a global phenomenon. Supplementary material: A detailed stratigraphic log, chemostratigraphic data and nannofossil data are available at http:// www.geolsoc.org.uk/SUP18411. doi: 10.1144/0016-76492010-025.

Published
2010

11. Discussion on a sequence-stratigraphic interpretation of a mudstone-dominated succession: the Lower Jurassic Cleveland Ironstone Formation, UK

Author

Hesselbo, S.P.

Subjects
United Kingdom -- Natural history, Geology, Stratigraphic -- Jurassic, Geologists -- Criticism and interpretation, Earth sciences
Abstract

J.H.S. Macquaker and K.G. Taylor's discussion of the presence of sediment microfabrics at the Lower Jurassic Cleveland Ironstone Formation and their conclusion regarding sequence stratigraphy require a closer examination. Some samples are not convincing and susceptible to bias due to their small size and number. However, the petrographic approach suggested by Taylor and Macquaker deserve a more extensive analysis to substantiate some of their claims.

Published
1997

16. Osmium isotope evidence for two pulses of increased continental weathering linked to Early Jurassic volcanism and climate change

Author

Percival, L.M.E., Cohen, A.S., Davies, M.K., Hesselbo, S.P., Jenkyns, H.C., Leng, Melanie J., Mather, T.A., Storm, M.S., and Xu, W.

Abstract

Large igneous provinces (LIPs) are proposed to have caused a number of episodes of abrupt environmental change by increasing atmospheric CO2 levels, which were subsequently alleviated by drawdown of CO2 via enhanced continental weathering and burial of organic matter. Here the sedimentary records of two such episodes of environmental change, the Toarcian oceanic anoxic event (T-OAE) and preceding Pliensbachian–Toarcian (Pl-To) event (both possibly linked to the Karoo-Ferrar LIP), are investigated using a new suite of geochemical proxies that have not been previously compared. Stratigraphic variations in osmium isotope (187Os/188Os) records are compared with those of mercury (Hg) and carbon isotopes (d13C) in samples from the Mochras core, Llanbedr Farm, Cardigan Bay Basin, Wales. These sedimentary rocks are confirmed as recording an open-marine setting by analysis of molybdenum/uranium enrichment trends, indicating that the Os isotope record in these samples reflects the isotopic composition of the global ocean. The Os isotope data include the first results across the Pl-To boundary, when seawater 187Os/188Os increased from ~0.40 to ~0.53, in addition to new data that show elevated 187Os/188Os (from ~0.42 to ~0.68) during the T-OAE. Both increases in 187Os/188Os correlate with negative carbon isotope excursions and increased mercury concentrations, supporting an interplay between terrestrial volcanism, weathering, and climate that was instrumental in driving these distinct episodes of global environmental change. These observations also indicate that the environmental impact of the Karoo-Ferrar LIP was not limited solely to the T-OAE.

Published
2016

19. Mochras borehole revisited: a new global standard for Early Jurassic earth history

Author

Hesselbo, S.P., Bjerum, C.J., Hinnov, L.A., MacNiocaill, C., Miller, K.G., Riding, J.B., van de Schootbrugge, B., Abels, H.A., Belcher, C., Blau, J., Browning, J., Cartwright, J., Condon, D., Daines, S., Damborenea, S., Dickson, A., Fraguas, A., Hilgen, F., Hooker, J., Huang, C., Hüsing, S., Jenkyns, H., Korte, C., Krijgsman, W., Lenton, T., Little, C., Manceñido, M., Mattioli, E., Meister, C., Morgan, R., Newton, R., Pálfy, J., Pienkowski, G., Poulton, S., Riccardi, A., Robinson, A., Ruhl, M., Suan, G., Smith, N., Thibault, N., Ullmann, C., Wignall, P., Williford, K., Wonik, T., Xu, W., Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, Stratigraphy and paleontology, Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, and Stratigraphy and paleontology

Subjects
Total organic carbon, Extinction event, Series (stratigraphy), Environmental change, Mechanical Engineering, Earth science, lcsh:QE1-996.5, Oceanografía, Hidrología, Recursos Hídricos, Borehole, Energy Engineering and Power Technology, Biota, STRATIGRAPHY, EARLY JURASSIC, BOREHOLE, Ciencias de la Tierra y relacionadas con el Medio Ambiente, lcsh:Geology, purl.org/becyt/ford/1 [https], purl.org/becyt/ford/1.5 [https], Paleontology, Stratigraphy, DRILLING, Glacial period, Geology, CIENCIAS NATURALES Y EXACTAS, GLOBAL STANDARD
Abstract

The Early Jurassic epoch was a time of extreme environmental change: there are well-documented examples of rapid transitions from cold, or even glacial, climates to super greenhouse events, the latter characterized worldwide by hugely enhanced organic carbon burial, multiple large isotopic anomalies, global sea-level change, and mass extinction (Price, 1999; Hesselbo et al., 2000; Jenkyns, 2010; Korte and Hesselbo, 2011). These icehouse–greenhouse events not only reflect changes in the global climate system but are also thought to have had significant influence on the evolution of Jurassic marine biota (e.g. van de Schootbrugge et al., 2005; Fraguas et al., 2012). Furthermore, the events may serve as analogues for present-day and future environmental transitions. Although our knowledge of specific global change events within the Early Jurassic is rapidly improving, such as the Toarcian oceanic anoxic event (or T-OAE), we still do not have a comprehensive understanding of the timing, pacing, or triggers for these environmental perturbations, principally because of the temporally fragmentary nature of the existing data sets. The major goal for this proposed ICDP project is therefore to produce a new global standard for these key 25 million years of earth history by re-drilling and doublecoring a 45 yr old borehole at Mochras Farm on the edge of Cardigan Bay, Wales, and developing an integrated stratigraphy for the cored material. The new data sets will be applied to understand fundamental questions about the longand short-term evolution of the earth system. Cycles that occur regionally and that provisionally appear in the Mochras logs will allow evaluation of the extent to which major environmental change events are astronomically forced, resulting from internal system dynamics, or are triggered by deepearth processes. Fil: Hesselbo, S. P.. University Of Exeter; Reino Unido Fil: Bjerrum, C. J.. Universidad de Copenhagen; Dinamarca Fil: Hinnov, L. A.. University Johns Hopkins; Estados Unidos Fil: Mac Niocaill, C.. University of Oxford; Reino Unido Fil: Miller, K. G.. State University of New Jersey; Estados Unidos Fil: Riding, J. B.. British Geological Survey; Reino Unido Fil: Van de Schootbrugge, B.. University of Utrecht; Países Bajos Fil: Abels, H.. The Mochras Revisited Science Team; Reino Unido Fil: Belcher, C.. The Mochras Revisited Science Team; Reino Unido Fil: Blau, J.. The Mochras Revisited Science Team; Reino Unido Fil: Browning, J.. The Mochras Revisited Science Team; Reino Unido Fil: Cartwright, J.. The Mochras Revisited Science Team; Reino Unido Fil: Condon, D.. The Mochras Revisited Science Team; Reino Unido Fil: Daines, S.. The Mochras Revisited Science Team; Reino Unido Fil: Damborenea, S.. The Mochras Revisited Science Team; Reino Unido Fil: Dickson, A.. The Mochras Revisited Science Team; Reino Unido Fil: Fraguas, A.. The Mochras Revisited Science Team; Reino Unido Fil: Hilgen, F.. The Mochras Revisited Science Team; Reino Unido Fil: Hooker, J.. The Mochras Revisited Science Team; Reino Unido Fil: Huang, C.. The Mochras Revisited Science Team; Reino Unido Fil: Huesing, S.. The Mochras Revisited Science Team; Reino Unido Fil: Jenkyns, H.. The Mochras Revisited Science Team; Reino Unido Fil: Korte, C.. The Mochras Revisited Science Team; Reino Unido Fil: Krijgsman, W.. The Mochras Revisited Science Team; Reino Unido Fil: Lenton, T.. The Mochras Revisited Science Team; Reino Unido Fil: Little, C.. The Mochras Revisited Science Team; Reino Unido Fil: Manceñido, Miguel Oscar. The Mochras Revisited Science Team; Reino Unido. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Mattioli, E.. The Mochras Revisited Science Team; Reino Unido Fil: Meister, C.. The Mochras Revisited Science Team; Reino Unido Fil: Morgan, R.. The Mochras Revisited Science Team; Reino Unido Fil: Newton, R.. The Mochras Revisited Science Team; Reino Unido Fil: Pálfy, J.. The Mochras Revisited Science Team; Reino Unido Fil: Pienkowski, G.. The Mochras Revisited Science Team; Reino Unido Fil: Poulton, S.. The Mochras Revisited Science Team; Reino Unido Fil: Riccardi, A.. The Mochras Revisited Science Team; Reino Unido Fil: Robinson, A.. The Mochras Revisited Science Team; Reino Unido Fil: Ruhl, M.. The Mochras Revisited Science Team; Reino Unido Fil: Suan, G.. The Mochras Revisited Science Team; Reino Unido Fil: Smith, N.. The Mochras Revisited Science Team; Reino Unido Fil: Thibault, N.. The Mochras Revisited Science Team; Reino Unido Fil: Ullmann, C.. The Mochras Revisited Science Team; Reino Unido Fil: Wignall, P.. The Mochras Revisited Science Team; Reino Unido Fil: Williford, K.. The Mochras Revisited Science Team; Reino Unido Fil: Wonik, T.. The Mochras Revisited Science Team; Reino Unido Fil: Xu, W.. The Mochras Revisited Science Team; Reino Unido

Published
2013
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20. Mochras borehole revisited: A new global standard for Early Jurassic Earth history

Author

Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, Stratigraphy and paleontology, Hesselbo, S.P., Bjerum, C.J., Hinnov, L.A., MacNiocaill, C., Miller, K.G., Riding, J.B., van de Schootbrugge, B., Abels, H.A., Belcher, C., Blau, J., Browning, J., Cartwright, J., Condon, D., Daines, S., Damborenea, S., Dickson, A., Fraguas, A., Hilgen, F., Hooker, J., Huang, C., Hüsing, S., Jenkyns, H., Korte, C., Krijgsman, W., Lenton, T., Little, C., Manceñido, M., Mattioli, E., Meister, C., Morgan, R., Newton, R., Pálfy, J., Pienkowski, G., Poulton, S., Riccardi, A., Robinson, A., Ruhl, M., Suan, G., Smith, N., Thibault, N., Ullmann, C., Wignall, P., Williford, K., Wonik, T., Xu, W., Marine Palynology, NWO-VENI: Middle Miocene global cooling: climate change through gateway closure, NWO-VENI: Terrestrial climate change and river floodplain dynamics during extreme greenhouse conditions in the Early Eocene, NWO-VICI: The evolution of the Paratethys: the lost sea of Central Eurasia, Paleomagnetism, Stratigraphy & paleontology, Marine palynology and palaeoceanography, Stratigraphy and paleontology, Hesselbo, S.P., Bjerum, C.J., Hinnov, L.A., MacNiocaill, C., Miller, K.G., Riding, J.B., van de Schootbrugge, B., Abels, H.A., Belcher, C., Blau, J., Browning, J., Cartwright, J., Condon, D., Daines, S., Damborenea, S., Dickson, A., Fraguas, A., Hilgen, F., Hooker, J., Huang, C., Hüsing, S., Jenkyns, H., Korte, C., Krijgsman, W., Lenton, T., Little, C., Manceñido, M., Mattioli, E., Meister, C., Morgan, R., Newton, R., Pálfy, J., Pienkowski, G., Poulton, S., Riccardi, A., Robinson, A., Ruhl, M., Suan, G., Smith, N., Thibault, N., Ullmann, C., Wignall, P., Williford, K., Wonik, T., and Xu, W.

Published
2013

21. Mochras Revisited: A New Global standard for Early Jurassic Earth History

Author

Hesselbo, S.P., Bjerrum, Christian J., Hinnov, Linda, MacNiocaill, C., Miller, K., Riding, J.B., van de Schootbrugge, B., Korte, Christoph, and the Mochras Revisited Science Team, Hesselbo, S.P., Bjerrum, Christian J., Hinnov, Linda, MacNiocaill, C., Miller, K., Riding, J.B., van de Schootbrugge, B., Korte, Christoph, and and the Mochras Revisited Science Team

Published
2013

23. Thallium isotopes in early diagenetic pyrite - A paleoredox proxy?

Author

General geochemistry, Geochemistry, Nielsen, S.G., Goff, M., Hesselbo, S.P., Jenkyns, H.C., LaRowe, D.E., Lee, C.T.A., General geochemistry, Geochemistry, Nielsen, S.G., Goff, M., Hesselbo, S.P., Jenkyns, H.C., LaRowe, D.E., and Lee, C.T.A.

Published
2011

34. Cenozoic stratigraphy and subsidence history of the South China Sea margin in the Taiwan region.

Author

Lin, A.T., Watts, A.B., and Hesselbo, S.P.

Subjects
CENOZOIC stratigraphic geology, SEQUENCE stratigraphy
Abstract

Seismic reflection profiles and well data are used to determine the Cenozoic stratigraphic and tectonic development of the northern margin of the South China Sea. In the Taiwan region, this margin evolved from a Palaeogene rift to a latest Miocene–Recent foreland basin. This evolution is related to the opening of the South China Sea and its subsequent partial closure by the Taiwan orogeny. Seismic data, together with the subsidence analysis of deep wells, show that during rifting (∼58–37 Ma), lithospheric extension occurred simultaneously in discrete rift belts. These belts form a >200 km wide rift zone and are associated with a stretching factor, β, in the range ∼1.4–1.6. By ∼37 Ma, the focus of rifting shifted to the present-day continent–ocean boundary off southern Taiwan, which led to continental rupture and initial seafloor spreading of the South China Sea at ∼30 Ma. Intense rifting during the rift–drift transition (∼37–30 Ma) may have induced a transient, small-scale mantle convection beneath the rift. The coeval crustal uplift (Oligocene uplift) of the previously rifted margin, which led to erosion and development of the breakup unconformity, was most likely caused by the induced convection. Oligocene uplift was followed by rapid, early post-breakup subsidence (∼30–18 Ma) possibly as the inferred induced convection abated following initial seafloor spreading. Rapid subsidence of the inner margin is interpreted as thermally controlled subsidence, whereas rapid subsidence in the outer shelf of the outer margin was accompanied by fault activity during the interval ∼30–21 Ma. This extension in the outer margin ( β∼1.5) is manifested in the Tainan Basin, which formed on top of the deeply eroded Mesozoic basement. During the interval ∼21–12.5 Ma, the entire margin experienced broad thermal subsidence. It was not until ∼12.5 Ma that rifting resumed, being especially active in the Tainan Basin ( β∼1.1). Rifting ceased at ∼6.5 Ma due to the orogeny caused by the overthrusting of the Luzon volcanic arc. The Taiwan orogeny created a foreland basin by loading and flexing the underlying rifted margin. The foreland flexure inherited the mechanical and thermal properties of the underlying rifted margin, thereby dividing the basin into north and south segments. The north segment developed on a lithosphere where the major rift/thermal event occurred ∼58–30 Ma, and this segment shows minor normal faulting related to lithospheric flexure. In contrast, the south segment developed on a lithosphere, which experienced two more recent rift/thermal events during ∼30–21 and ∼12.5–6.5 Ma. The basal foreland surface of the south segment is highly faulted, especially along the previous northern rifted flank, thereby creating a deeper foreland flexure that trends obliquely to the strike of the orogen. [ABSTRACT FROM AUTHOR]

Published
2003
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35. Reworked early diagenic concretions and the bioerosion origin of a regional discontinuity within British Jurassic marine mudstones.

Author

Hesselbo, S.P. and Palmer, T.J.

Subjects
*STRATIGRAPHIC geology, *EROSION
Abstract

The Coinstone is a well known hiatus-concretion level in the Lower Lias (Lower Jurassic, Upper Sinemurian) of Dorset, southern England. It has long been recognized as a layer of bored and encrusted, early diagenetic, clay-hosted septarian concretions coincident with a biostratigraphic gap of three ammonite subzones. Several different types of concretion of variable complexity can be distinguished, of which two, probably derived from slightly different stratigraphic levels, have been juxtaposed by condensation at the erosion surface. Diagenetic and biological processes occurring before, during and after exhumation on the Jurassic sea-floor can be recognized. The relative timing of these events can be distinguished, suggesting that initial concretion consolidation, the first generation of septarian cracking, and the precipitation of the first generation of crack-lining calcite preceded exhumation. These, therefore, probably took place at an early stage, at shallow burial depths within the accumulating sediment pile. The early calcite is brown, UV-fluorescent and inclusion-rich, and is similar to the first calcite generations seen in many other clay-hosted septarian concretions. A generally early diagnetic origin of this material is thus inferred. Observations on crack textures and geometries and the interactions of the post-exhumation fauna of encrusters, borers and burrowers lend support to previous suggestions that initial cracking in some septarian concretions took place in a stiff rather than a fully rigid concretion body, possibly given coherence by initial growth of some organic substance that was only later replaced by the calcite cements seen in most such concretions today. The burrowing activities of a benthic fauna in muds cause resuspension of sediment and facilitate erosion, even in the absence of high energy physical processes. Regional stratigraphic gaps may/be formed as a consequente of sea level rises or falls, or as a response to sediment... [ABSTRACT FROM AUTHOR]

Published
1992
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