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Climate and vegetation history of western Portugal inferred from Albian near-shore deposits (Galé Formation, Lusitanian Basin)

Published online by Cambridge University Press:  01 May 2012

ULRICH HEIMHOFER ,
PETER-A. HOCHULI ,
STEFAN BURLA ,
FELIX OBERLI ,
THIERRY ADATTE ,
JORGE L. DINIS  and
HELMUT WEISSERT
ULRICH HEIMHOFER*
Affiliation:
Institute of Geology, Leibniz University Hannover, 30167 Hannover, Germany
PETER-A. HOCHULI
Affiliation:
Palaeontological Institute, University of Zürich, CH-8006 Zürich, Switzerland
STEFAN BURLA
Affiliation:
Geological Institute, ETH Zürich, CH-8092 Zürich, Switzerland
FELIX OBERLI
Affiliation:
Institute of Geochemistry and Petrology, ETH Zürich, CH-8092 Zürich, Switzerland
THIERRY ADATTE
Affiliation:
Institute of Geology and Palaeontology, Université de Lausanne, CH-1015 Lausanne, Switzerland
JORGE L. DINIS
Affiliation:
Departamento de Ciências da Terra, Universidade de Coimbra, 3000 Coimbra, Portugal
HELMUT WEISSERT
Affiliation:
Geological Institute, ETH Zürich, CH-8092 Zürich, Switzerland
*
†Author for correspondence: [email protected]
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Abstract

The late Early Cretaceous greenhouse climate has been studied intensively based on proxy data derived essentially from open marine archives. In contrast, information on continental climatic conditions and on the accompanying response of vegetation is relatively scarce, most notably owing to the stratigraphic uncertainties associated with many Lower Cretaceous terrestrial deposits. Here, we present a palynological record from Albian near-shore deposits of the Lusitanian Basin of W Portugal, which have been independently dated using Sr-isotope signals derived from low-Mg oyster shell calcite. 87Sr/86Sr values fluctuate between 0.707373 ± 0.00002 and 0.707456 ± 0.00003; absolute values and the overall stratigraphic trend match well with the global open marine seawater signature during Albian times. Based on the new Sr-isotope data, existing biostratigraphic assignments of the succession are corroborated and partly revised. Spore-pollen data provide information on the vegetation community structure and are flanked by sedimentological and clay mineralogical data used to infer the overall climatic conditions prevailing on the adjacent continent. Variations in the distribution of climate-sensitive pollen and spores indicate distinct changes in moisture availability across the studied succession with a pronounced increase in hygrophilous spores in late Early Albian times. Comparison with time-equivalent palynofloras from the Algarve Basin of southern Portugal shows pronounced differences in the xerophyte/hygrophyte ratio, interpreted to reflect the effect of a broad arid climate belt covering southern and southeastern Iberia during Early Albian times.

Keywords

Albian StageSr-isotopespalynologyclay mineralogypalaeoclimatePortugal
Type
Original Articles
Information
Geological Magazine , Volume 149 , Issue 6 , November 2012 , pp. 1046 - 1064
Copyright
Copyright © Cambridge University Press 2012

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References

Abbink, O. A. 1998. Palynological Investigations in the Jurassic of the North Sea region. Ph.D. thesis, Universiteit Utrecht, The Netherlands, 192 pp. Published thesis.Google Scholar
Abbink, O. A., Van Konijnenburg-Van Cittert, J. H. A. & Visscher, H. 2004. A sporomorph ecogroup model for the Northwest European Jurassic–Lower Cretaceous: concepts and framework. Geologie en Mijnbouw 83, 17–31.Google Scholar
Adatte, T., Stinnesbeck, W. & Keller, G. 1996. Lithostratigraphic and mineralogic correlations of near K/T boundary clastic sediments in northeastern Mexico: implications for origin and nature of deposition. In The Cretaceous-Tertiary Event and Other Catastrophes in Earth History (eds Ryder, G., Fastovsky, D. E. & Gartner, S.), 211–26. Geological Society of America, Special Paper no. 307.Google Scholar
Balme, B. E. 1957. Spores and Pollen Grains From the Mesozoic of Western Australia. Commonwealth Scientific and Industrial Resarch Organisation, Australia, Coal Research Section, Reference T.C. 25, 48 pp.Google Scholar
Barrón, E., Comas-Rengifo, M. J. & Elorza, I. 2001. Contribuciones al estudio palinológico del Cretácico Inferior de la Cuenca Vasco-Cantábrica: los afloramientos ambarígenos de Peñacerrada (España). Coloquios de Paleontología 52, 135–56.Google Scholar
Berthou, P. Y., Blanc, P. & Chamley, H. 1982. Sédimentation argileuse comparée au Crétacé moyen et supérieur dans le bassin occidental portugais et sur la marge voisine (site 398 DSDP): enseignements paléogéographiques et tectoniques. Bulletin de la Société géologique de France 24, 461–72.Google Scholar
Berthou, P.-Y. & Leereveld, H. 1990. Stratigraphic implications of palynological studies on Berriasian to Albian deposits from western and southern Portugal. Review of Palaeobotany and Palynology 66, 313–44.Google Scholar
Berthou, P. Y. & Schroeder, R. 1979. Découverte d'un niveau à Simplorbitolina CIRY et RAT dans l'Albien de Guincho (région de Lisbonne, Portugal). Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences, Serie D: Sciences Naturelles 288, 591–4.Google Scholar
Bice, K. L., Birgel, D., Meyers, P. A., Dahl, K. A., Hinrichs, K.-U. & Norris, R. D. 2006. A multiple proxy and model study of Cretaceous upper ocean temperatures and atmospheric CO2 concentrations. Paleoceanography 21, PA2002, doi:10.1029/2005PA001203, 17 pp.Google Scholar
Bralower, T. J., Arthur, M. A., Leckie, R. M., Sliter, W. V., Allard, D. J. & Schlanger, S. O. 1994. Timing and paleoceanography of oceanic dysoxia/anoxia in the Late Barremian to Early Aptian (Early Cretaceous). Palaios 9, 335–69.Google Scholar
Bralower, T. J., Fullagar, P. D., Paull, C. K., Dwyer, G. S. & Leckie, R. M. 1997. Mid-Cretaceous strontium-isotope stratigraphy of deep-sea sections. Geological Society of America Bulletin 109, 1421–42.2.3.CO;2>CrossRefGoogle Scholar
Brenner, G. J. 1963. The Spores and Pollen of the Potomac Group of Maryland. Maryland Department of Geology, Mines and Water Resources Bulletin no. 27, 215 pp.Google Scholar
Brenner, G. 1976. Middle Cretaceous floral provinces and early migrations of angiosperms. In Origin and Early Evolution of Angiosperms (ed. Beck, C. B.), pp. 23–44. New York: Columbia University Press.Google Scholar
Burla, S., Oberli, F., Heimhofer, U., Wiechert, U. & Weissert, H. 2009. Improved time control on Cretaceous coastal deposits: new results from Sr isotope measurements using laser ablation. Terra Nova 21, 401–9.Google Scholar
Carter, J. G. 1990. Shell microstructural data for the Bivalvia. Part IV. Order Ostreoida. In Skeletal Biomineralization: Patterns, Processes and Evolutionary Trends (ed. Carter, J.), pp. 347–62. New York: Van Nostrand Reinhold.Google Scholar
Chamley, H. 1989. Clay Mineralogy. Berlin: Springer, 623 pp.Google Scholar
Christensen, J. N., Halliday, A. N., Lee, D.-C. & Hall, C. M. 1995. In situ Sr isotopic analysis by laser ablation. Earth and Planetary Science Letters 136, 79–85.Google Scholar
Chumakov, N. M., Zharkov, M. A., Herman, A. B., Doludenko, M. P., Kalandadze, N. M., Lebedev, E. L., Ponomarenko, A. G. & Rautian, A. S. 1995. Climatic belts of the mid-Cretaceous time. Stratigraphy and Geological Correlation 3, 241–60.Google Scholar
Clarke, L. J. & Jenkyns, H. C. 1999. New oxygen isotope evidence for long-term Cretaceous climate change in the Southern Hemisphere. Geology 27, 699–702.Google Scholar
Coiffard, C., Gomez, B. & Thevenard, F. 2007. Early Cretaceous angiosperm invasion of western Europe and major environmental changes. Annals of Botany 100, 545–53.CrossRefGoogle ScholarPubMed
Cookson, I. C. 1947. Plant microfossils from the lignites of Kerguelen Archipelago. British and New Zealand Antarctic Research Expedition, 1929–1931, Reports, series A 2, 127–42.Google Scholar
Crane, P. R., Friis, E. M. & Pedersen, K. R. 1995. The origin and early diversification of angiosperms. Nature 374, 27–33.Google Scholar
Crane, P. R. & Lidgard, S. 1989. Angiosperm diversification and paleolatitudinal gradients in Cretaceous floristic diversity. Science 246, 675–8.Google Scholar
Davies, E. H. 1985. The Anemiacean, Schizaeacean and related spores: an index to genera and species. Canadian Technical Report of Hydrography and Ocean Sciences 67. Bedford Institute of Oceanography.Google Scholar
Deák, M. H. 1962. Két új spóra gensuz az apti agyag márga sorozatbol. Földtani Közlöny 92, 230–5.Google Scholar
Deák, M. H. 1963. Quelques spores striées de l’étage Aptien. Revue de Micropaléontologie 5, 251–6.Google Scholar
Deconinck, J.-F. & Chamley, B. 1995. Diversity of smectite origins in Late Cretaceous sediments: examples of chalks from northern France. Clay Minerals 30, 365–79.CrossRefGoogle Scholar
Delcourt, A. F. & Sprumont, G. 1955. Les spores et grains de pollen du Wealdien du Hainaut. Mémories de la Société Belge de Géologie, de Paléontologie et d'Hydrologie, Nouvelle Série 5, 1–73.Google Scholar
Denison, R. E., Miller, N. R., Scott, R. W. & Reaser, D. F. 2003. Strontium isotope stratigraphy of the Comanchean Series in north Texas and southern Oklahoma. Geological Society of America Bulletin 115, 669–82.Google Scholar
Diéguez, C., Peyrot, D. & Barrón, E. 2010. Floristic and vegetational changes in the Iberian Peninsula during Jurassic and Cretaceous. Review of Palaeobotany and Palynology 162, 325–40.Google Scholar
Dinis, J. L., Rey, J., Cunha, P. P., Callapez, P. & Pena dos Reis, R. 2008. Stratigraphy and allogenic controls of the western Portugal Cretaceous: an updated synthesis. Cretaceous Research 29, 772–80.Google Scholar
Dinis, J. L., Rey, J. & de Graciansky, P. C. 2002. The Lusitanian Basin (Portugal) during the late Aptian-Albian: sequential arrangement, proposal of correlations, evolution. Comptes Rendus Geoscience 334, 757–64.Google Scholar
Dinis, J. L. & Trincão, P. 1995. Recognition and stratigraphical significance of the Aptian unconformity in the Lusitanian Basin, Portugal. Cretaceous Research 16, 171–86.Google Scholar
Doyle, J. A., Jardiné, S. & Doerenkamp, A. 1982. Afropollis, a new genus of early angiosperm pollen, with notes on the Cretaceous palynostratigraphy and palaeoenvironments of northern Gondwana. Bulletin des Centres de Recherches Exploration-Production Elf-Aquitaine 6, 39–117.Google Scholar
Doyle, J. A. & Robbins, E. I. 1977. Angiosperm pollen zonation of the continental Cretaceous of the Atlantic Coastal Plain and its application to deep wells in the Salisbury Embayment. Palynology 1, 43–78.Google Scholar
Erbacher, J., Friedrich, O., Wilson, P. A., Lehmann, J. & Weiss, W. 2011. Short-term warming events during the boreal Albian (mid-Cretaceous). Geology 39, 223–6.Google Scholar
Erbacher, J., Huber, B. T., Norris, R. D. & Markey, M. 2001. Increased thermohaline stratification as a possible cause for an ocean anoxic event in the Cretaceous period. Nature 409, 325–7.Google Scholar
Erbacher, J., Thurow, J. & Littke, R. 1996. Evolution patterns of radiolaria and organic matter variations: a new approach to identify sea-level changes in Mid-Cretaceous pelagic environments. Geology 24, 499–502.Google Scholar
Feild, T. S., Chatelet, D. S. & Brodribb, T. J. 2009. Ancestral xerophobia: a hypothesis on the whole plant ecophysiology of early angiosperms. Geobiology 7, 237–64.Google Scholar
Forster, A., Schouten, S., Baas, M. & Sinninghe Damsté, J. 2007. Mid-Cretaceous (Albian–Santonian) sea surface temperature record of the tropical Atlantic Ocean. Geology 35, 919–22.Google Scholar
Friis, E. M., Pedersen, K. R. & Crane, P. R. 2010. Cretaceous diversification of angiosperms in the western part of the Iberian Peninsula. Review of Palaeobotany and Palynology 162, 341–61.Google Scholar
Gaucher, G. 1981. Les Facteurs de la Pédogenèse. Brussels, Belgium: Dison, 730 pp.Google Scholar
Grade, J. & Moura, A. C. 1992. Estudo das formações gresosas cretácicas (Aptiano-Albiano) do flanco sul do anticlinal de Alpedriz-Porto Carro. Estudos, Notas e Trabalhos da Direcção Geral de Geologia e Minas 34, 85–94.Google Scholar
Gradstein, F. M., Ogg, J. G. & Smith, A. G. 2004. A Geologic Time Scale 2004. Cambridge: Cambridge University Press, 610 pp.Google Scholar
Groot, J. J. & Groot, C. R. 1962. Plant microfossils from Aptian, Albian and Cenomanian deposits of Portugal. Comunicações dos Serviços Geológicos de Portugal 44, 133–76.Google Scholar
Haworth, M., Hesselbo, S. P., McElwain, J. C., Robinson, S. A. & Brunt, J. W. 2005. Mid-Cretaceous pCO2 based on stomata of the extinct conifer Pseudofrenelopsis (Cheirolepidaceae). Geology 33, 749–52.Google Scholar
Hay, W. W., DeConto, R. M., Wold, C. N., Wilson, K. M., Voigt, S., Schulz, M., Rossby Wold, A., Dullo, W.-C., Ronov, A. B., Balukhovsky, A. N. & Söding, E. 1999. Alternative global Cretaceous paleogeography. In Evolution of the Cretaceous Ocean-Climate System (eds Barrera, E. & Johnson, C. C.), pp. 1–47. Geological Society of America, Special Paper no. 332.Google Scholar
Heimhofer, U., Adatte, T., Hochuli, P. A., Burla, S. & Weissert, H. 2008. Coastal sediments from the Algarve: low-latitude climate archive for the Aptian-Albian. International Journal of Earth Sciences 97, 785–97.Google Scholar
Heimhofer, U., Hochuli, P. A., Burla, S., Dinis, J. M. L. & Weissert, H. 2005. Timing of Early Cretaceous angiosperm diversification and possible links to major paleoenvironmental change. Geology 33, 141–4.Google Scholar
Heimhofer, U., Hochuli, P. A., Burla, S. & Weissert, H. 2007. New records of Early Cretaceous angiosperm pollen from Portuguese coastal deposits: implications for the timing of the early angiosperm radiation. Review of Palaeobotany and Palynology 144, 39–76.Google Scholar
Herman, A. B. & Spicer, R. A. 2010. Mid-Cretaceous floras and climate of the Russian high Arctic (Novosibirsk Islands, Northern Yakutiya). Palaeogeography, Palaeoclimatology, Palaeoecology 295, 409–22.Google Scholar
Herngreen, G. F. W. 1973. Palynology of Albian-Cenomanian strata of borehole 1-Qs-1-Ma, State of Maranhao, Brazil. Pollen et Spores 15, 515–55.Google Scholar
Herrle, J. O., Pross, J., Friedrich, O. & Hemleben, Ch. 2003. Short-term environmental changes in the Cretaceous Tethyan Ocean: micropalaeontological evidence from the Early Albian Oceanic Anoxic Event 1b. Terra Nova 15, 14–19.Google Scholar
Heusser, L. & Balsam, W. L. 1977. Pollen distribution in the Northeast Pacific Ocean. Quaternary Research 7, 45–62.Google Scholar
Hochuli, P. A. 1981. North Gondwanan floral elements in Lower to Middle Cretaceous sediments of the Southern Alps (Southern Switzerland, Northern Italy). Review of Palaeobotany and Palynology 35, 337–58.CrossRefGoogle Scholar
Hochuli, P. A., Heimhofer, U. & Weissert, H. 2006. Timing of early angiosperm radiation: recalibrating the classical succession. Journal of the Geological Society, London 163, 587–94.CrossRefGoogle Scholar
Hochuli, P. A., Os Vigran, J., Hermann, E. & Bucher, H. 2010. Multiple climatic changes around the Permian-Triassic boundary event revealed by an expanded palynological record from mid-Norway. Geological Society of America Bulletin 122, 884–96.Google Scholar
Hofmann, P., Stuesser, I., Wagner, T., Schouten, S. & Sinninghe Damsté, J. 2008. Climate-ocean coupling off North-West Africa during the Lower Albian: the Oceanic Anoxic Event 1b. Palaeogeography, Palaeoclimatology, Palaeoecology 262, 157–65.Google Scholar
Hotton, C. L. & Baghai-Riding, N. L. 2010. Palynological evidence for conifer dominance within a heterogeneous landscape in the Late Jurassic Morrison Formation, U.S.A. In Plants in Mesozoic Time: Morphological Innovations, Phylogeny, Ecosystems (ed. Gee, C. T.), pp. 295–328. Bloomington: Indianan University Press.Google Scholar
Howarth, R. J. & McArthur, J. M. 1997. Statistics for strontium isotope stratigraphy. A robust LOWESS fit to the marine Sr-isotope curve for 0–206 Ma, with look-up table for the derivation of numerical age. Geology 105, 441–56.Google Scholar
Huber, B. T., Hodell, D. A. & Hamilton, C. P. 1995. Middle-Late Cretaceous climate of the southern high latitudes: stable isotopic evidence for minimal equator-to-pole thermal gradients. Geological Society of America Bulletin 107, 1164–91.Google Scholar
Huber, B. T. & Leckie, R. M. 2011. Planktic foraminiferal species turnover across deep-sea Aptian/Albian boundary sections. Journal of Foraminiferal Research 41, 53–95.Google Scholar
Huck, S., Heimhofer, U., Rameil, N., Bodin, S. & Immenhauser, A. 2011. Strontium and carbon-isotope chronostratigraphy of Barremian-Aptian shoal-water carbonates: Northern Tethyan platform drowning predates OAE 1a. Earth and Planetary Science Letters 304, 547–58.Google Scholar
Ingram, B. L. & Sloan, D. 1992. Strontium isotopic composition of estuarine sediments as paleosalinity-paleoclimate indicator. Science 255, 68–72.Google Scholar
Jones, C. E., Jenkyns, H. C., Coe, A. L. & Hesselbo, S. P. 1994. Strontium isotopic variations in Jurassic and Cretaceous seawater. Geochimica et Cosmochimica Acta 58, 3061–74.Google Scholar
Korte, C., Kozur, H. W., Bruckschen, P. & Veizer, J. 2003. Strontium isotope evolution of Late Permian and Triassic seawater. Geochimica et Cosmochimica Acta 67, 47–62.Google Scholar
McArthur, J. M., Howarth, R. J. & Bailey, T. R. 2001. Strontium isotope stratigraphy: LOWESS Version 3. Best-fit line to the marine Sr-isotope curve for 0 to 509 Ma and accompanying look-up table for deriving numerical age. Geology 109, 155–69.Google Scholar
Medus, J. 1982. Palynofloristic correlations of two Albian sections of Portugal. Cuadernos Geología Ibérica 8, 781–809.Google Scholar
Medus, J. & Berthou, P. Y. 1980. Palynoflores dans la coupe de l'Albien de Foz do Folcao (Portugal). Geobios 13, 263–9.Google Scholar
Mendes, M. M., Dinis, J. L., Gomez, B. & Pais, J. 2010. Reassessment of the cheirolepidiaceous conifer Frenelopsis teixeirae Alvin et Pais from the Early Cretaceous (Hauterivian) of Portugal and palaeoenvironmental considerations. Review of Palaeobotany and Palynology 161, 30–42.Google Scholar
Moore, D. & Reynolds, R. 1997. X-Ray-Diffraction and the Identification and Analysis of Clay-Minerals. New York: Oxford University Press, 378 pp.Google Scholar
Pelzer, G. 1984. Cross section through fluvial environment in the Wealden of Northwest Germany. In Proceedings of the Third Symposium on Mesozoic Terrestrial Ecosystems, Tübingen, 1984, pp. 181–6.Google Scholar
Pelzer, G., Riegel, W. & Wilde, V. 1992. Depositional controls on the Lower Cretaceous Wealden coals of northwest Germany. In Controls on the Distribution and Quality of Cretaceous Coals (eds McCabe, P. J. & Parrish, J. T.), pp. 227–43. Geological Society of America, Special Paper no. 267.Google Scholar
Peyrot, D., Rodriguez-Lopez, J. P., Lassaletta, L., Meléndez, N. & Barrón, E. 2007. Contributions to the palaeoenvironmental knowledge of the Escucha Formation in the Lower Cretaceous Oliete Sub-basin, Teruel, Spain. Comptes Rendus Palevol 6, 469–81.Google Scholar
Pierce, R. L. 1961. Lower-Upper Cretaceous plant microfossils from Minnesota. Minnesota Geological Survey Bulletin 42, 1–86.Google Scholar
Poulsen, C. J., Gendaszek, A. S. & Jacob, R. L. 2003. Did the rifting of the Atlantic Ocean cause the Cretaceous thermal maximum? Geology 31, 115–18.Google Scholar
Price, G. D. 1999. The evidence and implications of polar ice during the Mesozoic. Earth-Science Reviews 48, 183–210.Google Scholar
Pucéat, E., Lécuyer, C., Sheppard, S. M. F., Dromart, G., Reboulet, S. & Grandjean, P. 2003. Thermal evolution of Cretaceous Tethyan marine waters inferred from oxygen isotope composition of fish tooth enamels. Paleoceanography 18, 7.1–7.12.Google Scholar
Rey, J. 1992. Les unités lithostratigraphiques du Crétacé inférieur de la région de Lisbonne. Comunicações dos Serviços Geológicos de Portugal 78, 103–24.Google Scholar
Rey, J. 2006. Stratigraphie séquentielle et séquences de dépôt dans le Crétacé inférieur du Basin Lusitanien. Ciências da Terra, Volume Especial 6, 1–120.Google Scholar
Rey, J., Bilotte, M. & Peybernes, B. 1977. Analyse biostratigraphique et paléontologique de l'Albien marin d'Estremadura (Portugal). Géobios 10, 369–93.Google Scholar
Rey, J. & Cugny, P. 1978. Écoséquences et paléoenvironments de l'Albien. Bulletin de la Sociéte d'Histoire Naturelle de Toulouse 113, 374–86.Google Scholar
Rey, J., de Graciansky, P. C. & Jacquin, T. 2003. Les séquences de dépôt dans le Crétacé inférieur du Bassin Lusitanien. Comunicações do Instituto Geológico e Mineiro 90, 15–42.Google Scholar
Rocha, F. & Gomes, C. 1995. Palaeoenvironment of the Aveiro region of Portugal during the Cretaceous, based on clay mineralogy. Cretaceous Research 16, 187–94.Google Scholar
Rodríguez-López, J. P., Meléndez, N., de Boer, P. L. & Soria, A. R. 2008. Aeolian sand sea development along the mid-Cretaceous western Tethyan margin (Spain): erg sedimentology and palaeoclimate implications. Sedimentology 55, 1253–92.Google Scholar
Rodríguez-López, J. P., Meléndez, N., de Boer, P. L. & Soria, A. R. 2010. The action of wind and water in a mid-Cretaceous subtropical erg-margin system close to the Variscan Iberian Massif, Spain. Sedimentology 57, 1315–56.Google Scholar
Ross, N. E. 1949. On a Cretaceous pollen and spore bearing clay deposit of Scania. Bulletin of the Geological Institute, University of Upsala 34, 25–43.Google Scholar
Ruffell, A. H. & Batten, D. J. 1990. The Barremian-Aptian arid phase in western Europe. Palaeogeography, Palaeoclimatology, Palaeoecology 80, 197–212.Google Scholar
Schneider, S., Fürsich, F. T. & Werner, W. 2009. Sr-isotope stratigraphy of the Upper Jurassic of central Portugal (Lusitanian Basin) based on oyster shells. International Journal of Earth Sciences 98, 1949–70.Google Scholar
Sewall, J. O., van de Wal, R. S. W., van der Zwan, K. J., van Oosterhout, C., Dijkstra, H. A. & Scotese, C. R. 2007. Climate model boundary conditions for four Cretaceous time slices. Climate of the Past 3, 647–57.Google Scholar
Solé da Porta, N., Querol, X., Cabanes, R. & Salas, R. 1994. Nuevas aportaciones a la palinología y paleoclimatología de la Formación Esucha (Albiense inferior-medio) en las Cubetas de Utrillas y Oliete, Cordillera Ibérica Oriental. Cuadernos Geología Ibérica 18, 203–15.Google Scholar
Srivastava, S. K. 1977. Microspores from the Fredericksburg Group (Albian of the southern United States). Paléobiologie Continentale 4, 1–119.Google Scholar
Staplin, F. L. 1982. Determination of thermal alteration index from color of exinite (pollen, spores). In How to Assess Maturation and Palaeotemperatures (ed. Staplin, F. L.), pp. 7–11. Society of Economic Paleontologists and Mineralogists.Google Scholar
Steuber, T., Rauch, M., Masse, J.-P., Graaf, J. & Malkoč, M. 2005. Low-latitude seasonality of Cretaceous temperatures in warm and cold episodes. Nature 437, 1341–4.Google Scholar
Stover, L. E. 1962. Taurocusporites, a new trilete spore genus from the Lower Cretaceous of Maryland. Micropaleontology 8, 55–9.Google Scholar
Sukh-Dev, 1961. The fossil flora of the Jabalpur Series 3. Spores and pollen grains. The Palaeobotanist 8, 43–56.Google Scholar
Taugourdeau-Lantz, J., Azéma, C., Hasenboehler, B., Masure, E. & Moron, J. M. 1982. Évolution des domaines continentaux et marins de la marge portugaise (Leg 47B, site 398 D) au cours du Crétacé: essai d'interpretation par l'analyse palynologique comparée. Bulletin de la Sociéte Géologique de France 24, 447–59.Google Scholar
Tiraboschi, D., Erba, E. & Jenkyns, H. C. 2009. Origin of rhythmic Albian black shales (Piobbico core, central Italy): calcareous nannofossil quantitative and statistical analyses and paleoceanographic reconstructions. Paleoceanography 24, 1–21.Google Scholar
Traverse, A. 2007. Paleopalynology. Dordrecht: Springer, 813 pp.Google Scholar
Trincão, P. 1990. Esporos e pólenes do Cretácico inferior (Berriasiano-Aptiano) de Portugal: paleontologia e estratigrafia. Ph.D. thesis, Universidade Nova de Lisboa, Spain, 312 pp. Published thesis.Google Scholar
Tyson, R. V. 1995. Sedimentary Organic Matter. London: Chapman & Hall, 615 pp.CrossRefGoogle Scholar
Vakhrameyev, V. A. 1982. Classopollis pollen as an indicator of Jurassic and Cretaceous climate. International Geology Review 24, 1190–6.Google Scholar
van Konijnenburg-van Cittert, J. H. A. & van der Burgh, J. 1989. The flora from the Kimmeridgian (Upper Jurassic) of Culgower, Sutherland, Scotland. Review of Palaeobotany and Palynology 61, 1–51.Google Scholar
Veizer, J., Ala, D., Azmy, K., Bruckschen, P., Buhl, D., Bruhn, F., Carden, G. A. F., Diener, A., Ebneth, S., Godderis, Y., Jasper, T., Korte, C., Pawellek, F., Podlaha, O. G. & Strauss, H. 1999. 87Sr/86Sr, δ13C and δ18O evolution of Phanerozoic seawater. Chemical Geology 161, 59–88.Google Scholar
Villanueva-Amadoz, U., Pons, D., Diez, J. B., Ferrer, J. & Sender, L. M. 2010. Angiosperm pollen grains of San Just site (Escucha Formation) from the Albian of the Iberian Range (north-eastern Spain). Review of Palaeobotany and Palynology 162, 362–81.Google Scholar
Visscher, H. & van der Zwan, W. A. 1981. Palynology of the circum-Mediterranean Triassic: phytogeographical and palaeoclimatological implications. Geologische Rundschau 70, 625–36.Google Scholar
Wagner, T., Wallmann, K., Herrle, J. O., Hofmann, P. & Stuesser, I. 2007. Consequences of moderate ~ 25,000 yr lasting emission of light CO2 into the mid-Cretaceous ocean. Earth and Planetary Science Letters 259, 200–11.Google Scholar
Watson, J. 1988. The Cheirolepidiaceae. In Origin and Evolution of the Gymnosperms (ed. Beck, C. B.), pp. 382–447. New York: Columbia University Press.Google Scholar
Watson, J. & Sincock, C. A. 1992. Bennettitales of the English Wealden. London: The Palaeontographical Society, 228 pp.Google Scholar
Wilson, P. A. & Norris, R. D. 2001. Warm tropical ocean surface and global anoxia during the mid-Cretaceous period. Nature 412, 425–8.Google Scholar
Woodhead, J., Swearer, S., Hergt, J. & Maas, R. 2005. In situ Sr-isotope analysis of carbonates by LA-MC-ICP-MS: interference corrections, high spatial resolution and an example from otolith studies. Journal of Analytical Atomic Spectrometry 20, 22–7.Google Scholar