Assessing orbital vs. volcanic control on carbon cycle during the Early Cretaceous
- 1Univ. Rennes, Géosciences Rennes, Vandoeuvre-les-Nancy, France (mathieu.martinez@univ-rennes1.fr)
- 2Instituto de Estudios Andinos Don Pablo Groeber, CONICET & Universidad de Buenos Aires, Ciudad Universitaria, pabellón 2, 1428 Buenos Aires, Argentina
- 3Géosciences Environnement Toulouse (GET), Université Paul Sabatier Toulouse 3, CNRS UMR 5563, IRD, Toulouse, France
- 4Instituto de Investigación en Paleobiología y Geología, CONICET & Universidad de Río Negro, Sede Alto Valle, 8332 General Roca, Río Negro, Argentina
- 5IIPG, CONICET. Av. J. A. Roca 1242, General Roca, Río Negro, Argentina
- 6MARUM: Center for marine Environmental Sciences, Leobener Strasse 8, Universität Bremen, 28359 Bremen, Germany
- 7Departamento Ciencias de la Tierra, Universidad de Cádiz, CASEM, 11510 Puerto Real, Spain
- 8Departamento de Geología y CEACTEMA, Universidad de Jaén, Campus Científico-Tecnológico de Linares, 23700 Linares, Spain
- 9Departamento de Estratigrafía y Paleontología, Universidad de Granada, 18002 Granada, Spain
The interval from the Valanginian to the Barremian stages (137–121 Ma; Early Cretaceous) is punctuated by several episodes of environmental changes, accompanied by shifts in weathering intensity on the continents and changes in the Tethyan neritic carbonate production. We synthetize here the astrochronology of two recent studies performed in the Neuquén basin, Vocontian Basin and Subbetic Domain (Aguirre-Urreta et al., 2019; Martinez et al., 2020), anchored to CA-ID-TIMS U-Pb ages, which conclusions have been included in the Geologic Time Scale 2020 (Gale et al, in press). We applied this time scale to a compilation of carbon-isotope ratio from belemnites and proxies of detrital supply in the Tethyan area (Vocontian Basin and Subbetic Domain). From this compilation, we show that the episodes of environmental changes are paced by a 2.4-Myr cycle and, with a lower amplitude, a 1.2-Myr cycle. In addition, the new time scale shows the synchronicity between the Weissert Event and the Parana-Etendeka Large Igneous Province. In the series of carbon-isotope ratios measured on belemnite rostra, the amplitude of the 2.4-Myr cycle is twice higher during the Valanginian than in the Late Barremian and three times higher than in the Hauterivian and Early Barremian, suggesting that the activity of the Parana-Etendeka Large Igneous Province amplified the initial orbital forcing to trigger the environmental changes observed during the Mid-Valanginian.
Reference:
Aguirre-Urreta, B., Martinez, M., Schmitz, M., Lescano, M., Omarini, J., Tunik, M., Kuhnert, H., Concheyro, A., Rawson, P.F., Ramos, V.A., Reboulet, S., Noclin, N., Frederichs, T., Nickl, A.-L., Pälike, H., 2019. Interhemispheric radio-astrochronological calibration of the time scales from the Andean and the Tethyan areas in the Valanginian–Hauterivian (Early Cretaceous). Gondwana Research 70, 104-132. https://doi.org/10.1016/j.gr.2019.01.006.
Gale, A.S., Mutterlose, J., Batenburg, S., in press. Chapter 27: The Cretaceous Period, in: Gradstein, F.M., Ogg, J.G., Schmitz, M.D., Ogg, G.M. (Eds.) Geologic Time Scale 2020. Elsevier BV, Amsterdam, The Netherlands, pp. 1023–1086.
Martinez, M., Aguado, R., Company, M., Sandoval, J., O’Dogherty, L., 2020. Integrated astrochronology of the Barremian Stage (Early Cretaceous) and its biostratigraphic subdivisions. Global and Planetary Change 195, 103368. https://doi.org/10.1016/j.gloplacha.2020.103368.
How to cite: Martinez, M., Aguirre-Urreta, B., Lescano, M., Dera, G., Omarini, J., Tunik, M., Frederichs, T., Pälike, H., O'Dogherty, L., Aguado, R., Company, M., and Sandoval, J.: Assessing orbital vs. volcanic control on carbon cycle during the Early Cretaceous, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-11871, https://doi.org/10.5194/egusphere-egu21-11871, 2021.
