High resolution Sr-isotope stratigraphy of Early Cretaceous belemnites - an approach for correlating Boreal and Tethyan events
Final Report Abstract
The aims of the project were to better correlate the biostratigraphic framework of the Boreal Realm and the Tethys and to reconstruct the paleoenvironmental, paleoclimatic and paleoceanographic conditions in both areas during the Berriasian - Albian. This time interval is of special interest because of i) two positive δ13CBel events (Weissert Event, OAE 1a), ii) several potential cold snaps, iii) a long term shift from cool-humid conditions (Valanginian – Hauterivian) to a super warmhouse state (Aptian – Albian). The major results of the current project are the following: An improved 87Sr/86Sr isotope curve allows a correlation of the Berriasian - Albian (Early Cretaceous) interval of the Tethys and the Boreal Realm. The two biozonation schemes show mismatches for the base of the Hauterivian and the Barremian. - Tex86 data document a significant warming for the Boreal equivalent of the early Aptian Oceanic Anoxic Event 1a (39°N paleolatitude). These are the highest values encountered for the entire Hauterivian – Aptian interval. This warming event was associated with large igneous provinces activity. - The Early Cretaceous greenhouse was punctuated by three coldhouse episodes in the late Valanginian - earliest Hauterivian, the late early Aptian and the latest Aptian – earliest Albian. These coldhouse episodes are comparable with those of the early Maastrichtian and late Paleocene. Widespread burial of organic matter may have initiated the cooling episodes. - A first-order Early Cretaceous warming peak during the Barremian is mirrored both in the Boreal Realm and in the Tethys by the highest Sr-isotope value that we link to long-term peak continental weathering.
Publications
- 2013. Early Cretaceous chalks from the North Sea giving evidence for global change. Nature Communication
Mutterlose, J., Bottini, C.
(See online at https://doi.org/10.1038/ncomms2698) - 2014. High sea-surface temperatures during the early Aptian Oceanic Anoxic Event 1a in the Boreal Realm. Geology, 42, 5, 439-442
Mutterlose, J., Bottini, C., Schouten, S., Damste, J.S.S.
(See online at https://doi.org/10.1130/G35394.1) - 2014. Strontium-isotope stratigraphy of the Early Cretaceous (Valanginian-Barremian): Implications for Boreal-Tethys correlation and paleoclimate. Cretaceous Research, 50, 252-263
Mutterlose, J., Bodin, S., Fähnrich, L.
(See online at https://doi.org/10.1016/j.cretres.2014.03.027) - 2015. Latitudinal temperature trends in the northern hemisphere during the Early Cretaceous (Valanginian–Hauterivian). Palaeogeography, Palaeoclimatology, Palaeoecology, 424, 17-39
Meissner, P., Mutterlose, J., Bodin, S.
(See online at https://doi.org/10.1016/j.palaeo.2015.02.003) - Large igneous provinces and organic carbon burial: Controls on global temperature and continental weathering during the Early Cretaceous. Global and Planetary Change, Volume 133, October 2015, Pages 238-253
Bodin, S., Meissner, P., Janssen, N., Steuber, T., Mutterlose, J.
(See online at https://doi.org/10.1016/j.gloplacha.2015.09.001)
