气候变化领域集成服务门户(CCPortal): Carbonate clumped isotope evidence for latitudinal seawater temperature gradients and the oxygen isotope composition of Early Cretaceous seas

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DOI	10.1016/j.palaeo.2020.109777
	Carbonate clumped isotope evidence for latitudinal seawater temperature gradients and the oxygen isotope composition of Early Cretaceous seas
	Price G.D.; Bajnai D.; Fiebig J.
发表日期	2020
ISSN	0031-0182
卷号	552
英文摘要	In this study, we investigated Early Cretaceous (Valanginian, ca. 135 million years ago) climate from subtropical to boreal palaeolatitudes. Combined carbonate clumped isotope and oxygen isotope data derived from sub-arctic, boreal, and sub-tropical fossil belemnite rostra (Mollusca: Cephalopoda) provide new palaeotemperature estimates as well as a constraint on the oxygen isotope composition of seawater. Our belemnite data reveal balmy high-latitude marine temperatures (ca. 22 °C) and warm sub-tropical temperatures (ca. 31 °C). Supplementing our clumped isotope-based temperature estimates with published TEX86 data results in a conservative reconstruction of a latitudinal temperature gradient that is reduced compared to modern conditions. We find that modelling efforts are close to reproducing tropical temperatures when high pCO2 levels are considered. Warm polar temperatures imply, however, that data-model discrepancies remain. Early Cretaceous seawater oxygen isotope values show a modern profile and are much more positive (up to 1.5‰ SMOW) than typically assumed. Based on our findings, if the positive Cretaceous seawater δ18O values are not considered, carbonate δ18O thermometry would underestimate temperatures, most acute at middle and tropical latitudes. © 2020 Elsevier B.V.
英文关键词	Belemnites; Stable isotopes; Thermometry; Valanginian
语种	英语
scopus关键词	belemnite; carbonate system; Cretaceous; isotopic composition; oxygen isotope; paleotemperature; reconstruction; seawater; subtropical region; water temperature; Belemnoidea; Cephalopoda; Mollusca
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150470
作者单位	School of Geography, Earth & Environmental Sciences, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, United Kingdom; Institute of Geosciences, Goethe University Frankfurt, Altenhöferallee 1, Frankfurt am Main, 60438, Germany; Institute of Geology and Mineralogy, University of Cologne, Zülpicher Str. 49b, Cologne, 50674, Germany
推荐引用方式 GB/T 7714	Price G.D.,Bajnai D.,Fiebig J.. Carbonate clumped isotope evidence for latitudinal seawater temperature gradients and the oxygen isotope composition of Early Cretaceous seas[J],2020,552.
APA	Price G.D.,Bajnai D.,&Fiebig J..(2020).Carbonate clumped isotope evidence for latitudinal seawater temperature gradients and the oxygen isotope composition of Early Cretaceous seas.Palaeogeography, Palaeoclimatology, Palaeoecology,552.
MLA	Price G.D.,et al."Carbonate clumped isotope evidence for latitudinal seawater temperature gradients and the oxygen isotope composition of Early Cretaceous seas".Palaeogeography, Palaeoclimatology, Palaeoecology 552(2020).