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Marine Strontium Isotope Evolution at the Triassic‐Jurassic Transition Links Transient Changes in Continental Weathering to Volcanism of the Central Atlantic Magmatic Province - Heszler - 2024 - Geochemistry, Geophysics, Geosystems - Wiley …
Introduction. Strontium isotopic composition of ancient seawater can serve as a proxy for understanding the tectonic evolution of the Earth system Hodell et al 1990, Richter et al 1992, Goddéris and François 1995, Farrell et al 1995, Blum 1997, Derry and France-Lanord 1997, McCauley and DePaolo 1997, Goddéris and Veizer 2000 as well as …
Combined with the Guanzhong basin tectonic evolution, the data of Sr content, 87Sr/86Sr ratio and hot water hydrochemistry has been used to study the supply origin and flow path of deep geothermal water in the Guanzhong central region. The Sr isotope study result shows that when accepting recharge, the geothermal water in the …
The Sr isotopic composition of rivers and groundwaters in the Bengal Plain is a major contributor to the global oceanic Sr inventory. The stable strontium isotope ratios (δ88Sr) provide a new tool to identify chemical weathering reactions in terrestrial water. In this study, we investigated the spatiotemporal variations of δ88Sr in samples of river …
Rb-Sr systematics are based on the radioactive decay of the isotope 87 Rb (that today accounts for ~27% of all rubidium) to 87 Sr (~9% of all strontium) by beta decay with a half-life of approximately 49 billion years, corresponding to a Rb decay constant (λ 87 Rb) of 1.394 × 10-11 /a (Nebel et al., 2011b).A prime application of the decay scheme is …
We used a geochemical proxy, strontium isotope analysis of tooth enamel, to investigate landscape use in early hominins. We sampled a series of hominin tooth-crowns with a relatively new method ...
In terms of temporal evolution, human Sr isotopes increase with time from the Early Gravettian to the ... R. A. Strontium isotopes from the earth to the archaeological skeleton: a review. ...
The carbon and strontium isotope features of the Xiaotan section can be correlated with those from sections in Morocco, Mongolia and Siberia, and confirm a decrease in seawater 87 Sr/ 86 Sr during Cambrian Stage 1 accompanied by C-isotope oscillations, which together may assist global stratigraphic correlation of the early …
Strontium isotopes become a valuable tracer in highly saline waters, as strontium concentration can be quite high in these fluids (Table 2 and Figure 1(e)). The role of water/rock interaction and the origin and evolution of strontium isotopic signatures will be addressed in the next section.
Abstract. Samarium-neodymium and rubidium-strontium isotopic systematics, together with plausible assumptions regarding the geochemical evolution of continental crust material, have been used to ascertain the times at which segments of continental crust were formed.
Here we present a new approach to tracking the long-term evolution of the marine carbonate factory, based on the record of carbonate stable strontium isotope ratios (δ 88/86 Sr, for which δ 88/ ...
Based on sampling and strontium isotopic compositions of the Permian carbonate rock strata in the northern part of the Upper Yangtze, the Permian strontium isotope evolution curve was established.
The lithostratigraphy, strontium isotope stratigraphy, and magnetostratigraphy were analyzed throughout the whole reef sequence. ... a 972.55-m-long core from the Xisha Islands to provide a credible chronologic constraint on the carbonate platform evolution. The lithostratigraphy, strontium isotope stratigraphy, and …
Paytan et al. assembled a record of stable strontium isotopes (88 Sr and 86 Sr) ... Fig. 4 Observed evolution of the Sr system in radiogenic versus stable Sr isotope space over the past 35 Myr. Circles reflect down-core barite measurements and are color-coded by sample age, and triangles reflect the core-top measurements. ...
First published: May 1968. https://doi/10.1029/RG006i002p00175. Citations: 379. PDF. Tools. Share. Abstract. Contrasting interpretations of existing models of Sr and Pb …
Strontium isotope stratigraphy (SIS) has progressively become an efficient chemostratigraphic tool in the research and correlation of global geological events, such as global sea level fluctuations, orogeny, and paleoclimatic and paleoenvironmental changes. In this paper, 87Sr/86Sr ratios of the Triassic marine carbonate rock samples from …
Ecology, Evolution, and Systematics; Economics; Entomology; Environment and Resources; Financial Economics; Fluid Mechanics; Food Science and Technology; Genetics; Genomics and Human Genetics; Immunology; ... Strontium Isotopes in Seawater through Time, Page 1 of 1 < Previous page ...
Abstract. The 87 Sr/ 86Sr values based on brachiopods and conodonts define a nearly continuous record for the Late Permian and Triassic intervals. Minor gaps in …
Robust strontium isotope ages and laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) U-Pb dates provide critical chronological …
The first factor links oxygen and strontium isotopic evolution, the second and, and the third one the and . These three factors explain up to 79% of the total variance.
Request PDF | Evolution of strontium isotopes in seawater during the middle Miocene: New results from ODP site 758A | The Sr-87/Sr-86 ratio of seawater has increased significantly over the last 40 Ma.
Strontium isotopes ratios (87 Sr/ 86 Sr) preserved in marine limestone are another tool for global chemostratigraphy. Strontium has a long residence time in oceans, on the order of 10 6 yr, which is significantly longer than mixing time of seawater and as such, 87 Sr/ 86 Sr composition of the ocean is considered to be homogenous in the global ...
DOI: 10.1016/S0016-7037(02)01035-9 Corpus ID: 128908236; Strontium isotope evolution of Late Permian and Triassic seawater @article{Korte2003StrontiumIE, title={Strontium isotope evolution of Late Permian and Triassic seawater}, author={Christoph Korte and Heinz W. Kozur and Peter Bruckschen and J{'a}n Veizer}, …
The carbon and strontium isotope features of the Xiaotan section can be correlated with those from sections in Morocco, Mongolia and Siberia, and confirm a decrease in seawater 87Sr/86Sr during ...
Strontium and calcium concentrations and 87 Sr/ 86 Sr isotope compositions for the waters are presented in Table 1. ε Sr SW values ranged from + 20.3 to + 31.7, corresponding to a range in 87 Sr/ 86 Sr of 0.71060 to 0.71142. Strontium concentration ranged from 330 to 2698 mg/L; calcium ranged from 1810 to 35,432 mg/L.
The divergent evolution of the Sr isotope record for the Muschelkalk Sea is most likely due to its restricted nature. During the Upper Muschelkalk, an increased input of fresh water, combined with a high evaporation rate, resulted in the input of radiogenic Sr and salinities approaching those of coeval seawater.
Second, the evolution of seawater strontium isotopes through geological time reflects the changing balance between relatively radio- genic strontium derived from continental weathering ("ST/ "'Sr as 0.712 ) and relatively nonradiogenic strontium injected into the oceans by mid-ocean ridge hydrothermal fluids (^Sry "Sr as 0.703). As such, this ...
strontium isotope evolution of the global oceans is often overlooked, although it was speculated to influ-ence the seawater Sr isotopes of nearby basins (Yang et al. 2014). In this article, we ...
The strontium (Sr) isotope method can be a powerful tool in studies of chemical weathering and soil genesis, cation provenance and mobility, and the chronostratigraphic correlation of marine sediments.It is a sensitive geochemical tracer, applicable to large-scale ecosystem studies as well as to centimeter-scaled examination …
Due to its long residence times and redox insensitivity in the oceans, Sr isotopes can be used to link the Sr-seawater trend with crustal evolution (e.g. Satkoski et al., 2017).
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