Volatile earliest Triassic sulfur cycle : A consequence of persistent low seawater sulfate concentrations and a high sulfur cycle turnover rate?
Volatile earliest Triassic sulfur cycle : A consequence of persistent low seawater sulfate concentrations and a high sulfur cycle turnover rate?
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挥发性最早的三叠纪硫循环：持续低海水硫酸盐浓度和高硫循环周转率的结果？
DOI：
10.1016/j.palaeo.2017.02.025
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Struck
中科院分区：
文献类型：
--
作者：
Schobben;Stebbins;Strauss;Struck
二叠纪末生物大灭绝（EPME）期间海洋生物多样性的减少和生态系统的破坏与广泛的海洋缺氧条件有关。在二叠-三叠纪过渡期间，海洋地球化学硫循环，微生物硫酸盐还原（MSR）和海洋溶解硫酸盐浓度的变化可以提供对海洋化学变化在地球历史上最大规模灭绝中的作用的见解。在这项研究中，我们使用Algeo等人[Algeo，T. J.，Luo，G.M.，Song，H.Y.，里昂，T.W.，坎菲尔德，D.E.，2015.海水硫酸盐浓度长期变化的重建。Biogeosciences 12，2131-2151]，对伊朗（Kuh-e-Ali Bashi和Zal剖面）和匈牙利（Balvány North和Balvány East剖面）的硫（S）同位素记录进行了研究。这种经验推导的传递函数是基于与天然水生环境中的MSR相关的硫酸盐和硫化物之间的S同位素分馏。这种分馏是由铬可还原硫（CRS）和碳酸盐相关硫酸盐（CAS）之间S同位素组成的差异所代表的，即，Δ34SCAS-CRS。我们发现，尽管区域特定的氧化还原条件下，Δ 34 SCAS-CRS表现出几乎不变的值为15-16‰，在两个研究部分。通过将我们的记录与现代海洋沉积物的Δ 34 S硫酸盐-硫化物密度分布进行比较，我们推断，孔隙水瑞利蒸馏、碳酸盐成岩作用和其他影响不太可能明显改变研究剖面中CRS和CAS之间的S同位素偏移。此外，伊朗和匈牙利剖面之间沉积状态和有机碳（OC）通量的差异排除了电子供体对MSR-S同位素分馏的主要影响，并指向一个更普遍的控制，即，MSR趋势传递函数产生了最晚二叠纪到最早三叠纪的0.6-2.8 mM的海水硫酸盐的估计，表明具有相等的S输入和输出的平衡的海洋S循环，并且在该间隔期间硫酸盐浓度没有重大变化。然而，早三叠世δ 34 SCAS（> 5‰）的长期趋势只能通过增加S旋回的周转率（约5‰）来解释。一个数量级）和伴随的变化，在陆地S源在一个盒子模型实验。具有高δ 34 S的蒸发岩沉积物的暴露可能解释了源的变化，西伯利亚圈闭火山作用可能通过寒武纪岩盐的岩浆再活化而起作用。高硫循环周转率会使海洋系统容易受到广泛的缺氧条件的发展，对早三叠世的海洋生物构成持续的威胁。
Marine biodiversity decreases and ecosystem destruction during the end-Permian mass extinction (EPME) have been linked to widespread marine euxinic conditions. Changes in the biogeochemical sulfur cycle, microbial sulfate reduction (MSR), and marine dissolved sulfate concentrations during the Permian-Triassic transition can provide insights into the role of ocean chemistry change in the largest mass extinction in Earth history. In this study, we constrain marine dissolved sulfate concentrations using the MSR-trend method of Algeo et al. [Algeo, T.J., Luo, G.M., Song, H.Y., Lyons, T.W., Canfield, D.E., 2015. Reconstruction of secular variation in seawater sulfate concentrations. Biogeosciences 12, 2131–2151] on sulfur (S) isotope records from Iran (the Kuh-e-Ali Bashi and Zal sections) and Hungary (the Bálvány North and Bálvány East sections). This empirically derived transfer function is based on the S isotope fractionation between sulfate and sulfide associated with MSR in natural aquatic environments. This fractionation is proxied by the difference in S isotope compositions between chromium-reducible sulfur (CRS) and carbonate-associated sulfate (CAS), i.e., Δ34SCAS-CRS. We show that, despite region-specific redox conditions, Δ34SCAS-CRSexhibits a nearly invariant value of 15–16‰ in both study sections. By comparing our record with a Δ34Ssulfate-sulfidedensity distribution for modern marine sediments, we deduce that porewater Rayleigh distillation, carbonate diagenesis, and other effects are unlikely to have appreciably altered the S isotope offset between CRS and CAS in the study sections. In addition, differences in sedimentary regimes and organic carbon (OC) fluxes between the Iranian and Hungarian sections exclude major influence of the electron donor on MSR-S isotope fractionation and point to a more universal control, i.e., contemporaneous seawater sulfate concentration.The MSR-trend transfer function yielded estimates of seawater sulfate of 0.6–2.8 mM for the latest Permian to earliest Triassic, suggesting a balanced oceanic S-cycle with equal S inputs and outputs and no major changes in sulfate concentrations during this interval. However, a secular trend toward heavierδ34SCAS(by > 5‰) in the earliest Triassic can be explained only by increasing the turnover rate of the S-cycle (by ca. one order of magnitude) and a concomitant change in terrestrial S sources in a box model experiment. Exposure of evaporite deposits having a highδ34S may account for the source change, with a possible role for the Siberian Traps volcanism by magmatic remobilization of Cambrian rock salt. A high sulfur cycle turnover rate would have left the ocean system vulnerable to development of widespread euxinic conditions, posing a sustained threat to marine life during the Early Triassic.
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影响因子：
1.8
作者：
L. Leda;D. Korn;A. Ghaderi;V. Hairapetian;U. Struck;W. Reimold
通讯作者：
L. Leda;D. Korn;A. Ghaderi;V. Hairapetian;U. Struck;W. Reimold
DOI：
10.1073/pnas.1503755112
发表时间：
2015-08
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
Martin Schobben;A. Stebbins;A. Ghaderi;H. Strauss;D. Korn;C. Korte
通讯作者：
Martin Schobben;A. Stebbins;A. Ghaderi;H. Strauss;D. Korn;C. Korte
影响因子：
5
作者：
Antler, Gilad;Turchyn, Alexandra V.;Sivan, Orit
通讯作者：
Sivan, Orit
影响因子：
1.4
作者：
A. Ghaderi;L. Leda;Martin Schobben;D. Korn;A. Ashouri
通讯作者：
A. Ghaderi;L. Leda;Martin Schobben;D. Korn;A. Ashouri
早侏罗世期间海洋硫酸盐浓度低和欧洲大陆海的隔离
影响因子：
5.8
作者：
Newton R
通讯作者：
Newton R