Interaction of carbonates with peridotite containing iron metal: Implications for carbon speciation in the upper mantle
Interaction of carbonates with peridotite containing iron metal: Implications for carbon speciation in the upper mantle
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碳酸盐与含铁金属橄榄岩的相互作用：对上地幔碳形态的影响
DOI：
10.1016/j.lithos.2022.106817
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发表时间：
2022
期刊：
影响因子：
3.5
通讯作者：
Yoshino T.
中科院分区：
文献类型：
--
作者：
Martirosyan N.S.;Shatskiy A.;Litasov K.D.;Sharygin I.S.;Yoshino T.
由于约250公里以下地幔条件的显著降低，俯冲大洋板块输送的碳酸盐将不可避免地与含铁的地幔橄榄岩相互作用，形成钻石或其他还原碳物种。在这项研究中，我们提供了碳酸盐和橄榄岩与铁在6和10 GPa1100-1400°С下的反应实验，以模拟还原地幔中俯冲碳酸盐的行为。镁橄榄石(MWs)、铁方镁石、亚稳态石墨或金刚石结晶发生了氧化还原反应。在含钙碳酸盐和含白云石的体系中，在1100℃和1200℃已经出现了碳酸盐熔体。熔体的形成表明，在热俯冲带条件下，即使在无水和无碱体系中，含铁地幔橄榄岩和含碳酸盐俯冲岩之间的氧化还原梯度也可以引发深部地幔熔融。在氧化还原反应中形成的碳酸盐熔体和氧化物将进一步与橄榄石、辉石和石榴石相互作用，形成辉石、富钙石榴石和富铁橄榄石。动力学计算表明，在碳酸盐和铁被硅酸盐介质分离的自然体系中，由于硅酸盐中缓慢的化学扩散速度，氧化还原反应是有限的，在无水和无熔体的环境中，氧化还原反应不会对碳酸盐的保存产生任何重大影响。相反，在碳酸盐与金属铁反应过程中，碳酸盐熔体的存在将导致碳酸盐的大量消耗。
Due to the significantly reduced conditions in the mantle below ~250 km, carbonates transported by the subducting oceanic plates will inevitably interact with Fe-saturated mantle peridotites to form diamonds or other reduced carbon species. In this study, we present the reaction experiments at 6 and 10 GPa, and 1100–1400°С between carbonates and peridotite with iron to model the behaviors of subducted carbonates in the reduced mantle.Magnesiowüstite (Mws), ferropericlase, metastable graphite, or diamond crystallization showed the occurrence of the redox reactions. The reactions in Ca‑carbonate and dolomite-containing systems were accompanied by the appearance of carbonate melt already at 1100 and 1200 °C. Formation of the melt at such a low temperature in the studied systems shows that the redox gradient between iron-containing mantle peridotites and carbonate-containing subduction lithologies could trigger deep mantle melting at the hot subduction zone conditions, even in the anhydrous and alkali-free systems. Carbonate melts, and oxides, formed in the redox reactions, would further interact with olivine, pyroxenes, and garnet with the formation of merwinite, Ca-rich garnet, and Fe-rich olivine. Here we confirm that merwinite could be an indicator of the mantle metasomatism and may originate via interaction of Ca-rich carbonate melt with peridotite.The kinetic calculations reflect that, in natural systems where carbonates and iron are separated by silicate media, the redox reactions are limited due to slow chemical diffusion rates in silicates and will not have any significant effect on the preservation of carbonates in the anhydrous and melt free environment. On the contrary, the presence of carbonate melt during the reaction between carbonate and metallic Fe will lead to significant consumption of carbonates.
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影响因子：
3.7
作者：
Lobanov, Sergey S.;Dong, Xiao;Goncharov, Alexander F.
通讯作者：
Goncharov, Alexander F.
高压下氯化物-碳酸盐-硅酸盐体系的熔融关系以及上地幔中碱性金刚石形成液体的形成模型
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
O. Safonov;L. Perchuk;Y. Litvin
通讯作者：
Y. Litvin
3 GPa 和 6 GPa 下 CaCO3-MgCO3 相图的修订
影响因子：
3.1
作者：
A. Shatskiy;I. Podborodnikov;A. Arefiev;Daniil A. Minin;A. Chanyshev;K. Litasov
通讯作者：
K. Litasov
CO 2 流体和碳酸盐-硅酸盐熔体存在下的方铁矿稳定性：对石墨/金刚石形成和富铁地幔交代剂生成的影响
影响因子：
3.5
作者：
Y. Bataleva;Y. Palyanov;A. Sokol;Y. Borzdov;Oleg A. Bayukov
通讯作者：
Oleg A. Bayukov
影响因子：
1.1
作者：
Lavrent'ev, Yu. G.;Karmanov, N. S.;Usova, L. V.
通讯作者：
Usova, L. V.