Mantle degassing related to changing redox and thermal conditions during the Precambrian supercontinent cycle
Mantle degassing related to changing redox and thermal conditions during the Precambrian supercontinent cycle
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地幔脱气与前寒武纪超大陆旋回期间氧化还原和热条件的变化有关
DOI：
10.1016/j.precamres.2020.105895
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发表时间：
2020-08
影响因子：
3.8
通讯作者：
Kusky Timothy M.
中科院分区：
文献类型：
--
作者：
Wang Zhensheng;Liu Yongsheng;Zong Keqing;Lin Jie;Kusky Timothy M.
早期浅层地球的C-O-H旋回与地幔脱气和物种形成过程密切相关。这些过程受地幔的热状态和氧化还原状态的影响，在地球漫长的历史中，不同的地幔储集层的热状态和氧化还原状态发生了显著变化。然而，C-O-H岩浆挥发物的形态与不同地幔储集层中地幔热状态和氧化还原状态的时间变化之间的联系仍然难以捉摸。我们通过C-O-H岩浆挥发分的化学平衡模拟来检验这种联系，以评估其对浅层C-O-H循环和浅层地球氧化历史的影响。我们发现，与洋壳循环、核幔物质交换或原始地幔氧化还原不均质性演化有关的太古宙地幔的快速氧化可以强烈地减少火山气中还原成分(如H_2和CH_4)的比例，从而消耗更少的光合氧，导致大气氧气的净增加，并触发2.4-2.3兆镓的大氧化事件(GOE)。在GOE之后，裂谷、大洋中脊和地柱的地幔脱气变得更加氧化，从而触发了后来与超大陆解体同步的大气氧化。我们的结果支持前寒武纪大气的氧化受地幔氧化、上升流和/或脱气的影响，特别是在GOE期间。
The C-O-H cycling of the early shallow Earth is suggested to be closely related to mantle degassing and speciation processes. These processes are influenced by the mantle’s thermal and redox states, which have changed significantly in different mantle reservoirs during Earth’s protracted history. However, the link between speciation of C-O-H magmatic volatiles and the temporal changes of the mantle’s thermal and redox states in different mantle reservoirs remains elusive. We test this link through chemical equilibrium modeling of C-O-H magmatic volatiles to assess its influences on shallow C-O-H cycling and the oxidization history of the shallow Earth. We find that a rapid oxidization of Archean mantle related to recycling of oceanic crust, core-mantle material exchange, or evolution of primitive mantle redox heterogeneities can strongly reduce the fraction of reducing compositions (e.g., H2and CH4) in volcanic gases, which then consumed less photosynthetic oxygen, leading to a net increase of atmospheric oxygen and triggering the Great Oxidation Event (GOE) at 2.4–2.3 Ga. After the GOE, mantle degassing at rifts, mid ocean ridges, and plumes became more oxidizing and thus triggered later atmospheric oxidation synchronous with supercontinent breakup. Our results support that the oxidation of the atmosphere in the Precambrian was influenced by mantle oxidation, upwelling and/or degassing, especially during the GOE.
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影响因子：
2.6
作者：
Guochun Zhao;San-zhong Li;M. Sun;S. Wilde
通讯作者：
Guochun Zhao;San-zhong Li;M. Sun;S. Wilde
整个太古代板块构造运行的地质证据：太古代古板块边界的记录
影响因子：
3.3
作者：
Kusky Timothy M.;Windley Brian F.;Polat Ali
通讯作者：
Polat Ali
影响因子：
56.9
作者：
B. Wood;L. T. Bryndzia;Kathleen E. Johnson
通讯作者：
B. Wood;L. T. Bryndzia;Kathleen E. Johnson
DOI：
10.24097/wolfram.69992.data
发表时间：
1958-03
期刊：
--
影响因子：
--
作者：
F. Leiber
通讯作者：
F. Leiber
DOI：
10.1073/pnas.1818762116
发表时间：
2019-04-02
影响因子：
11.1
作者：
Ossa, Frantz Ossa;Hofmann, Axel;Bekker, Andrey
通讯作者：
Bekker, Andrey