Mariana serpentinite mud volcanism exhumes subducted seamount materials: implications for the origin of life
Mariana serpentinite mud volcanism exhumes subducted seamount materials: implications for the origin of life
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DOI：
10.1098/rsta.2018.0425
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发表时间：
2020-02-21
期刊：
影响因子：
5
通讯作者：
Pomponi, Shirley
中科院分区：
文献类型：
--
作者：
Fryer, Patricia;Wheat, C. Geoffrey;Pomponi, Shirley
海山和海脊特征在汇聚板块边界的俯冲作用对覆盖板块的变形起着重要作用，并影响着地球化学循环和相关的生物过程。在马里亚纳弧前(海沟和活动火山弧之间)上的弧前地幔活动蛇纹岩和蛇纹岩泥火山作用为俯冲过程提供了窗口。在这里，我们提出：(1)首次发现目前在马里亚纳海沟内坡俯冲的未变形的白垩纪海山；(2)与太平洋板块海山和增厚的地壳有关的弧前区的垂直形变；(3)恢复的大洋钻探计划和国际海洋发现计划蛇纹岩泥石流岩芯，证实了各种太平洋板块岩石的折返，包括俯冲的礁灰岩；(4)岩芯的岩石学、地球化学和古生物资料表明，太平洋板块海山折返覆盖了更大的空间和时间范围；(5)推断与蛇纹岩泥火山作用有关的微生物群落也可从俯冲的板块海底和/或海山中发掘出来；以及(6)这些过程对生命演化的影响。本文是“地球系统中的蛇形”讨论会的一部分。
The subduction of seamounts and ridge features at convergent plate boundaries plays an important role in the deformation of the overriding plate and influences geochemical cycling and associated biological processes. Active serpentinization of forearc mantle and serpentinite mud volcanism on the Mariana forearc (between the trench and active volcanic arc) provides windows on subduction processes. Here, we present (1) the first observation of an extensive exposure of an undeformed Cretaceous seamount currently being subducted at the Mariana Trench inner slope; (2) vertical deformation of the forearc region related to subduction of Pacific Plate seamounts and thickened crust; (3) recovered Ocean Drilling Program and International Ocean Discovery Program cores of serpentinite mudflows that confirm exhumation of various Pacific Plate lithologies, including subducted reef limestone; (4) petrologic, geochemical and paleontological data from the cores that show that Pacific Plate seamount exhumation covers greater spatial and temporal extents; (5) the inference that microbial communities associated with serpentinite mud volcanism may also be exhumed from the subducted plate seafloor and/or seamounts; and (6) the implications for effects of these processes with regard to evolution of life. This article is part of a discussion meeting issue 'Serpentine in the Earth system'.