Oxygen consumption rates in subseafloor basaltic crust derived from a reaction transport model
Oxygen consumption rates in subseafloor basaltic crust derived from a reaction transport model
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DOI：
10.1038/ncomms3539
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发表时间：
2013-09
影响因子：
16.6
通讯作者：
B. Orcutt;C. Wheat;O. Rouxel;S. Hulme;K. Edwards;W. Bach
中科院分区：
文献类型：
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作者：
B. Orcutt;C. Wheat;O. Rouxel;S. Hulme;K. Edwards;W. Bach
洋壳是地球上最大的潜在生命栖息地，可能含有地球微生物生物量总量的很大一部分;然而，缺乏对玄武岩地壳反应速率的经验分析。在这里，我们报告了对年轻（~8 Ma）和凉爽（<25 °C）玄武岩地壳中氧消耗的首次评估，我们通过模拟在综合大洋钻探计划远征336期间收集的基底沉积物中的溶解氧和锶孔隙水梯度来计算，以中大西洋海岭西侧的“北池”。溶解氧在沉积柱的上段至中段被完全消耗，朝向沉积物-基底界面浓度增加，表明地壳内循环的含氧流体向上供应。上基底氧行为的参数反应输运模型表明，在年轻和凉爽的玄武质地壳中，氧的消耗速率为1 nmol cm−3ROCKd− 1或更低。
Oceanic crust is the largest potential habitat for life on Earth and may contain a significant fraction of Earth’s total microbial biomass; yet, empirical analysis of reaction rates in basaltic crust is lacking. Here we report the first assessment of oxygen consumption in young (~8 Ma) and cool (<25 °C) basaltic crust, which we calculate from modelling dissolved oxygen and strontium pore water gradients in basal sediments collected during Integrated Ocean Drilling Program Expedition 336 to ‘North Pond’ on the western flank of the Mid-Atlantic Ridge. Dissolved oxygen is completely consumed within the upper to middle section of the sediment column, with an increase in concentration towards the sediment–basement interface, indicating an upward supply from oxic fluids circulating within the crust. A parametric reaction transport model of oxygen behaviour in upper basement suggests oxygen consumption rates of 1 nmol cm−3ROCKd−1or less in young and cool basaltic crust.