Coevolution of sedimentary and strongly peraluminous granite phosphorus records
Coevolution of sedimentary and strongly peraluminous granite phosphorus records
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DOI：
10.1016/j.epsl.2022.117795
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发表时间：
2022-09-09
影响因子：
5.3
通讯作者：
Bucholz, Claire E.
中科院分区：
文献类型：
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作者：
Bucholz, Claire E.
磷在地表生物循环和岩浆系统中都扮演着重要的角色，前者是重要的常量营养元素，后者是富含微量元素的磷酸盐矿物的骨架。在整个地球历史中，磷在火成岩和沉积体系之间的循环对地球化学循环有着潜在的深远影响。以往的研究主要集中在火成岩中磷的贡献增加对海洋磷收支的影响。与此相反，沉积物磷丰度的变化对岩浆磷收支的影响尚未得到研究。在这里，我提出了一个汇编的磷浓度强过铝花岗岩（SPG），这是通过部分熔融的沉积岩，跨越过去类似的35亿年。最大的磷浓度的SPGs突然增加，在中生代，紧随其后的类似的，以前记录的增加，在海洋silicicocentralsediment沉积720马后沉积的磷浓度。变质，岩浆，亚固相线过程对SPG散装岩石磷浓度的影响依次考虑。较低的平均散装岩石磷浓度SPGs来自沉积前720 Ma的变质沉积岩可能反映了较低的磷浓度的变质沉积物来源。SPG汇编既证实了以前对海洋沉积记录中磷丰度的观察，又提供了一个替代档案，因为它将大量大陆架和斜坡沉积岩结合在一起。地壳磷循环的一个明显的转变是记录与沉积磷进入火成地壳，在那里它可以再次风化，并返回到海洋燃料进一步光合作用的循环开始增强。虽然磷的锆石浓度已被用来区分派生从强过铝质“S型”从metaluminous“I型”花岗岩，这里提出的结果表明，磷的浓度在SPGs有一个时间依赖性，从SPGs的锆石中的磷浓度可能随时间变化类似。(c)2022 Elsevier B.V.保留所有权利。
Phosphorus plays an important role in both surface biological cycles as a critical macronutrient and in magmatic systems as the backbone for trace element-rich phosphate minerals. Phosphorus cycling between igneous and sedimentary systems throughout Earth history has had potentially profound effects on biogeochemical cycles. Previous studies have focused on the impacts of enhanced contribution of phosphorus from igneous rocks on marine phosphorus budgets. In contrast, the effect of changing sedimentary phosphorus abundances on the phosphorus budget of magmas has not been investigated. Here I present a compilation of phosphorus concentrations in strongly peraluminous granites (SPGs), which are derived through the partial melting of sedimentary rocks, spanning the past similar to 3.5 billion years. Maximum phosphorus concentrations of SPGs increase abruptly in the Phanerozoic, closely following a similar, previously documented increase in phosphorus concentrations in marine siliciclastic sediments deposited after 720 Ma. The effect of metamorphic, magmatic, and subsolidus processes on SPG bulk-rock phosphorus concentrations are considered in turn. Lower average bulk-rock phosphorus concentrations in SPGs derived from metasedimentary rocks deposited prior to 720 Ma likely reflect lower phosphorus concentrations of their metasedimentary sources. The SPG compilation both confirms previous observations of phosphorus abundances in the marine sedimentary record and provides an alternative archive in that it integrates large volumes of continental shelf to slope sedimentary rocks. A clear shift in the crustal phosphorus cycle is documented with the initiation of enhanced recycling of sedimentary phosphorus into the igneous crust, where it can be again weathered and returned to the ocean to fuel further photosynthesis. Although phosphorus concentrations in zircon have been used to distinguish between derivation from strongly peraluminous "S-type" from metaluminous "I-type" granites, the results presented here suggest that phosphorus concentrations in SPGs have a time dependency and that phosphorus concentrations in zircon from SPGs may vary similarly in time.(c) 2022 Elsevier B.V. All rights reserved.