REEBOX PRO: A forward model simulating melting of thermally and lithologically variable upwelling mantle
REEBOX PRO: A forward model simulating melting of thermally and lithologically variable upwelling mantle
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REEBOX PRO：模拟热力和岩性变化的上涌地幔熔融的正演模型
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
C. Lesher
中科院分区：
文献类型：
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作者：
E. Brown;C. Lesher
在不同的边缘环境中喷发的玄武岩的成分和体积提供了其地幔源区的热、化学和动力学状态的记录。为了将玄武岩成分和体积与其地幔源区的潜在热化学和动力学状态联系起来，我们开发了 REEBOX PRO，这是一个编译的独立应用程序，可模拟包含多达五种不同岩性的被动或主动上涌地幔的绝热减压熔融。该模型使用热力学和实验约束来计算熔体成分，这些限制对含有无水橄榄岩、含水橄榄岩、方辉橄榄岩和/或硅饱和/不饱和辉石岩的均质和岩性非均质地幔源的熔化行为和矿物熔体分配行为。主要模型输出包括针对被动和主动上升流情景计算的大块玄武岩地壳的平均成分和地壳厚度。在这里，我们提出了该模型的数学公式，并将其与现有的含水熔融模型和洋中脊玄武岩形成模型进行了基准比较。我们表明，REEBOX PRO 中包含的含水和无水橄榄岩熔融模型捕获了先前模型所证明的玄武岩成分和体积的本质差异，并将全球扩张脊系统下方的环境地幔温度限制在 1319 至 1366°C 之间，具体取决于大洋中脊地幔源的相对肥力和/或含水量。我们还展示了如何在建模程序之外操纵模型输出来计算非传统熔体混合场景。这些示例凸显了 REEBOX PRO 在一系列地球动力学背景下模拟熔体生成的灵活性。
The compositions and volumes of basalts erupted in divergent margin environments provide a record of the thermal, chemical, and dynamical state of their mantle source regions. To relate basalt compositions and volumes to the underlying thermochemical and dynamical state of their mantle source regions, we have developed REEBOX PRO, a compiled stand‐alone application that simulates adiabatic decompression melting of passively or actively upwelling mantle containing up to five distinct lithologies. The model calculates melt compositions using thermodynamic and experimental constraints on the melting behaviors and mineral‐melt partitioning behavior of homogeneous and lithologically heterogeneous mantle sources containing anhydrous peridotite, hydrous peridotite, harzburgite, and/or silica‐saturated/‐undersaturated pyroxenite. Key model outputs include the mean composition and crustal thickness for the bulk basaltic crust, calculated for passive and active upwelling scenarios. Here, we present the mathematical formulations underlying the model and benchmark it against existing hydrous melting models and models for mid‐ocean ridge basalt formation. We show that the hydrous and anhydrous peridotite melting models incorporated in REEBOX PRO capture the essential differences in basalt composition and volume demonstrated by previous models, and constrain the ambient mantle beneath the global spreading ridge system to be between 1319 and 1366°C, depending on the relative fertility and/or water content of the mid‐ocean ridge mantle source. We also show how model outputs may be manipulated outside of the modeling program to calculate nontraditional melt mixing scenarios. These examples highlight the flexibility of REEBOX PRO for simulating melt generation within a range of geodynamical contexts.