Mineral growth in melt conduits as a mechanism for igneous layering in shallow arc plutons: mineral chemistry of Fisher Lake orbicules and comb layers (Sierra Nevada, USA)
Mineral growth in melt conduits as a mechanism for igneous layering in shallow arc plutons: mineral chemistry of Fisher Lake orbicules and comb layers (Sierra Nevada, USA)
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熔体管道中的矿物生长作为浅弧岩体中火成岩分层的机制：费希尔湖球体和梳状层的矿物化学（美国内华达山脉）
DOI：
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发表时间：
2017
影响因子：
3.5
通讯作者：
O. Müntener
中科院分区：
文献类型：
--
作者：
A. McCarthy;O. Müntener
人们提出了不同的过程来解释深成岩中的火成岩分层的多样性。为了确定浅部岩体中上升岩浆批次的侵位和结晶机制，我们研究了内华达州北方Sierra的Fisher Lake岩体中的梳状层和环状体。通过对70个单独层的矿物学和体相化学的详细研究，我们发现，梳状层和球状边缘没有显示出形成通过自组织，振荡结晶过程的证据，但代表结晶前沿原位结晶和提取的演变熔体馏分减压驱动的结晶过程中，形成斜长石为主的新月累积在毫米至米尺度。我们建议，熔体的晶体含量和岩浆系统的动力学控制的机制，负责垂直火成岩分层浅水库。当梳状层在围岩上结晶时，较高的热梯度将增加梳状分层的多样性，表现为低效的熔体提取，从而形成角闪石梳状层和捕获的磷灰石+石英饱和演化熔体分数。高An斜长石（An 90-An97.5）是费舍尔湖梳状层和圆形边缘中广泛存在的相。我们发现，冷却速率，结晶潜热和压力变化的组合可能会占浅熔体提取区的高An斜长石。
Different processes have been proposed to explain the variety of igneous layering in plutonic rocks. To constrain the mechanisms of emplacement and crystallization of ascending magma batches in shallow plutons, we have studied comb layers and orbicules from the Fisher Lake Pluton, Northern Sierra Nevada. Through a detailed study of the mineralogy and bulk chemistry of 70 individual layers, we show that comb layers and orbicule rims show no evidence of forming through a self-organizing, oscillatory crystallization process, but represent crystallization fronts resulting from in situ crystallization and extraction of evolved melt fractions during decompression-driven crystallization, forming a plagioclase-dominated cres-cumulate at the mm- to m-scale. We propose that the crystal content of the melt and the dynamics of the magmatic system control the mechanisms responsible for vertical igneous layering in shallow reservoirs. As comb layers crystallize on wall rocks, the higher thermal gradients will increase the diversity of comb layering, expressed by inefficient melt extraction, thereby forming amphibole comb layers and trapped apatite + quartz saturated evolved melt fractions. High-An plagioclase (An90–An97.5) is a widespread phase in Fisher lake comb layers and orbicule rims. We show that a combination of cooling rate, latent heat of crystallization and pressure variations may account for high-An plagioclase in shallow melt extraction zones.
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DOI：
10.1144/sp422.9
发表时间：
2015-01-01
期刊：
CHEMICAL, PHYSICAL AND TEMPORAL EVOLUTION OF MAGMATIC SYSTEMS
影响因子：
--
作者：
Caricchi, Luca;Blundy, Jon
通讯作者：
Blundy, Jon
对熔岩通量的短期变化进行成像
影响因子：
3.5
作者：
James M
通讯作者：
James M
影响因子：
3.9
作者：
O. Namur;M. Humphreys;M. Holness
通讯作者：
O. Namur;M. Humphreys;M. Holness
破解橄榄石分区密码：区分晶体生长和扩散
影响因子：
5.8
作者：
Shea, Thomas;Lynn, Kendra J.;Garcia, Michael O.
通讯作者：
Garcia, Michael O.
DOI：
10.1144/sp422.11
发表时间：
2015-01-01
期刊：
CHEMICAL, PHYSICAL AND TEMPORAL EVOLUTION OF MAGMATIC SYSTEMS
影响因子：
--
作者：
Caricchi, Luca;Blundy, Jon
通讯作者：
Blundy, Jon