Understanding Degassing and Transport of CO2-rich Alkalic Magmas at Ross Island, Antarctica using Olivine-Hosted Melt Inclusions
Understanding Degassing and Transport of CO2-rich Alkalic Magmas at Ross Island, Antarctica using Olivine-Hosted Melt Inclusions
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利用橄榄石熔融包裹体了解南极洲罗斯岛富含二氧化碳的碱性岩浆的脱气和传输
DOI：
10.1093/petrology/egx036
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发表时间：
2017
影响因子：
3.9
通讯作者：
Phillips, Erin H.
中科院分区：
文献类型：
--
作者：
Rasmussen, Daniel J.;Kyle, Philip R.;Wallace, Paul J.;Sims, Kenneth W.;Gaetani, Glenn A.;Phillips, Erin H.
挥发物在岩浆和火山过程中发挥着重要作用。熔体包裹体是研究喷发前挥发物的有力工具，但解释它们的 H2O 和 CO2 变化可能很困难。研究了来自南极洲罗斯岛哈特角半岛、恐怖山和伯德山的 9 个巴桑岩熔体包裹体的 H2O 和 CO2 含量，以更好地了解岩浆中挥发物的行为，并深入了解岩浆运输和储存过程。对 90 个橄榄石 (Fo78–-88) 熔体包裹体以及相关块体岩石样品的成分进行了检查。熔体夹杂物中的 H2O（0·4–2·0 wt %）和 CO2（0·2–0·9 wt %，或校正蒸汽泡后的 0·2–1·8 wt %）变化不能用平衡脱气来解释。 Hut Point 样品的熔体夹杂物半径和 H2O 含量之间的强相关性表明发生了 H+ 的扩散损失。根据水汽饱和压力趋势，推断Hut Point以下约18km深度存在岩浆储层，通过对熔体包裹体H+扩散损失的模拟，表明岩浆在不到一年的时间内从该深度上升。 Terror 和 Bird 的熔体包裹体缺乏 H+ 扩散损失的证据，并且没有 CO2 通量的强化学指标。熔体包裹体的成分异质性表明发生了岩浆混合，因此很难解释 H2O 和 CO2 的趋势。来自这些火山的熔体包裹体被多重压力捕获，这与单个储存区域的捕获不一致。为了进行比较，对已发表的对罗斯岛埃里伯斯火山七个样品中 54 个橄榄石 (Fo53-83) 熔体包裹体的分析进行了重新检查。低 H2O (∼0·1 wt %) 和 CO2(0–0·2 wt %) 含量及其演化的成分表明，Erebus 岩浆在喷发前经历了浅层（<6 km）结晶，可能位于浅层储存区域。周围火山的岩浆没有显示出浅层储存的迹象。
Volatiles play an important role in magmatic and volcanic processes. Melt inclusions are a powerful tool to study pre-eruptive volatiles, but interpretation of their H2O and CO2variations can be difficult. The H2O and CO2contents of melt inclusions from nine basanites from Hut Point Peninsula, Mt Terror and Mt Bird on Ross Island, Antarctica, were studied to understand better the behavior of volatiles in the magmas and to provide insight into magma transport and storage processes. Ninety olivine-hosted (Fo78–-88) melt inclusions were examined along with the composition of the associated bulk-rock samples. The H2O (0·4–2·0 wt %) and CO2(0·2–0·9 wt %, or 0·2–1·8 wt % after correction for vapor bubbles) variations in the melt inclusions cannot be explained by equilibrium degassing. A strong correlation between melt inclusion radius and H2O content for Hut Point samples indicates that diffusive loss of H+has occurred. Based on vapor saturation pressure trends, it is inferred that a magma reservoir existed below Hut Point at a depth of ∼18 km, and by modeling diffusive loss of H+for melt inclusions, it is shown that the magmas ascended from this depth in less than a year. Melt inclusions from Terror and Bird lack evidence of diffusive loss of H+and there are no strong chemical indicators of CO2fluxing. Compositional heterogeneities in melt inclusions indicate that magma mixing occurred, making it difficult to interpret H2O and CO2trends. Melt inclusions from these volcanoes were entrapped polybarically, inconsistent with entrapment in a single storage region. Published analyses of 54 olivine-hosted (Fo53–83) melt inclusions in seven samples from Erebus volcano on Ross Island were re-examined for comparative purposes. Low H2O (∼0·1 wt %) and CO2(0–0·2 wt %) contents and the evolved compositions of these indicate that Erebus magmas undergo shallow (<6 km) crystallization before eruption, probably in a shallow storage region. Magmas from the surrounding volcanoes show no sign of shallow storage.
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影响因子：
5
作者：
Iacono-Marziano, Giada;Morizet, Yann;Gaillard, Fabrice
通讯作者：
Gaillard, Fabrice
根据橄榄石熔融包裹体的扩散失水推断的岩浆上升速率和初始水浓度
影响因子：
3.5
作者：
Yang Chen;A. Provost;P. Schiano;N. Cluzel
通讯作者：
N. Cluzel
声浪石岩浆中的表面张力和气泡成核
影响因子：
5
作者：
J. Gardner
通讯作者：
J. Gardner
包埋后结晶对蒸气饱和硅酸盐熔融包裹体的 H2O-CO2 系统影响的热力学模型
影响因子：
3.9
作者：
M. Steele‐MacInnis;Rosario Esposito;R. Bodnar
通讯作者：
R. Bodnar
影响因子：
3.9
作者：
Lesne, Priscille;Kohn, Simon C.;Behrens, Harald
通讯作者：
Behrens, Harald