No depth limit to hydrovolcanic limu o Pele: analysis of limu from Lō`ihi Seamount, Hawai`i
No depth limit to hydrovolcanic limu o Pele: analysis of limu from Lō`ihi Seamount, Hawai`i
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贝利水火山 limu 无深度限制：对夏威夷 Lō`ihi 海山 limu 的分析
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
James D.L. White
中科院分区：
文献类型：
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作者：
C. Ian Schipper;James D.L. White
深海石灰是玄武岩玻璃的碎片，通常被称为“气泡墙”。当第一次发现时，它们被推断为形成于海底的火喷泉，但后来被重新解释为水火山作用的产物，当海底熔岩流捕获和蒸发海水时形成。Limu是在海水临界深度3千米以下发现的，在那里，过热的水以超临界流体而不是蒸汽的形式存在，这导致Limu o Pele形成的水火山模型被抛弃，取而代之的是岩浆二氧化碳驱动的“类似斯特姆波利亚”模型。这一修正的岩浆机制已被科学界广泛接受。本文描述了在夏威夷lhi海山东北峰顶高原地区新发现的~ 1052 mbsl富赤铁矿床。这个地点的limu集中在一个化学上单一的火山灰透镜体中，与薄的熔岩片相互作用，这些熔岩片与上覆的火山碎屑物质因不连续而分离。该矿床的几何形状和地球化学特征为其与水火山、板流有关的起源提供了强有力的证据。在这个地点，limu的异常丰富和保存使得limu的4种形态亚型——薄膜状、高原边缘状、凸膜状和贝利毛状——可以被识别出来，并与分离的破裂气泡的部分联系起来。我们将我们的讨论扩展到新的lhi矿床之外，包括对limu o Pele矿床的回顾和热力学考虑，这些考虑表明，在所有深度（包括海水临界深度以下），limu形成的水火山模型比岩浆模型更站住脚。
Deep-sea limu o Pele are shards of basaltic glass commonly described as “bubble walls.” When first identified they were inferred to form in submarine fire fountains, but were then reinterpreted as the products of hydrovolcanic volcanism, formed when submarine lava flows entrapped and vaporised seawater. Limu discovered below the c 3 km critical depth of seawater, where superheated water exists as a supercritical fluid instead of a vapour, led to the hydrovolcanic model of limu o Pele formation being discarded in favour of a magmatic CO2-driven, “strombolian-like” model. This revised magmatic mechanism has been widely accepted by the scientific community. We describe a newly discovered limu o Pele-rich deposit at ~1,052 mbsl on the northeast summit plateau region of Lō`ihi Seamount, Hawai`i. The limu at this site is concentrated in a chemically monomict ash lens interbedded with thin lava sheets that are separated from overlying volcaniclastic material by a discontinuity. The geometry and geochemistry of the deposit provide compelling evidence for a hydrovolcanic, sheet flow-related origin. The exceptional abundance and preservation of limu at this site allows 4 morphologic subtypes of limu- thin film, plateau-border, convex film, and Pele’s hair- to be identified and linked to portions of the isolated rupturing bubbles from which they are derived. We extend our discussion to beyond this new Lō`ihi deposit, by including a review of limu o Pele occurrences and thermodynamic considerations that demonstrate the hydrovolcanic model of limu formation to be more tenable than the magmatic model at all depths, including below the critical depth of seawater.
影响因子：
64.8
作者：
Sohn, Robert A.;Willis, Claire;Soule, Adam
通讯作者：
Soule, Adam