Stable Vanadium Isotopes in the Igneous Rocks of the Shatsky Rise: IODP Expedition 324

沙茨基隆起火成岩中的稳定钒同位素：IODP 探险 324

• 批准号: NE/H010319/1
• 负责人: Kevin Burton
• 金额: $ 0.63万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FH010319%2F1
• 关键词: Stable; Vanadium; Isotopes; Igneous; Rocks

We live in a constantly changing world. The surface of our Earth is in perpetual motion, with hard outer surface 'plates' moving about at rates of centimeters every year. It is the movement of these plates as they pull apart and collide with one another that causes most of the Earth's earthquakes and volcanic activity. On this dynamic surface, there is a much larger area covered by sea than by land. In some places, massive amounts of volcanic rocks make isolated undersea plateaus. We call these 'Large Igneous Provinces' or 'LIPs'. Why are they there? Some people think that they might have formed when plates broke apart and let the hotter interior of the Earth melt, making lava, and cooling to form the LIPs. Other people think that LIPs are related to something coming from much deeper and hotter in the Earth. An example of this is Hawaii, where there are no plate boundaries, but lots and lots of rock. These places are sometimes called 'hotspots'. How do we test a deep hotspot origin versus shallow plate origin for LIPs? There is a LIP in the Pacific Ocean called the Shatsky Rise that is almost 150 million years old and covers an area about the size of Japan. What makes this LIP special, however, is that it sits on an old plate boundary that is no longer active. One thing that makes 'hotspot' rocks like Hawaii different from rocks formed at mid-ocean ridges where plates break apart is their chemical compositions. Therefore the Integrated Ocean Drilling Program (IODP) is going on an expedition to drill into the Shatsky volcanic rocks. The samples that we bring back can then be analyzed to help us decide whether these rocks come from deep, hot 'plumes', or if they look more like mid-ocean ridge rocks that form where plates break apart. This is an exciting expedition. We first have to drill down through over 3000 meters of water to get to the rocks below. That is the length of almost 300 football pitches lined up together. The rocks that we bring back will let us discover what was happening to cause the formation of the Shatsky LIP over 100 million years ago. Whether Shatsky resulted from a deep hot plume, or was just the result of surface plate processes will tell us a great deal about how the interior of the Earth evolves and manages its heat budget.

我们生活在一个不断变化的世界。我们的地球表面是在永恒的运动中，坚硬的外表面“板块”每年以厘米的速度移动。正是这些板块的运动，当它们彼此拉开和碰撞时，引起了地球上大多数的地震和火山活动。在这个动态表面上，海洋覆盖的面积比陆地大得多。在某些地方，大量的火山岩形成了孤立的海底高原。我们称之为“大火成岩省”或“LIPs”。他们为什么在那里？有些人认为，它们可能是在板块分裂时形成的，让地球内部更热的部分融化，形成熔岩，冷却后形成LIPs。其他人认为LIPs与来自地球更深更热的东西有关。一个例子是夏威夷，那里没有板块边界，但有很多很多的岩石。这些地方有时被称为“热点”。我们如何测试LIP的深热点起源与浅板起源？在太平洋上有一个LIP，称为Shatsky Rise，它有近1.5亿年的历史，覆盖了日本的面积。然而，这个LIP的特殊之处在于它位于一个不再活跃的旧板块边界上。像夏威夷这样的“热点”岩石与大洋中脊形成的岩石不同的一点是它们的化学成分。因此，综合大洋钻探计划（IODP）正在进行一次勘探，钻探沙特基火山岩。我们带回的样本可以进行分析，以帮助我们确定这些岩石是否来自深处，热的“羽毛”，或者它们看起来更像是板块分裂形成的洋中脊岩石。这是一次激动人心的探险。我们首先要钻过3000多米深的水才能钻到下面的岩石。这是近300个足球场的长度。我们带回的岩石将让我们发现1亿多年前造成沙茨基唇形成的原因。无论沙茨基是由一个深热的羽流造成的，还是仅仅是表面板块过程的结果，都将告诉我们很多关于地球内部如何演变和管理其热量收支的信息。

项目成果

The stable vanadium isotope composition of the mantle and mafic lavas

地幔和镁铁质熔岩的稳定钒同位素组成

• DOI: 10.1016/j.epsl.2013.01.010
• 发表时间: 2013
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Prytulak J