NSFGEO-NERC: Data Mining the Deep: Combining Geochemistry and Imaging Spectroscopy to Quantify Deep Hydrothermal Circulation at Mid-Ocean Ridges

NSFGEO-NERC：深海数据挖掘：结合地球化学和成像光谱学来量化大洋中脊的深部热液循环

• 批准号: NE/W007517/1
• 负责人: Damon Teagle
• 金额: $ 31.04万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW007517%2F1
• 关键词: NSFGEO; NERC; Data; Mining; Deep

Ocean crust is formed at mid-ocean ridge spreading ridges and covers more than 60% of the surface of Earth. Because of the plate tectonic cycle and subduction, the ocean crust is geologically young, on average less than 70 million years old and all is less than 200 million years; much younger than the old rocks that make up the continents. Heated seawater circulates within the ocean crust from the ridge axes until it gets consumed in subduction zones. During this circulation, these seawater-derived fluids react with the rocks forming new minerals, and key elements and molecules such as water, CO2, K, Mg are exchanged between seawater and the ocean crust. These interactions between fluids and the rock are a major - but not yet quantified - contributor to seawater chemistry, and through subduction the composition of the interior of Earth. A key challenge is that ocean drilling has not sampled the deepest ocean crust many kilometers below the seafloor. However, in the past few years, the International Continental Scientific Drilling Program's Oman Drilling Project has drilled a few kilometers of oceanic crust and the uppermost mantle in Oman, where tectonics have pushed this critical portion of Earth's crust onto the continent. In this project, scientists at Caltech will work with colleagues at the Universities of Southampton and Plymouth in the UK to investigate these drill core to work out how much exchange there has been between seawater and the deep ocean crust. We will take an innovative approach that combines detailed but traditional laboratory analyses with a novel technique, micro-imaging spectroscopy, which allows us to use the reflectance of infrared light to determine the mineralogy of the entire drill core at a spatial resolution of less than one millimeter. This research will achieve major advances in our understanding of deep circulation of fluids within the ocean crust through objective characterization at a scale and sampling completeness previously impossible. It will yield insights into the contribution of fluid-rock reactions to global geochemical cycling and seawater chemistry as well as constraining the role of deep fluid circulation in cooling and alteration of the lower oceanic crust. We will build a website with a core viewer to disseminate mineral maps of the drill cores to the broader scientific community and for educational use in classes.

海壳是在海脊中形成的，子山脉散布了山脊，覆盖了地球表面的60％以上。由于板块的构造周期和俯冲，海壳在地质上年轻，平均年龄少于7000万年，而且都少于2亿年。比构成大洲的古老岩石年轻得多。加热的海水从山脊轴上循环海皮，直到俯冲带被消耗为止。在这种循环期间，这些海水衍生的液体与形成新矿物质的岩石以及水，二氧化碳，k，mg等关键元素和分子反应，在海水和海洋地壳之间交换。流体与岩石之间的这些相互作用是主要的（但尚未量化）导致海水化学的贡献者，并通过俯冲来构成地球内部的组成。一个关键的挑战是，海洋钻井并未在海底以下几公里处采样最深的海角。然而，在过去的几年中，国际大陆科学钻探计划的阿曼钻探项目已经钻了几公里的海洋壳，而阿曼最高的地幔则在那里构造将地球上地壳的这一关键部分推向了大陆。在这个项目中，加州理工学院的科学家将与英国南安普敦和普利茅斯大学的同事合作，调查这些钻头核心，以弄清海水和深海地壳之间的交换。我们将采用一种创新的方法，该方法将详细但传统的实验室分析与新技术（微型成像光谱范围结合在一起），该方法使我们能够使用红外光的反射率以不到一毫米的空间分辨率来确定整个钻芯的矿物学。这项研究将通过以前不可能的客观表征和采样完整性来理解我们对海壳中液体深度循环的重大进展。它将洞悉流体岩石反应对全球地球化学循环和海水化学的贡献，并限制深液循环在冷却和改变下海洋壳的改变中的作用。我们将与核心观看者建立一个网站，以将钻头的矿物图传播到更广泛的科学界和课堂上的教育用途。

项目成果

Listvenite Formation During Mass Transfer into the Leading Edge of the Mantle Wedge: Initial Results from Oman Drilling Project Hole BT1B

• DOI: 10.1029/2021jb022352
• 发表时间: 2022-01
• 期刊: Journal of Geophysical Research: Solid Earth
• 作者: P. Kelemen;Juan Carlos de Obeso;J. Leong;M. Godard;K. Okazaki;A. Kotowski;C. Manning;E. Ellison;M. Menzel;J. Urai;G. Hirth;M. Rioux;D. Stockli;Romain Lafay;A. Beinlich;J. Coggon;N. Warsi;J. Matter;D. Teagle;M. Harris;K. Michibayashi;E. Takazawa;Zaher Al Sulaimani

Initial Results From the Oman Drilling Project Multi-Borehole Observatory: Petrogenesis and Ongoing Alteration of Mantle Peridotite in the Weathering Horizon

阿曼钻井项目多孔观测站的初步结果：风化层中地幔橄榄岩的岩石成因和持续蚀变

• DOI: 10.1029/2021jb022729
• 发表时间: 2021
• 期刊: Solid Earth
• 影响因子: 3.4
• 作者: Kelemen P

Geochemical Profiles Across the Listvenite-Metamorphic Transition in the Basal Megathrust of the Semail Ophiolite: Results From Drilling at OmanDP Hole BT1B

• DOI: 10.1029/2021jb022733
• 发表时间: 2021-12-01
• 期刊: JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
• 影响因子: 3.9
• 作者: Godard, M.;Carter, E. J.;Kelemen, P. B.
• 通讯作者: Kelemen, P. B.

Active near-surface mobilisation of slab-derived geochemical signatures by hyperalkaline waters in brecciated serpentinites

角砾蛇纹岩中超碱性水对板片衍生的地球化学特征的主动近地表动员

• DOI: 10.1016/j.chemgeo.2023.121822
• 发表时间: 2024
• 期刊: Chemical Geology
• 影响因子: 3.9
• 作者: Evans A

Geochemical Characterization of the Oman Crust-Mantle Transition Zone, OmanDP Holes CM1A and CM2B

阿曼壳幔过渡带、OmanDP 孔 CM1A 和 CM2B 的地球化学特征

• DOI: 10.1029/2021jb022694
• 发表时间: 2022
• 期刊: Solid Earth
• 影响因子: 3.4
• 作者: Kourim F